- Access by Xinjiang University
Inelastic light scattering from correlated electrons
Rev. Mod. Phys. 79, 175 – Published 31 January, 2007
DOI: https://doi.org/10.1103/RevModPhys.79.175
Abstract
Inelastic light scattering is an intensively used tool in the study of electronic properties of solids. Triggered by the discovery of high-temperature superconductivity in the cuprates and by new developments in instrumentation, light scattering in both the visible (Raman effect) and x-ray part of the electromagnetic spectrum has become a method complementary to optical (infrared) spectroscopy while providing additional and relevant information. The main purpose of the review is to position Raman scattering with regard to single-particle methods like angle-resolved photoemission spectroscopy, and other transport and thermodynamic measurements in correlated materials. Particular focus will be placed on photon polarizations and the role of symmetry to elucidate the dynamics of electrons in different regions of the Brillouin zone. This advantage over conventional transport (usually measuring averaged properties) provides new insights into anisotropic and complex many-body behavior of electrons in various systems. Recent developments in the theory of electronic Raman scattering in correlated systems and experimental results in paradigmatic materials such as the A15 superconductors, magnetic and paramagnetic insulators, compounds with competing orders, as well as the cuprates with high superconducting transition temperatures are reviewed. An overview of the manifestations of complexity in the Raman response due to the impact of correlations and developing competing orders is presented. In a variety of materials, observations which may be understood and a summary of important open questions that pave the way to a detailed understanding of correlated electron systems, are discussed.
Article Text
References (448)
- Abbamonte, P., G. Blumberg, A. Rusydi, A. Gozar, P. G. Evans, T. Siegrist, L. Venema, H. Eisaki, E. D. Isaacs, and G. A. Sawatzky, 2004, Nature (London) 431, 1078.
- Abrashev, M. V., C. Thomsen, and M. Surtchev, 1997, Physica C 280, 297.
- Abrikosov, A. A., 1991, Physica C 182, 191.
- Abrikosov, A. A., and L. A. Fal’kovskiĭ, 1961, Zh. Eksp. Teor. Fiz. 40, 262 [Sov. Phys. JETP 13, 179 (1961)].
- Abrikosov, A. A., and L. A. Fal’kovskiĭ, 1987, Pis'ma Zh. Eksp. Teor. Fiz. 46, 236 [JETP Lett. 46, 179 (1987)].
- Abrikosov, A. A., and L. A. Falkovsky, 1988, Physica C 156, 1.
- Abrikosov, A. A., and V. M. Genkin, 1973, Zh. Eksp. Teor. Fiz. 65, 842 [Sov. Phys. JETP 38, 417 (1974)].
- Abstreiter, G., M. Cardona, and A. Pinczuk, 1984, in Light Scattering in Solids IV, edited by M. Cardona and G. Güntherodt (Springer-Verlag, Berlin), p. 5.
- Alff, L., Y. Krockenberger, B. Welter, M. Schonecke, R. Gross, D. Manske, and M. Naito, 2003, Nature (London) 422, 698.
- Alff, L., S. Meyer, S. Kleefisch, U. Schoop, A. Marx, H. Sato, M. Naito, and R. Gross, 1999, Phys. Rev. Lett. 83, 2644.
- Allen, J. W., and J. C. Mikkelsen, 1977, Phys. Rev. B 15, 2952.
- Allen, P., 1976, Phys. Rev. B 13, 1416.
- Allen, P., and D. Rainer, 1991, Nature (London) 349, 369.
- Alloul, H., T. Ohno, and P. Mendels, 1989, Phys. Rev. Lett. 63, 1700.
- Altendorf, E., J. C. Irwin, R. Liang, and W. N. Hardy, 1992, Phys. Rev. B 45, 7551.
- Andergassen, Y., S. Caprara, C. Di Castro, and M. Grilli, 2001, Phys. Rev. Lett. 87, 056401.
- Andersen, O. K., A. I. Liechtenstein, O. Jepsen, and F. Paulsen, 1995, J. Phys. Chem. Solids 56, 1573.
- Anderson, P. W., 1958, Phys. Rev. 112, 1900.
- Anderson, P. W., 1959, J. Phys. Chem. Solids 11, 26.
- Ando, Y., A. N. Lavrov, Seiki Komiya, Kouji Segawa, and X. F. Sun, 2001, Phys. Rev. Lett. 87, 017001.
- Ando, Y., S. Komiya, K. Segawa, S. Ono, and Y. Kurita, 2004, Phys. Rev. Lett. 93, 267001.
- Ando, Y., S. Ono, X. F. Sun, J. Takeya, F. F. Balakirev, J. B. Betts, and G. S. Boebinger, 2004, Phys. Rev. Lett. 92, 247004.
- Armitage, N. P., D. H. Lu, D. L. Feng, C. Kim, A. Damascelli, K. M. Shen, F. Ronning, Z.-X. Shen, Y. Onose, Y. Taguchi, and Y. Tokura, 2001, Phys. Rev. Lett. 86, 1126.
- Ashcroft, N. W., and N. D. Mermin, 1976, Solid State Physics (Holt-Saunders, Philadelphia).
- Aslamazov, L. G., and A. I. Larkin, 1968, Sov. Phys. Solid State 10, 875.
- Axe, J. D., and G. Shirane, 1973, Phys. Rev. Lett. 30, 214.
- Balseiro, C. A., and L. M. Falicov, 1980, Phys. Rev. Lett. 45, 662.
- Bang, Y., 1993, Physica C 218, 251.
- Bardasis, A., and J. R. Schrieffer, 1961, Phys. Rev. 121, 1050.
- Basov, D. N., and T. Timusk, 2005, Rev. Mod. Phys. 77, 721.
- Bednorz, J. G., and K. A. Müller, 1986, Z. Phys. B: Condens. Matter 64, 189.
- Benfatto, L., S. Caprara, and C. Di Castro, 2000, Eur. Phys. J. B 17, 95.
- Billinge, S. J. L., M. Gutmann, and E. S. Božin, 2003, Int. J. Mod. Phys. B 17, 3640.
- Björnsson, P., M. R. Rübhausen, J. Bäckström, M. Käll, S. Eriksson, J. Eriksen, and L. Börjesson, 2000, Phys. Rev. B 61, 1193.
- Blum, F. A., 1970, Phys. Rev. B 1, 1125.
- Blumberg, G., P. Abbamonte, M. V. Klein, W. C. Lee, D. M. Ginsberg, L. L. Miller, and A. Zibold, 1996, Phys. Rev. B 53, R11930.
- Blumberg, G., M. Kang, and M. V. Klein, 1997, Phys. Rev. Lett. 78, 2461.
- Blumberg, G., M. Kang, M. V. Klein, K. Kadowaki, and C. Kendziora, 1997, Science 278, 1427.
- Blumberg, G., and M. V. Klein, 1999, J. Low Temp. Phys. 117, 1001.
- Blumberg, G., M. V. Klein, and S.-W. Cheong, 1998, Phys. Rev. Lett. 80, 564.
- Blumberg, G., A. Koitzsch, A. Gozar, B. S. Dennis, C. A. Kendziora, P. Fournier, and R. L. Greene, 2002, Phys. Rev. Lett. 88, 107002.
- Blumberg, G., A. Koitzsch, A. Gozar, B. S. Dennis, C. A. Kendziora, P. Fournier, and R. L. Greene, 2003, Phys. Rev. Lett. 90, 149702.
- Blumberg, G., R. Liu, M. V. Klein, W. C. Lee, D. M. Ginsberg, C. Gu, B. W. Veal, and B. Dabrowski, 1994, Phys. Rev. B49, 13295.
- Boebinger, G. S., Y., ando, A. Passner, T. Kimura, M. Okuya, K. Kishio, K. Tamasaku, N. Ichikawa, and S. Uchida, 1996, Phys. Rev. Lett. 77, 5417.
- Bogoliubov, N. N., V. V. Tolmachev, and D. V. Shirkov, 1959, A New Method in the Theory of Superconductivity (Bureau, New York).
- Borkowski, L. S., and P. J. Hirschfeld, 1994, Phys. Rev. B 49, 15404.
- Bozovic, I., D. Kirillov, A. Kapitulnik, K. Char, M. R. Hahn, M. R. Beasley, T. H. Geballe, Y. H. Kim, and A. J. Heeger, 1987, Phys. Rev. Lett. 59, 2219.
- Branch, D., and J. P. Carbotte, 1995, Phys. Rev. B 52, 603.
- Branch, D., and J. P. Carbotte, 1996, Phys. Rev. B 54, 13288.
- Brenig, W., and H. Monien, 1992, Solid State Commun. 83, 1009.
- Browne, D. A., and K. Levin, 1983, Phys. Rev. B 28, 4029.
- Budelmann, D., B. Schulz, M. Rübhausen, M. V. Klein, M. S. Williamsen, and P. Guptasarma, 2005, Phys. Rev. Lett. 95, 057003.
- Campuzano, J. C., M. R. Norman, and M. Randeira, 2002, in The Physics of Supreconductors Vol. II, edited by K. H. Bennemann and J. B. Ketterson (Springer-Verlag, Berlin), p. 167.
- Canali, C. M., and S. M. Girvin, 1992, Phys. Rev. B 45, 7127.
- Canfield, P. C., P. L. Gammel, and D. J. Bishop, 1998, Phys. Today 51 (10), 40.
- Caprara, S., C. Di Castro, S. Fratini, and M. Grilli, 2002, Phys. Rev. Lett. 88, 147001.
- Caprara, S., C. Di Castro, M. Grilli, and D. Suppa, 2005, Phys. Rev. Lett. 95, 117004.
- Castellani, C., C. Di Castro, and M. Grilli, 1995, Phys. Rev. Lett. 75, 4650.
- Castellani, C., C. Di Castro, and M. Grilli, 1997, Z. Phys. B: Condens. Matter 103, 137.
- Castro Neto, A. H., 2001, Phys. Rev. Lett. 86, 4382.
- Cava, R. J., R. B. van Dover, B. Batlogg, and E. A. Rietman, 1987, Phys. Rev. Lett. 58, 408.
- Cerdeira, F., T. A. Fjeldly, and M. Cardona, 1973, Phys. Rev. B 8, 4734.
- Chakravarty, S., R. B. Laughlin, D. K. Morr, and C. Nayak, 2001, Phys. Rev. B 63, 094503.
- Chandrasekhar, M., M. Cardona, and E. O. Kane, 1977, Phys. Rev. B 16, 3579.
- Chen, X. K., E. Altendorf, J. C. Irwin, R. Liang, and W. N. Hardy, 1993, Phys. Rev. B 48, 10530.
- Chen, X. K., J. C. Irwin, R. Liang, and W. N. Hardy, 1994, Physica C 227, 113.
- Chen, X. K., J. C. Irwin, H. J. Trodahl, T. Kimura, and K. Kishio, 1994, Phys. Rev. Lett. 73, 3290.
- Chen, X. K., M. J. Konstantinović, J. C. Irwin, D. D. Lawrie, and J. P. Franck, 2001, Phys. Rev. Lett. 87, 157002.
- Chesca, B., K. Ehrhardt, M. Mößle, R. Straub, D. Koelle, R. Kleiner, and A. Tsukada, 2003, Phys. Rev. Lett. 90, 057004.
- Choi, K.-Y., P. Lemmens, T. Sahaoui, G. Güntherodt, Yu. G. Pashkevich, V. P. Gnezdilov, P. Reutler, L. Pinsard-Gaudart, B. Büchner, and A. Revcolevschi, 2005, Phys. Rev. B 71, 174402.
- Chubukov, A., T. P. Devereaux, and M. V. Klein, 2006, Phys. Rev. B 73, 094512.
- Chubukov, A., D. Morr, and G. Blumberg, 1999, Solid State Commun. 112, 193.
- Chubukov, A. V., and D. M. Frenkel, 1995a, Phys. Rev. Lett. 74, 3057.
- Chubukov, A. V., and D. M. Frenkel, 1995b, Phys. Rev. B 52, 9760.
- Cooper, S. L., M. V. Klein, B. G. Pazol, J. P. Rice, and D. M. Ginsberg, 1988, Phys. Rev. B 37, 5920.
- Cooper, S. L., F. Slakey, M. V. Klein, J. P. Rice, E. D. Bukowski, and D. M. Ginsberg, 1988, Phys. Rev. B 38, 11934.
- Dagan, Y., M. M. Qazilbash, C. P. Hill, V. N. Kulkarni, and R. L. Greene, 2004, Phys. Rev. Lett. 92, 167001.
- Dagotto, E., 1999, Rep. Prog. Phys. 62, 1525.
- Dagotto, E., 2005, Science 309, 257.
- Dagotto, E., and T. M. Rice, 1996, Science 271, 618.
- Dahm, T. P., D. Manske, and B. Tewordt, 1998, Phys. Rev. B 58, 12454.
- Dahm, T. P., D. Manske, and B. Tewordt, 1999, Phys. Rev. B 59, 14740.
- Damascelli, A., Z. Hussain, and Z.-X. Shen, 2003, Rev. Mod. Phys. 75, 473.
- de Trey, P., S. Gygax, and J.-P. Jan, 1973, J. Low Temp. Phys. 11, 421.
- Deutscher, G., 1999, Nature (London) 397, 410.
- Deutscher, G., 2005, Rev. Mod. Phys. 77, 109.
- Devereaux, T. P., 1992, Phys. Rev. B 45, 12965.
- Devereaux, T. P., 1993, Phys. Rev. B 47, 5230.
- Devereaux, T. P., 1995, Phys. Rev. Lett. 74, 4313.
- Devereaux, T. P., 2003, Phys. Rev. B 68, 094503.
- Devereaux, T. P., and D. Einzel, 1995, Phys. Rev. B 51, 16336; 54, 15547(E) (1996).
- Devereaux, T. P., D. Einzel, B. Stadlober, and R. Hackl, 1994, Phys. Rev. Lett. 72, 3291.
- Devereaux, T. P., D. Einzel, B. Stadlober, R. Hackl, D. Leach, and J. J. Neumeier, 1994, Phys. Rev. Lett. 72, 396.
- Devereaux, T. P., and A. P. Kampf, 1997, Int. J. Mod. Phys. B 11, 2093.
- Devereaux, T. P., and A. P. Kampf, 1999, Phys. Rev. B 59, 6411.
- Devereaux, T. P., and A. P. Kampf, 2000, Phys. Rev. B 61, 1490.
- Devereaux, T. P., G. E. D. McCormack, and J. K. Freericks, 2003a, Phys. Rev. B 68, 075105.
- Devereaux, T. P., G. E. D. McCormack, and J. K. Freericks, 2003b, Phys. Rev. Lett. 90, 067402.
- Devereaux, T. P., A. Virosztek, and A. Zawadowski, 1996, Phys. Rev. B 54, 12523.
- Dierker, S. B., M. V. Klein, G. W. Webb, and Z. Fisk, 1983, Phys. Rev. Lett. 50, 853.
- Durst, A., and P. Lee, 2000, Phys. Rev. B 62, 1270.
- Einzel, D., and R. Hackl, 1996, J. Raman Spectrosc. 27, 307.
- Einzel, D., and D. Manske, 2004, Phys. Rev. B 70, 172507.
- Eisaki, H., N. Kaneko, D. L. Feng, A. Damascelli, P. K. Mang, K. M. Shen, Z.-X. Shen, and M. Greven, 2004, Phys. Rev. B 69, 064512.
- Elliot, R. J., and R. Loudon, 1963, Phys. Lett.3A, 189.
- Erb, A., J. Y. Genoud, F. Marti, M. Däumling, E. Walker, and R. Flükiger, 1996, J. Low Temp. Phys. 105, 1023.
- Erb, A., E. Walker, and R. Flükiger, 1996, Physica C 258, 9.
- Fabelinskiĭ, I. L., 1998, Phys. Usp. 41, 1229.
- Falikov, L. M., and J. C. Kimball, 1969, Phys. Rev. Lett. 22, 997.
- Fal’kovskiĭ, L. A., 1989, Zh. Eksp. Teor. Fiz. 95, 1145 [Sov. Phys. JETP 68, 661 (1989)].
- Fal’kovskiĭ, L. A., 1990, Usp. Fiz. Nauk 160, 71 [Sov. Phys. Usp. 33, 296 (1990)].
- Fal’kovskiĭ, L. A., 1991, Zh. Eksp. Teor. Fiz. 100, 2045 [Sov. Phys. JETP 73, 1134 (1991)].
- Falkovsky, L. A., and S. Klama, 1990, Physica C 172, 242.
- Fang, A. C., L. Capriotti, D. J. Scalapino, S. A. Kivelson, N. Kaneko, M. Greven, and A. Kapitulnik, 2006, Phys. Rev. Lett. 96, 017007.
- Fano, U., 1961, Phys. Rev. 124, 1866.
- Fleury, P., and R. Loudon, 1968, Phys. Rev. 166, 514.
- Fleury, P. A., and H. J. Guggenheim, 1970, Phys. Rev. Lett. 24, 1346.
- Fleury, P. A., S. P. S. Porto, L. E. Cheesman, and H. J. Guggenheim, 1966, Phys. Rev. Lett. 17, 84.
- Fleury, P. A., S. P. S. Porto, and R. Loudon, 1967, Phys. Rev. Lett. 18, 658.
- Forró, L., 1993, Phys. Lett. A179, 140.
- Fournier, P. K., X. Jiang, W. Jiang, S. N. Mao, T. Venkatesan, C. J. Lobb, and R. L. Greene, 1997, Phys. Rev. B 56, 14149.
- Fraas, L. M., P. F. Williams, and S. P. S. Porto, 1970, Solid State Commun. 8, 2113.
- Freericks, J. K., and T. P. Devereaux, 2001, Phys. Rev. B 64, 125110.
- Freericks, J. K., T. P. Devereaux, and R. Bulla, 2001, Phys. Rev. B 64, 233114.
- Freericks, J. K., T. P. Devereaux, R. Bulla, and Th. Pruschke, 2003, Phys. Rev. B 67, 155102.
- Freericks, J. K., T. P. Devereaux, M. Moraghebi, and S. L. Cooper, 2005, Phys. Rev. Lett. 94, 216401.
- Freericks, J. K., and P. Miller, 2000, Phys. Rev. B 62, 10022.
- Freericks, J. K., and V. Zlatić, 2003, Rev. Mod. Phys. 75, 1333.
- Freitas, P. J., and R. R. P. Singh, 2000, Phys. Rev. B 62, 5525.
- Fujita, M., K. Yamada, H. Hiraka, P. M. Gehring, S. H. Lee, S. Wakimoto, and G. Shirane, 2002, Phys. Rev. B 65, 064505.
- Fulde, P., 1995, Electronic Correlations in Solid and Molecules (Springer-Verlag, Berlin).
- Fulde, P., and S. Strassler, 1965, Phys. Rev. 140, A519.
- Gallais, Y., A. Sacuto, P. Bourges, Y. Sidis, A. Forget, and D. Colson, 2002, Phys. Rev. Lett. 88, 177401.
- Gallais, Y., A. Sacuto, and D. Colson, 2004, Physica C 408, 785.
- Gallais, Y., A. Sacuto, T. P. Devereaux, and D. Colson, 2005, Phys. Rev. B 71, 012506.
- Gasparov, L. V., P. Lemmens, M. Brinkmann, N. N. Kolesnikov, and G. Güntherodt, 1997, Phys. Rev. B 55, 1223.
- Gasparov, L. V., P. Lemmens, N. N. Kolesnikov, and G. Güntherodt, 1998, Phys. Rev. B 58, 11753.
- Gebhard, F., 1997, The Mott Metal-Insulator Transition (Springer-Verlag, Berlin).
- Geerk, J., H. Rietschel, and U. Schneider, 1984, Phys. Rev. B 30, 459.
- Ginzburg, V. L., 1998, Vestn. Ross. Akad. Nauk 68, 51, and private communication.
- Goncharov, A. F., and V. V. Struzhkin, 2003, J. Raman Spectrosc. 34, 532.
- Götze, W., and P. Wölfle, 1972, Phys. Rev. B 6, 1226.
- Gozar, A., and G. Blumberg, 2005, in Frontiers in Magnetic Materials, edited by A. V. Narlikar (Springer-Verlag, Berlin), p. 653.
- Gozar, A., G. Blumberg, B. S. Dennis, B. S. Shastry, N. Motoyama, H. Eisaki, and S. Uchida, 2001, Phys. Rev. Lett. 87, 197202.
- Gozar, A., G. Blumberg, P. B. Littlewood, B. S. Dennis, N. Motoyama, H. Eisaki, and S. Uchida, 2003, Phys. Rev. Lett. 91, 087401.
- Gozar, A., B. S. Dennis, G. Blumberg, S. Komiya, and Y. Ando, 2004, Phys. Rev. Lett. 93, 027001.
- Gozar, A., S. Komiya, Y. Ando, and G. Blumberg, 2005, in Frontiers in Magnetic Materials, edited by A. V. Narlikar (Springer-Verlag, Berlin), p. 755.
- Greytak, T. J., and J. Yan, 1969, Phys. Rev. Lett. 22, 987.
- Grüninger, M., R. Rückamp, M. Windt, P. Reutler, C. Zobel, T. Lorenz, A. Freimuth, and A. Revcolevschi, 2002, Nature (London) 418, 39.
- Gurtubay, I. G., Wei Ku, J. M. Pitarke, A. G. Eguiluz, B. C. Larson, J. Tischler, and P. Zschack, 2004, Phys. Rev. B 70, 201201.
- Hackl, R., W. Gläser, P. Müller, D. Einzel, and K. andres, 1988, Phys. Rev. B 38, 7133.
- Hackl, R., and R. Kaiser, 1988, J. Phys. C 21, L453.
- Hackl, R., R. Kaiser, and S. Schicktanz, 1982, in Superconductivity in - and -band Metals IV, edited by W. Buckel and W. Weber (Kernforschungzentrum, Karlsruhe), p. 559.
- Hackl, R., R. Kaiser, and S. Schicktanz, 1983, J. Phys. C 16, 1729.
- Hackl, R., P. Müller, D. Einzel, and W. Gläser, 1989, Physica C 162-164, 1241.
- Hackl, R., M. Opel, P. F. Müller, G. Krug, B. Stadlober, R. Nemetschek, H. Berger, and L. Forró, 1996, J. Low Temp. Phys. 105, 733.
- Hackl, R., L. Tassini, F. Venturini, Ch. Hartinger, A. Erb, N. Kikugawa, and T. Fujita, 2005, in Advances in Solid State Physics, edited by B. Kramer (Springer-Verlag, Berlin), Vol. 45, p. 225.
- Hadjiev, V. G., X. Zhou, T. Strohm, M. Cardona, Q. M. Lin, and C. W. Chu, 1998, Phys. Rev. B 58, 1043.
- Halley, J. W., 1978, Phys. Rev. Lett. 41, 1605.
- Hanaguri, T., C. Lupien, Y. Kohsaka, D.-H. Lee, M. Azuma, M. Takano, H. Takagi, and J. C. Davis, 2004, Nature (London) 430, 1001.
- Hanamura, E., N. T. Dan, and Y. Tanabe, 2000, Phys. Rev. B 62, 7033.
- Hardy, W. N., D. A. Bonn, D. C. Morgan, R. Liang, and K. Zhang, 1993, Phys. Rev. Lett. 70, 3999.
- Hartschuh, A., E. J. Sanchez, X. S. Xie, and L. Novotny, 2003, Phys. Rev. Lett. 90, 095503.
- Hayes, W., and R. Loudon, 2005, Scattering of Light by Crystals (Dover, New York).
- Hewitt, K. C., and J. C. Irwin, 2002, Phys. Rev. B 66, 054516.
- Hewitt, K. C., N. L. Wang, J. C. Irwin, D. M. Pooke, A. E. Pantoja, and H. J. Trodahl, 1999, Phys. Rev. B 60, R9943.
- Heyen, E. T., R. Liu, M. Cardona, S. Piñol, R. J. Melville, E. Morán, and M. A. Alario-Franco, 1991, Phys. Rev. B 43, 2857.
- Hinkov, V., S. Pailhès, P. Bourges, A. Ivanov, A. Kulakov, C. T. Lin, D. P. Chen, C. Bernhard, and B. Keimer, 2004, Nature (London) 430, 650.
- Ho, C. M., V. N. Muthukumar, M. Ogata, and P. W. Anderson, 2001, Phys. Rev. Lett. 86, 1626.
- Hoffmann, A., P. Lemmens, G. Güntherodt, V. Thomas, and K. Winzer, 1994, Physica C 235-240, 1897.
- Hoffman, J. E., K. McElroy, D.-H. Lee, K. M. Lang, H. Eisaki, S. Uchida, and J. C. Davis, 2002, Science 297, 1148.
- Hoffstein, V., and R. W. Cohen, 1969, Phys. Lett. 29A, 603.
- Homes, C. C., P. B. Clayman, J. L. Peng, and R. L. Greene, 1997, Phys. Rev. B 56, 5525.
- Homes, C. C., S. V. Dordevic, M. Strongin, D. A. Bonn, R. Liang, W. N. Hardy, S. Komiya, Y. Ando, G. Yu, N. Kaneko, X. Zhao, M. Greven, D. N. Basov, and T. Timusk, 2004, Nature (London) 430, 539.
- Howald, C., H. Eisaki, N. Kaneko, M. Greven, and A. Kapitulnik, 2003, Phys. Rev. B 67, 014533.
- Huntley, D. J., and R. F. Frindt, 1974, Can. J. Phys. 52, 861.
- Imada, M., A. Fujimori, and Y. Tokura, 1998, Rev. Mod. Phys. 70, 1039.
- Ipatova, I. P., M. I. Kaganov, and A. V. Subashiev, 1983, Zh. Eksp. Teor. Fiz. 84, 1830 [Sov. Phys. JETP 57, 1066 (1983)].
- Ipatova, I. P., A. V. Subashiev, and V. A. Voitenko, 1981, Solid State Commun. 37, 893.
- Itai, K., 1992, Phys. Rev. B 45, 707.
- Jain, J. K., and S. Das Sarma, 1987, Phys. Rev. B 36, 5949.
- Jandl, S., M. Iliev, C. Thomsen, T. Ruf, M. Cardona, B. M. Wanklyn, and C. Chen, 1993, Solid State Commun. 87, 609.
- Jánossy, A., T. Fehér, and A. Erb, 2003, Phys. Rev. Lett. 91, 177001.
- Jiang, C., and J. P. Carbotte, 1996, Phys. Rev. B 53, 11868.
- Junod, A., T. Jarlborg, and J. Muller, 1983, Phys. Rev. B 27, 1568.
- Jurecka, C., V. Grützun, A. Friedrich, and W. Brenig, 2001, Eur. Phys. J. B 21, 469.
- Kaiser, D. L., F. Holtzberg, B. A. Scott, and T. R. McGuire, 1987, Appl. Phys. Lett. 51, 1040.
- Kampf, A. P., and W. Brenig, 1992, Z. Phys. B: Condens. Matter 89, 313.
- Kang, M., G. Blumberg, M. V. Klein, and N. N. Kolesnikov, 1996, Phys. Rev. Lett. 77, 4434.
- Kang, M., G. Blumberg, M. V. Klein, and N. N. Kolesnikov, 1997, Phys. Rev. B 56, R11427.
- Katanin, A. A., and A. P. Kampf, 2003, Phys. Rev. B 67, 100404.
- Katsufuji, T., Y. Tokura, T. Ido, and S. Uchida, 1994, Phys. Rev. B 48, 16131.
- Kee, H.-Y., K. Maki, and C. H. Chung, 2003, Phys. Rev. B 67, 180504.
- Kendziora, C., M. C. Martin, J. Hartge, and L. Mihály, 1993, Phys. Rev. B 48, 3531.
- Kendziora, C., and A. Rosenberg, 1995, Phys. Rev. B 52, R9867.
- Khaĭkin, M. S., and V. P. Bykov, 1956, Sov. Phys. JETP 30, 191 [ 3, 119 (1956)].
- Khveshchenko, D. V., and P. B. Wiegmann, 1994, Phys. Rev. Lett. 73, 500.
- Kim, T. K., A. A. Kordyuk, S. V. Borisenko, A. Koitzsch, M. Knupfer, H. Berger, and J. Fink, 2003, Phys. Rev. Lett. 91, 167002.
- Kirillov, D., J. P. Collman, J. T. McDevitt, G. T. Yee, M. J. Holcomb, and I. Bozovic, 1988, Phys. Rev. B 37, 3660.
- Kivelson, S. A., I. P. Bindloss, E. Fradkin, V. Oganesyan, J. M. Tranquada, A. Kapitulnik, and C. Howald, 2003, Rev. Mod. Phys. 75, 1201.
- Kivelson, S. A., E. Fradkin, and V. J. Emery, 1998, Nature (London) 393, 550.
- Klauss, H.-H., W. Wagener, M. Hillberg, W. Kopmann, H. Walf, F. J. Litterst, M. Hücker, and B. Büchner, 2000, Phys. Rev. Lett. 85, 4590.
- Klein, B. M., L. L. Boyer, D. A. Papaconstantopoulos, and L. F. Mattheiss, 1978, Phys. Rev. B 18, 6411.
- Klein, M. V., 1982a, in Superconductivity in - and -band Metals IV, edited by W. Buckel and W. Weber (Kernforschungzentrum, Karlsruhe), p. 539.
- Klein, M. V., 1982b, in Light Scattering in Solids III, edited by M. Cardona and G. Güntherodt (Springer-Verlag, Berlin), p. 121.
- Klein, M. V., 1982c, Phys. Rev. B 25, 7192.
- Klein, M. V., 1983, in Light Scattering in Solids I, edited by M. Cardona and G. Güntherodt (Springer-Verlag, Berlin), p. 147.
- Klein, M. V., S. L. Cooper, A. L. Kotz, Ran Liu, D. Reznik, F. Slakey, W. C. Lee, and D. M. Ginsberg, 1991, Physica C 185, 72.
- Klein, M. V., and S. B. Dierker, 1984, Phys. Rev. B 29, 4976.
- Knoll, P., M. Mayer, W. Brenig, and Ch. Waidacher, 1996, J. Low Temp. Phys. 105, 383.
- Knoll, P., C. Thomsen, M. Cardona, and P. Murugaraj, 1990, Phys. Rev. B 42, 4842.
- Koitzsch, A., G. Blumberg, A. Gozar, B. S. Dennis, P. Fournier, and R. L. Greene, 2003, Phys. Rev. B 67, 184522.
- Kokales, J. D., P. Fournier, L. V. Mercaldo, V. V. Talanov, C. A. Kendziora, R. L. Greene, and S. M. Anlage, 2000, Phys. Rev. Lett. 85, 3696.
- Kostur, V. N., 1992, Z. Phys. B: Condens. Matter 89, 149.
- Kostur, V. N., and G. M. Eliashberg, 1991, Pis'ma Zh. Eksp. Teor. Fiz. 53, 373 Kostur, V. N., and G. M. Éliashberg,[JETP Lett. 53, 391 (1991)].
- Kosztin, J., and A. Zawadowski, 1991, Solid State Commun. 78, 1029.
- Kotani, A., and S. Shin, 2001, Rev. Mod. Phys. 73, 203.
- Kramer, B., and M. Sassetti, 2000, Phys. Rev. B 62, 4238.
- Kramers, H. A., and W. Heisenberg, 1925, Z. Phys. 31, 681.
- Krantz, M. C., and M. Cardona, 1994, Phys. Rev. Lett. 72, 3290.
- Krüger, R., B. Schulz, S. Naler, R. Rauer, D. Budelmann, J. Bäckström, K. H. Kim, S.-W. Cheong, V. Perebeinos, and M. Rübhausen, 2004, Phys. Rev. Lett. 92, 097203.
- Ku, W., W. E. Pickett, R. T. Scalettar, and A. G. Equiluz, 2002, Phys. Rev. Lett. 88, 057001.
- Landau, L. D., and E. M. Lifshitz, 1960, Electrodynamics of Continuous Media (Pergamon, Oxford), p. 377.
- Landsberg, G. S., and L. I. Mandelstam, 1928, Naturwiss. 16, 557.
- Lee, H. C., and H.-Y. Choi, 2002, Phys. Rev. B 65, 174530.
- Lei, X. L., C. S. Ting, and J. L. Birman, 1985, Phys. Rev. B 32, 1464.
- Lemmens, P., G. Güntherodt, and C. Gros, 2003, Phys. Rep. 375, 1.
- Le Tacon, M., A. Sacuto, and D. Colson, 2005, Phys. Rev. B 71, 100504.
- Liang, R., D. A. Bonn, and W. N. Hardy, 2000, Physica C 336, 57.
- Liang, R., D. A. Bonn, W. N. Hardy, J. C. Wynn, K. A. Moler, L. Lu, S. Larochelle, L. Zhou, M. Greven, L. Lurio, and S. G. J. Mochrie, 2002, Physica C 383, 1.
- Limonov, M., S. Lee, S. Tajima, and A. Yamanaka, 2002, Phys. Rev. B 66, 054509.
- Limonov, M., A. I. Rykov, S. Tajima, and A. Yamanaka, 1998, Phys. Rev. Lett. 80, 825.
- Limonov, M., D. Shantsev, S. Tajima, and A. Yamanaka, 2002, Phys. Rev. B 65, 024515.
- Limonov, M., S. Tajima, and A. Yamanaka, 2000, Phys. Rev. B 62, 11859.
- Lindroos, M., S. Sahrakorpi, and A. Bansil, 2002, Phys. Rev. B 65, 054514.
- Littlewood, P. B., 1987, Phys. Rev. B 36, 3108.
- Littlewood, P. B., and C. M. Varma, 1981, Phys. Rev. Lett. 47, 811.
- Littlewood, P. B., and C. M. Varma, 1982, Phys. Rev. B 26, 4883.
- Liu, C. S., H. G. Luo, W. C. Wu, and T. Xiang, 2006, Phys. Rev. B 73, 174517.
- Liu, H. L., G. Blumberg, M. V. Klein, P. Guptasarma, and D. G. Hinks, 1999, Phys. Rev. Lett. 82, 3524.
- Liu, R., D. Salamon, M. V. Klein, S. L. Cooper, W. C. Lee, S.-W. Cheong, and D. M. Ginsberg, 1993, Phys. Rev. Lett. 71, 3709.
- Lorenzana, J., and G. A. Sawatzky, 1995, Phys. Rev. B 52, 9576.
- Löwdin, P.-O., 1951, J. Chem. Phys. 19, 1396.
- Lyons, K. B., P. A. Fleury, J. P. Remeika, A. S. Cooper, and T. J. Negran, 1988, Phys. Rev. B 37, 2353.
- Lyons, K. B., S. H. Liou, M. Hong, H. S. Chen, J. Kwo, and T. J. Negran, 1987, Phys. Rev. B 36, 5592.
- Lyons, K. B., P. E. Sulewski, P. A. Fleury, H. L. Carter, A. S. Cooper, G. P. Espinoza, Z. Fisk, and S.-W. Cheong, 1989, Phys. Rev. B 39, 9693.
- Machida, K., 1989, Physica C 87, 192.
- Mahan, G. D., 2000, Many-Particle Physics (Kluwer Academic, New York).
- Maki, K., and T. Tsuneto, 1962, Prog. Theor. Phys. 28, 163.
- Maksimov, A. A., I. I. Tartakovskiĭ, V. B. Timofeev, and L. A. Fal’kovskiĭ, 1990, Zh. Eksp. Teor. Fiz.97, 1047 [Sov. Phys. JETP 70, 588 (1990)].
- Mandrus, D., L. Forró, D. Koller, and L. Mihály, 1991, Nature (London) 351, 460.
- Mannella, N., A. Rosenhahn, C. H. Booth, S. Marchesini, B. S. Mun, S.-H. Yang, K. Ibrahim, Y. Tomioka, and C. S. Fadeley, 2004, Phys. Rev. Lett. 92, 166401.
- Mannella, N., W. L. Yang, X. J. Zhou, H. Zheng, J. F. Mitchell, J. Zaanen, T. P. Devereaux, N. Nagaosa, Z. Hussain, and Z.-X. Shen, 2005, Nature (London) 438, 474.
- Manske, D., A. Bock, C. T. Rieck, and D. Fay, 1998, Phys. Rev. B 58, 8841.
- Manske, D., C. T. Rieck, R. Das Sharma, A. Bock, and D. Fay, 1997, Phys. Rev. B 56, R2940.
- Martinho, H., A. A. Martin, C. Rettori, and C. T. Lin, 2004, Phys. Rev. B 69, 180501.
- Masui, T., M. Limonov, H. Uchiyama, S. Lee, S. Tajima, and A. Yamanaka, 2003, Phys. Rev. B 68, 060506.
- Masui, T., M. Limonov, H. Uchiyama, S. Tajima, and A. Yamanaka, 2005, Phys. Rev. Lett. 95, 207001.
- Matsui, H., K. Terashima, T. Sato, T. Takahashi, M. Fujita, and K. Yamada, 2005, Phys. Rev. Lett. 95, 017003.
- Mattheiss, L. F., and W. Weber, 1982, Phys. Rev. B 25, 2248.
- Mattis, D. C., and J. Bardeen, 1958, Phys. Rev. 111, 412.
- McElroy, K., H. Eisaki, S. Uchida, and J. C. Davis, 2005, Science 309, 1048.
- McElroy, K., R. W. Simmonds, J. E. Hoffman, D.-H. Lee, J. Orenstein, H. Eisaki, S. Uchida, and J. C. Davis, 2003, Nature (London) 422, 592.
- Metzner, W., D. Rohe, and S. Andergassen, 2003, Phys. Rev. Lett. 91, 066402.
- Migdal, A. B., 1958, Sov. Phys. JETP 7, 996.
- Mills, D. L., A. A. Maradudin, and E. Burstein, 1970, Ann. Phys. (N.Y.) 56, 504.
- Mishchenko, E. G., 1999, Phys. Rev. B 59, 14892.
- Misochko, O. V., K. Sakai, S. Nakashima, and G. Gu, 1999, Phys. Rev. B 60, 1326.
- Moler, K. A., D. J. Baar, J. S. Urbach, Ruixing Liang, W. N. Hardy, and A. Kapitulnik, 1994, Phys. Rev. Lett. 73, 2744.
- Monien, H., and A. Zawadowski, 1989, Phys. Rev. Lett. 63, 911.
- Monien, H., and A. Zawadowski, 1990, Phys. Rev. B 41, 8798.
- Monthoux, P., and D. J. Scalapino, 1994, Phys. Rev. Lett. 72, 1874.
- Mooradian, A., and G. B. Wright, 1966, Phys. Rev. Lett. 16, 999.
- Moore, D. F., R. B. Zubeck, J. M. Rowell, and M. R. Beasley, 1979, Phys. Rev. B 20, 2721.
- Morita, S., S. Imai, S. Yamashita, N. Mikoshiba, N. Toyota, T. Fukase, and T. Nakanomyo, 1984, Physica B & C 126, 601.
- Morr, D. K., and A. V. Chubukov, 1997, Phys. Rev. B 56, 9134.
- Morr, D. K., A. V. Chubukov, A. P. Kampf, and G. Blumberg, 1996, Phys. Rev. B 54, 3468.
- Munzar, D., and M. Cardona, 2003, Phys. Rev. Lett. 90, 077001.
- Naeini, J. G., X. K. Chen, J. C. Irwin, M. Okuya, T. Kimura, and K. Kishio, 1999, Phys. Rev. B 59, 9642.
- Naito, M., and M. Hepp, 2000, Jpn. J. Appl. Phys., Part 2 39, L485.
- Nagamatsu, J., N. Nakagawa, T. Muranaka, Y. Zenitani, and J. Akimitsu, 2001, Nature (London) 410, 63.
- Nakamae, S., K. Behnia, N. Mangkorntong, M. Nohara, H. Takagi, S. J. C. Yates, and N. E. Hussey, 2003, Phys. Rev. B 68, 100502(R).
- Nambu, Y., 1960, Phys. Rev. 117, 648.
- Nemetschek, R., R. Hackl, M. Opel, R. Philipp, M. T. Beal-Monod, J. B. Bieri, K. Maki, A. Erb, and E. Walker, 1998, Eur. Phys. J. B 5, 495.
- Nemetschek, R., O. V. Misochko, B. Stadlober, and R. Hackl, 1993, Phys. Rev. B 47, 3450.
- Nemetschek, R., M. Opel, C. Hoffmann, P. F. Müller, R. Hackl, H. Berger, L. Forró, A. Erb, and E. Walker, 1997, Phys. Rev. Lett. 78, 4837.
- Nakamae, S., K. Behnia, N. Mangkorntong, M. Nohara, H. Takagi, S. J. C. Yates, and N. E. Hussey, 2003, Phys. Rev. B 68, 100502(R).
- Nyhus, P., S. L. Cooper, and Z. Fisk, 1995, Phys. Rev. B 51, 15626.
- Nyhus, P., S. L. Cooper, Z. Fisk, and J. Sarrao, 1995, Phys. Rev. B 52, 14308.
- Nyhus, P., S. L. Cooper, Z. Fisk, and J. Sarrao, 1997, Phys. Rev. B 55, 12488.
- Nyhus, P., S. Yoon, M. Kauffman, S. L. Cooper, Z. Fisk, and J. Sarrao, 1997, Phys. Rev. B 56, 2717.
- Okamoto, S., S. Ishihara, and S. Maekawa, 2002, Phys. Rev. B 66, 014435.
- Onose, Y., Y. Taguchi, T. Ishikawa, S. Shinomori, K. Ishizaka, and Y. Tokura, 1999, Phys. Rev. Lett. 82, 5120.
- Onose, Y., Y. Taguchi, K. Ishizaka, and Y. Tokura, 2001, Phys. Rev. Lett. 87, 217001.
- Onose, Y., Y. Taguchi, K. Ishizaka, and Y. Tokura, 2004, Phys. Rev. B 69, 024504.
- Opel, M., R. Nemetschek, C. Hoffmann, R. Philipp, P. F. Müller, R. Hackl, I. Tüttő, A. Erb, B. Revaz, E. Walker, H. Berger, and L. Forró, 2000, Phys. Rev. B 61, 9752.
- Panagopoulos, C., and T. Xiang, 1998, Phys. Rev. Lett. 81, 2336.
- Parkinson, J. B., 1969, J. Phys. C 2, 2012.
- Pashkevich, Yu. G., V. A. Blinkin, V. P. Gnezdilov, V. V. Tsapenko, V. V. Eremenko, P. Lemmens, M. Fischer, M. Grove, G. Güntherodt, L. Degiorgi, P. Wachter, J. M. Tranquada, and D. J. Buttrey, 2000, Phys. Rev. Lett. 84, 3919.
- Pekker, S., A. Jánossy, and A. Rockenbauer, 1991, Physica C 181, 11.
- Perali, A., C. Castellani, C. Di Castro, and M. Grilli, 1996, Phys. Rev. B 54, 16216.
- Perebeinos, V., and P. B. Allen, 2001, Phys. Rev. B 64, 085118.
- Perkovitz, S., M. Merlin, and L. R. Testardi, 1976, Solid State Commun. 18, 1059.
- Pinczuk, A., and G. Abstreiter, 1989, in Light Scattering in Solids V, edited by M. Cardona and G. Güntherodt (Springer-Verlag, Berlin), p. 153.
- Pines, D., 1963, Elementary Excitations in Solids (Benjamin, New York).
- Pines, D., and P. Nozières, 1966, The Theory of Quantum Liquids: Normal Fermi Liquids (Addison-Wesley, New York).
- Placzek, G., 1934, Marx’s Handbuch der Radiologie (Akademische Verlagsanstalt Leipzig, 209), Vol. 6.
- Platzman, P. M., 1965, Phys. Rev. 139, A379.
- Platzman, P. M., and E. D. Isaacs, 1998, Phys. Rev. B 57, 11107.
- Platzman, P. M., and N. Tzoar, 1964, Phys. Rev. 136, A11.
- Pleijel, H., 1930, Presentation Speech of the Nobel Prize in Physics (http://nobelprize.org/nobel_prizes/physics/laureates/1930/press.html).
- Prelovšek, P., and J. Jaklič, 1996, Phys. Rev. B 53, 15095.
- Pruschke, T., M. Jarrell, and J. K. Freericks, 1995, Adv. Phys. 44, 187.
- Qazilbash, M. M., A. Koitzsch, B. S. Dennis, A. Gozar, Hamza Balci, C. A. Kendziora, R. L. Greene, and G. Blumberg, 2005, Phys. Rev. B 72, 214510.
- Quilty, J. W., S. Lee, S. Tajima, and A. Yamanaka, 2003, Phys. Rev. Lett. 90, 207006.
- Quilty, J. W., S. Lee, A. Yamamoto, and S. Tajima, 2002, Phys. Rev. Lett. 88, 087001.
- Quilty, J. W., H. J. Trodahl, and D. M. Pooke, 1998, Phys. Rev. B 57, R11097.
- Radaelli, P. G., J. D. Jorgensen, A. J. Schultz, J. L. Peng, and R. J. Green, 1994, Phys. Rev. B 49, 15322.
- Raman, C. V., and K. S. Krishnan, 1928, Nature (London) 121, 501.
- Rashkeev, S. N., and G. Wendin, 1993, Phys. Rev. B 47, 11603.
- Renner, Ch., and Ø. Fischer, 1995, Phys. Rev. B 51, 9208.
- Reznik, D., S. L. Cooper, M. V. Klein, W. C. Lee, D. M. Ginsberg, A. A. Maksimov, A. V. Puchkov, I. I. Tartakovskii, S.-W. Cheong, and 1993, Phys. Rev. B 48, 7624.
- Rho, H., S. L. Cooper, S. Nakatsuji, H. Fukazawa, and Y. Maeno, 2003, Phys. Rev. B 68, 100404.
- Rho, H., C. S. Snow, S. L. Cooper, Z. Fisk, A. Comment, and J.-P. Ansermet, 2002, Phys. Rev. Lett. 88, 127401.
- Richards, D., 2000, Phys. Rev. B 61, 7517.
- Romero, D. B., Y. Moritomo, N. Dieckmann, J. F. Mitchell, and H. D. Drew, 2001, Phys. Rev. B 63, 132404.
- Roulin, M., A. Junod, A. Erb, and E. Walker, 2002, Phys. Rev. Lett. 80, 1722.
- Rübhausen, M., O. A. Hammerstein, A. Bock, U. Merkt, C. T. Rieck, P. Guptasarma, D. G. Hinks, and M. V. Klein, 1999, Phys. Rev. Lett. 82, 5349.
- Rübhausen, M., C. T. Rieck, N. Dieckmann, K. O. Subke, A. Bock, and U. Merkt, 1997, Phys. Rev. B 56, 14797.
- Rudman, D. A., and M. R. Beasley, 1984, Phys. Rev. B 30, 2590.
- Sachdev, S., 1999, Quantum Phase Transitions (Cambridge University Press, Cambridge, England).
- Sacuto, A., J. Cayssol, P. Monod, and D. Colson, 2000, Phys. Rev. B 61, 7122.
- Sacuto, A., R. Combescot, N. Bontemps, C. A. Müller, V. Viallet, and D. Colson, 1998, Phys. Rev. B 58, 11721.
- Saitoh, E., S. Okamoto, K. T. Takahashi, K. Tobe, K. Yamamoto, T. Kimura, S. Ishihara, S. Maekawa, and Y. Tokura, 2001, Nature (London) 410, 180.
- Sandvik, A., S. Capponi, D. Poilblanc, and E. Dagotto, 1998, Phys. Rev. B 57, 8478.
- Sassetti, M., and B. Kramer, 1998, Phys. Rev. Lett. 80, 1485.
- Sassetti, M., F. Napoli, and B. Kramer, 1999, Phys. Rev. B 59, 7297.
- Scalapino, D. J., 1995, Phys. Rep. 250, 330.
- Schicktanz, S., R. Kaiser, E. Schneider, and W. Gläser, 1980, Phys. Rev. B 22, 2386.
- Schicktanz, S., R. Kaiser, W. Weber, C. Politis, R. Flükiger, and P. Bujard, 1982, Phys. Rev. B 26, 4909, and references therein.
- Schneemeyer, L. F., J. V. Waszczak, T. Siegrist, R. B. van Dover, L. W. Rupp, B. Batlogg, R. J. Cava, and D. W. Murphy, 1987, Nature (London) 328, 601.
- Schulz, B., J. Bäckström, D. Budelmann, R. Maeser, M. Rübhausen, M. V. Klein, E. Schoeffel, A. Mihill, and S. Yoon, 2005, Rev. Sci. Instrum. 76, 073107.
- Shastry, B. S., and B. I. Shraiman, 1990, Phys. Rev. Lett. 65, 1068.
- Shastry, B. S., and B. I. Shraiman, 1991, Int. J. Mod. Phys. B 5, 365.
- Shen, Z.-X., D. S. Dessau, B. O. Wells, D. M. King, W. E. Spicer, A. J. Arko, D. Marshall, L. W. Lombardo, A. Kapitulnik, P. Dickinson, S. Doniach, and J. DiCarlo, 1993, Phys. Rev. Lett. 70, 1553.
- Sherman, E. Ya., C. Ambrosch-Draxl, and O. V. Misochko, 2002, Phys. Rev. B 65, 140510.
- Sherman, E. Ya., O. V. Misochko, and P. Lemmens, 2003, in Spectra of High Superconductors: A Theoretical View, edited by N. M. Plakida (Taylor & Francis, London).
- Shvaika, A. M., 2000, Physica C 341-348, 177.
- Shvaika, A. M., O. Vorobyov, J. K. Freericks, and T. P. Devereaux, 2004, Phys. Rev. Lett. 93, 137402.
- Shvaika, A. M., O. Vorobyov, J. K. Freericks, and T. P. Devereaux, 2005, Phys. Rev. B 71, 045120.
- Sidis, Y., S. Pailhès, B. Keimer, P. Bourges, C. Ulrich, and L. P. Regnault, 2004, Phys. Status Solidi B 241, 1204.
- Sigrist, M., T. M. Rice, and F. C. Zhang, 1994, Phys. Rev. B 49, 12058.
- Silva Neto, M. B., and L. Benfatto, 2005, Phys. Rev. B 72, 140401.
- Singh, R. R. P., P. A. Fleury, K. B. Lyons, and P. E. Sulewski, 1989, Phys. Rev. Lett. 62, 2736.
- Singley, E. J., D. N. Basov, K. Kurahashi, T. Uefuji, and K. Yamada, 2001, Phys. Rev. B 64, 224503.
- Skinta, J. A., M. S. Kim, T. Lemberger, T. Greibe, and M. Naito, 2002, Phys. Rev. Lett. 88, 207005.
- Skinta, J. A., T. Lemberger, T. Greibe, and M. Naito, 2002, Phys. Rev. Lett. 88, 207003.
- Slakey, F., M. V. Klein, E. D. Bukowski, and D. M. Ginsberg, 1990, Phys. Rev. B 41, 2109.
- Slakey, F., M. V. Klein, J. P. Rice, and D. M. Ginsberg, 1990, Phys. Rev. B 42, 2643.
- Slakey, F., M. V. Klein, J. P. Rice, and D. M. Ginsberg, 1991, Phys. Rev. B 43, 3764.
- Smekal, A., 1923, Naturwiss. 11, 873.
- Snow, C. S., S. L. Cooper, G. Cao, J. E. Crow, H. Fukazawa, S. Nakatsuji, and Y. Maeno, 2002, Phys. Rev. Lett. 89, 226401.
- Snow, C. S., S. L. Cooper, D. P. Young, Z. Fisk, A. Comment, and J.-P. Ansermet, 2001, Phys. Rev. B 64, 174412.
- Snow, C. S., J. F. Karpus, S. L. Cooper, T. E. Kidd, and T.-C. Chiang, 2003, Phys. Rev. Lett. 91, 136402.
- Sooryakumar, F., and M. V. Klein, 1980, Phys. Rev. Lett. 45, 660.
- Sooryakumar, F., and M. V. Klein, 1981, Phys. Rev. B 23, 3213.
- Sooryakumar, F., M. V. Klein, and R. F. Frindt, 1981, Phys. Rev. B 23, 3222.
- Stadlober, B., G. Krug, R. Nemetschek, R. Hackl, J. L. Cobb, and J. T. Markert, 1995, Phys. Rev. Lett. 74, 4911.
- Stadlober, B., R. Nemetschek, O. V. Misochko, R. Hackl, P. Müller, J. J. Neumeier, and K. Winzer, 1994, Physica B 194-196, 1539.
- Staufer, T., R. Hackl, and P. Müller, 1990, Solid State Commun. 75, 975.
- Staufer, T., R. Nemetschek, R. Hackl, P. Müller, and H. Veith, 1992, Phys. Rev. Lett. 68, 1069.
- Stock, C., W. J. L. Buyers, Z. Yamani, C. L. Broholm, J.-H. Chung, Z. Tun, R. Liang, D. Bonn, W. N. Hardy, and R. J. Birgeneau, 2006, Phys. Rev. B 73, 100504.
- Strohm, T., and M. Cardona, 1997, Phys. Rev. B 55, 12725.
- Strohm, T., D. Munzar, and M. Cardona, 1998, Phys. Rev. B 58, 8839.
- Sugai, S., and T. Hosokawa, 2000, Phys. Rev. Lett. 85, 1112.
- Sugai, S., S.-I. Shamoto, and M. Sato, 1988, Phys. Rev. B 38, 6436.
- Sugai, S., H. Suzuki, Y. Takayanagi, T. Hosokawa, and N. Hayamizu, 2003, Phys. Rev. B 68, 184504.
- Sulewski, P. E., P. A. Fleury, K. B. Lyons, and S.-W. Cheong, 1991, Phys. Rev. Lett. 67, 3864.
- Sulewski, P. E., P. A. Fleury, K. B. Lyons, S.-W. Cheong, and Z. Fisk, 1990, Phys. Rev. B 41, 225.
- Sutherland, M., S. Y. Li, D. G. Hawthorn, R. W. Hill, F. Ronning, M. A. Tanatar, J. Paglione, H. Zhang, L. Taillefer, J. DeBenedictus, R. Liang, D. A. Bonn, and W. N. Hardy, 2005, Phys. Rev. Lett. 94, 147004.
- Tallon, J. L., and J. W. Loram, 2006, Physica C 349, 53.
- Tanner, D. B., and H. J. Sievers, 1973, Phys. Rev. B 8, 1978.
- Tassini, L., Q. M. Zhang, F. Venturini, R. Hackl, F. Kikugawa, and S.-W. Fujita, 2005, Phys. Rev. Lett. 95, 117002.
- Thomsen, C., 1991, in Light Scattering in Solids VI, edited by M. Cardona and G. Güntherodt (Springer-Verlag, Berlin), p. 285.
- Thomsen, C., and M. Cardona, 1989, in Physical Properties of High Temperature Superconductors, edited by D. M. Ginsberg (World Scientific, Singapore), p. 409.
- Tilley, D. R., 1972, Z. Phys. 254, 71.
- Timusk, T., and B. W. Statt, 1999, Rep. Prog. Phys. 62, 61.
- Tohyama, T., H. Onodera, K. Tsutsui, and S. Maekawa, 2002, Phys. Rev. Lett. 89, 257405.
- Tokura, Y., H. Takagi, and S. Uchida, 1989, Nature (London) 337, 345.
- Tranquada, J. M., B. J. Sternlieb, J. D. Axe, Y. Nakamura, and S. Uchida, 1995, Nature (London) 375, 561.
- Tranquada, J. M., H. Woo, T. G. Perring, H. Goka, G. D. Gu, G. Xu, M. Fujita, and K. Yamada, 2004, Nature (London) 429, 534.
- Tranquada, J. M., 2005, e-print cond-mat/0512115.
- Triscone, G., J.-Y. Genoud, T. Graf, A. Junod, and J. Muller, 1991, Physica C 176, 247.
- Tsuei, C. C., and J. R. Kirtley, 2000, Rev. Mod. Phys. 72, 969.
- Turlakov, M., and A. Leggett, 2001, Phys. Rev. B 63, 064518.
- Tüttő, I., and A. Zawadowski, 1992, Phys. Rev. B 45, 4842.
- Uchida, S., T. Ido, H. Takagi, T. Arima, Y. Tokura, and S. Tajima, 1991, Phys. Rev. B 43, 7942.
- Valla, T., A. V. Fedorov, P. D. Johnson, P.-A. Glans, C. McGuinness, K. E. Smith, E. Y., Andrei, and H. Berger, 2004, Phys. Rev. Lett. 92, 086401.
- van Dongen, P. G. J., 1992, Phys. Rev. B 45, 2267.
- Van Harlingen, D. J., 1995, Rev. Mod. Phys. 67, 515.
- van Loosdrecht, P. H. M., J. P. Boucher, G. Martinez, G. Dhalenne, and A. Revclovschi, 1996, Phys. Rev. Lett. 76, 311.
- Varma, C. M., 1989, Physica C 162-164, 303.
- Varma, C. M., 1997, Phys. Rev. B 55, 14554.
- Varma, C. M., P. B. Littlewood, S. Schmitt-Rink, E. Abrahams, and A. E. Ruckenstein, 1989, Phys. Rev. Lett. 63, 1996.
- Venturini, F., R. Hackl, and U. Michelucci, 2003, Phys. Rev. Lett. 90, 149701.
- Venturini, F., U. Michelucci, T. P. Devereaux, and A. Kampf, 2000, Phys. Rev. B 62, 15204.
- Venturini, F., M. Opel, T. P. Devereaux, J. K. Freericks, I. Tüttő, B. Revaz, E. Walker, H. Berger, L. Forró, and R. Hackl, 2002, Phys. Rev. Lett. 89, 107003.
- Venturini, F., M. Opel, R. Hackl, H. Berger, L. Forró, and B. Revaz, 2002, J. Phys. Chem. Solids 63, 2345.
- Venturini, F., Q.-M. Zhang, R. Hackl, A. Lucarelli, S. Lupi, M. Ortolani, P. Calvani, N. Kikugawa, and T. Fujita, 2002, Phys. Rev. B 66, 060502.
- Verkin, B. I., and B. G. Lazarev, 1948, Izv. Akad. Nauk SSSR, Ser. Fiz. 12, 598.
- Vershinin, M., S. Misra, S. Ono, Y. Abe, Y. Ando, and A. Yazdani, 2004, Science 303, 1995.
- Virosztek, A., and J. Ruvalds, 1991, Phys. Rev. Lett. 67, 1657.
- Virosztek, A., and J. Ruvalds, 1992, Phys. Rev. B 45, 347.
- Vojta, M., 2003, Rep. Prog. Phys. 66, 2069.
- Wakimoto, S., H. Zhang, K. Yamada, I. Swainson, H. Kim, and R. J. Birgeneau, 2004, Phys. Rev. Lett. 92, 217004.
- Wang, D.-W., and S. Das Sarma, 1999, Phys. Rev. Lett. 83, 816.
- Wang, D.-W., and S. Das Sarma, 2002, Phys. Rev. B 65, 125322.
- Wang, D.-W., A. J. Millis, and S. Das Sarma, 2004, Phys. Rev. B 70, 165101.
- Weber, W., 1984, Physica B & C 126, 217.
- Wipf, H., M. V. Klein, B. S. Chandrasekhar, T. H. Geballe, and J. H. Wernick, 1978, Phys. Rev. Lett. 41, 1752.
- Wolff, P. A., 1966, Phys. Rev. Lett. 16, 225.
- Wolff, P. A., 1968, Phys. Rev. 171, 436.
- Worlock, J. M., A. Pinczuk, Z. J. Tien, C. H. Perry, H. L. Störmer, R. Dingle, A. C. Gossard, W. Wiegmann, and R. Aggarwal, 1981, Solid State Commun. 32, 867.
- Wu, M. K., J. R. Ashburn, C. J. Torng, P. H. Hor, R. L. Meng, L. Gao, Z. J. Huang, Y. Q. Wang, and C. W. Chu, 1987, Phys. Rev. Lett. 58, 908.
- Wu, W., and J. P. Carbotte, 1997, Phys. Rev. B 56, 6327.
- Wu, W., and A. Griffin, 1995a, Phys. Rev. B 51, 1190.
- Wu, W., and A. Griffin, 1995b, Phys. Rev. B 52, 7742.
- Wu, W., and A. Griffin, 1996, Phys. Rev. B 54, 6539.
- Wu, W. C., and J. P. Carbotte, 1998, Phys. Rev. B 57, R5614.
- Xu, Z. A., N. P. Ong, Y. Wang, T. Kageshita, and S. Uchida, 2000, Nature (London) 406, 486.
- Yamamoto, K., T. Katsufuji, T. Tanabe, and Y. Tokura, 1998, Phys. Rev. Lett. 80, 1493.
- Yamamoto, K., T. Kimura, T. Ishikawa, T. Katsufuji, and Y. Tokura, 2000, Phys. Rev. B 61, 14706.
- Yamanaka, A., N. Asayama, T. Furutani, K. Inoue, and S. Takekawa, 1996, Proc. SPIE 2696, 276.
- Yamanaka, A., T. Kimura, F. Minami, K. Inoue, and S. Takekawa, 1988, Jpn. J. Appl. Phys., Part 2 27, L1902.
- Yamanaka, A., H. Takato, F. Minami, K. Inoue, and S. Takekawa, 1992, Phys. Rev. B 46, 516.
- Yang, I.-S., M. V. Klein, S. L. Cooper, P. C. Canfield, B. K. Cho, and S.-I. Lee, 2000, Phys. Rev. B 62, 1291.
- Yang, I.-S., M. V. Klein, T. P. Devereaux, I. R. Fisher, and P. C. Canfield, 2000, Physica C 341-348, 2259.
- Yoon, S., H. L. Liu, G. Schollerer, S. L. Cooper, P. D. Han, D. A. Payne, S.-W. Cheong, and Z. Fisk, 1998, Phys. Rev. B 58, 2795.
- Yoon, S., M. Rübhausen, S. L. Cooper, K. H. Kim, and S.-W. Cheong, 2000, Phys. Rev. Lett. 85, 3297.
- Yoshida, T., X. J. Zhou, T. Sasagawa, W. L. Yang, P. V. Bogdanov, A. Lanzara, Z. Hussain, T. Misokawa, A. Fujimori, H. Eisaki, Z.-X. Shen, T. Kakeshita, and S. Uchida, 2003, Phys. Rev. Lett. 91, 027001.
- Zaanen, J., and O. Gunnarsson, 1989, Phys. Rev. B 40, 7391.
- Zasadzinski, J., 2002, in The Physics of Supreconductors Vol. I, edited by K. H. Bennemann and J. B. Ketterson (Springer-Verlag, Berlin), p. 591.
- Zawadowski, A., and M. Cardona, 1990, Phys. Rev. B 42, 10732.
- Zawadowski, A., J. Ruvalds, and J. Solana, 1972, Phys. Rev. A 5, 399.
- Zeyher, R., 2003, Phys. Rev. Lett. 90, 107002.
- Zeyher, R., and A. Greco, 2002, Phys. Rev. Lett. 89, 177004.
- Zhou, T., K. Syassen, M. Cardona, J. Karpinski, and E. Kaldis, 1996, Solid State Commun. 99, 669.
- Zhou, X. J., T. Yoshida, D.-H. Lee, W. L. Yang, V. Brouet, F. Zhou, W. X. Ti, J. W. Xiong, Z. X. Zhao, T. Sasagawa, T. Kakeshita, H. Eisaki, S. Uchida, A. Fujimori, Z. Hussain, and Z.-X. Shen, 2004, Phys. Rev. Lett. 92, 187001.