Mickey McDonald, Jonathan Trisnadi, Kai-Xuan Yao, and Cheng Chin
Phys. Rev. X 9, 021001 (2019) - Published 1 April, 2019
A new superresolution imaging technique reveals the behavior of cold atoms in an optical lattice with a spatial resolution of 32 nm and moiré patterns that are hugely magnified images of the microscopic atomic density distribution itself.
S. Subhankar, Y. Wang, T-C. Tsui, S. L. Rolston, and J. V. Porto
Phys. Rev. X 9, 021002 (2019) - Published 1 April, 2019
A new high-resolution imaging technique reveals the behavior of individual atoms in an optical lattice with a resolution fifty times better than the conventional diffraction limit.
Shriya Pai, Michael Pretko, and Rahul M. Nandkishore
Phys. Rev. X 9, 021003 (2019) - Published 3 April, 2019
Random quantum circuits with fractonic charges, which exhibit restricted mobility, fail to thermalize after a long time, thus showing a new mechanism for achieving many-body localization.
Joseph Pollard, Gregor Posnjak, Simon Čopar, Igor Muševič, and Gareth P. Alexander
Phys. Rev. X 9, 021004 (2019) - Published 8 April, 2019
A study of chiral liquid-crystal droplets shows how defects lead to geometric arrangements similar to atoms in a molecule, and it provides a new mathematical framework for analyzing and designing novel chiral materials.
Tian Lan and Xiao-Gang Wen
Phys. Rev. X 9, 021005 (2019) - Published 10 April, 2019
A new analysis provides a way to classify topological materials with quasiparticles that act as fermions. Combined with earlier work that assumed all quasiparticles to be bosons, this offers a complete classification of all 3D topological materials.
Kuang Liu, S. Henkes, and J. M. Schwarz
Phys. Rev. X 9, 021006 (2019) - Published 10 April, 2019
Simulations explore how a packed collection of particles gains or loses rigidity. Randomly placed particles exhibit new structures underlying rigidity changes, while strategically placed particles reveal links with known structures not typically associated with rigidity.
Michael J. Gullans and David A. Huse
Phys. Rev. X 9, 021007 (2019) - Published 11 April, 2019
A theoretical analysis shows how quantum entanglement prevents thermodynamic equilibrium in systems connected to external reservoirs—a key insight for many metallic devices—and points to experiments for exploring this effect.
J.-R. Marquès, L. Lancia, T. Gangolf, M. Blecher, S. Bolaños, J. Fuchs, O. Willi, F. Amiranoff, R. L. Berger, M. Chiaramello, S. Weber, and C. Riconda
Phys. Rev. X 9, 021008 (2019) - Published 12 April, 2019
Experiments demonstrate a laser amplification technique capable of high and efficient energy transfer in under a picosecond, an essential step toward the design of next-generation extreme-intensity laser facilities.
Lennart Dabelow, Stefano Bo, and Ralf Eichhorn
Phys. Rev. X 9, 021009 (2019) - Published 15 April, 2019
A measure of irreversibility in active particle systems—such as a cluster of bacteria or a swarm of nanorobots—could be a useful metric for characterizing the out-of-equilibrium behavior of such systems.
Abhinav Prem, Sheng-Jie Huang, Hao Song, and Michael Hermele
Phys. Rev. X 9, 021010 (2019) - Published 17 April, 2019
Exactly solvable theoretical models open the door to new kinds of non-Abelian particles in quantum many-body systems.
X. Xue, T. F. Watson, J. Helsen, D. R. Ward, D. E. Savage, M. G. Lagally, S. N. Coppersmith, M. A. Eriksson, S. Wehner, and L. M. K. Vandersypen
Phys. Rev. X 9, 021011 (2019) - Published 18 April, 2019
Two-qubit quantum gates in silicon exhibit 92% fidelity when tested with a new benchmarking protocol, showing both the utility of the protocol and a promising start for developing fault-tolerant quantum computers based on spins in silicon.
L. Chomaz, D. Petter, P. Ilzhöfer, G. Natale, A. Trautmann, C. Politi, G. Durastante, R. M. W. van Bijnen, A. Patscheider, M. Sohmen, M. J. Mark, and F. Ferlaino
Phys. Rev. X 9, 021012 (2019) - Published 19 April, 2019
Experiments achieve long-lived hallmarks of supersolidity—an exotic phase of matter where superfluidity and crystalline order coexist—via two different techniques, setting the stage for future investigations into the phase’s behavior.
Junyeong Ahn, Sungjoon Park, and Bohm-Jung Yang
Phys. Rev. X 9, 021013 (2019) - Published 22 April, 2019
A new theory reveals the topological origin of the mismatch between the number of left- and right-handed Dirac quasiparticles in twisted bilayer graphene, which is a step toward identifying new topological phases of matter.
Archishman Raju, Colin B. Clement, Lorien X. Hayden, Jaron P. Kent-Dobias, Danilo B. Liarte, D. Zeb Rocklin, and James P. Sethna
Phys. Rev. X 9, 021014 (2019) - Published 23 April, 2019
Mathematical methods based on normal form theory allow for the classification of nonlinearities near critical points into families, which could help researchers better understand fractal systems.
Giuseppe Soligno and Daniel Vanmaekelbergh
Phys. Rev. X 9, 021015 (2019) - Published 23 April, 2019
Simulations identify the key parameters for directing self-assembly of nanocrystals into square or honeycomb structures, a helpful insight for realizing novel nanomaterials.
A. Grimm, F. Blanchet, R. Albert, J. Leppäkangas, S. Jebari, D. Hazra, F. Gustavo, J.-L. Thomassin, E. Dupont-Ferrier, F. Portier, and M. Hofheinz
Phys. Rev. X 9, 021016 (2019) - Published 24 April, 2019
New experiments show how to generate single microwave photons from a Josephson junction without the need for complex control electronics, a key development for quantum metrology and computing.
P. A. Maksimov, Zhenyue Zhu, Steven R. White, and A. L. Chernyshev
Phys. Rev. X 9, 021017 (2019) - Published 25 April, 2019
A theoretical overview of the phase diagram of a strongly anisotropic quantum magnet yields evidence for two interrelated spin-liquid regions and provides a framework for studies of a class of quantum materials with strong spin-orbit interactions.
Anshul D. S. Parmar, Saurabh Kumar, and Srikanth Sastry
Phys. Rev. X 9, 021018 (2019) - Published 26 April, 2019
When glass is cyclically deformed back and forth, localized bands of shear strain appear when the glass yields, but they disappear when the deformation is below some critical amount, a useful insight for understanding how solids respond to stress.
R. Santagati, A. A. Gentile, S. Knauer, S. Schmitt, S. Paesani, C. Granade, N. Wiebe, C. Osterkamp, L. P. McGuinness, J. Wang, M. G. Thompson, J. G. Rarity, F. Jelezko, and A. Laing
Phys. Rev. X 9, 021019 (2019) - Published 29 April, 2019
Machine learning enables a nitrogen-vacancy center to track a changing magnetic field with unprecedented sensitivity at room temperature, paving the way for new and practical nanoscale quantum sensing applications.
D. Afanasiev, A. Gatilova, D. J. Groenendijk, B. A. Ivanov, M. Gibert, S. Gariglio, J. Mentink, J. Li, N. Dasari, M. Eckstein, Th. Rasing, A. D. Caviglia, and A. V. Kimel
Phys. Rev. X 9, 021020 (2019) - Published 30 April, 2019
Ultrashort laser pulses induce rapid dissolution of magnetic order in a Mott insulator, demonstrating the potential these materials might have in applications requiring ultrafast magnetic dynamics.
Tatiana A. Webb, Michael C. Boyer, Yi Yin, Debanjan Chowdhury, Yang He, Takeshi Kondo, T. Takeuchi, H. Ikuta, Eric W. Hudson, Jennifer E. Hoffman, and Mohammad H. Hamidian
Phys. Rev. X 9, 021021 (2019) - Published 1 May, 2019
Scanning tunneling microscopy of cuprate crystals reveals a change between two distinct types of modulations in the electron density that could shed light on what controls exotic electronic behavior in these high-temperature superconductors.
Xiao Yan Xu, Yang Qi, Long Zhang, Fakher F. Assaad, Cenke Xu, and Zi Yang Meng
Phys. Rev. X 9, 021022 (2019) - Published 2 May, 2019
Numerical simulations provide the first concrete evidence of 2D U(1) deconfined matter, an exotic phase whose existence has been hotly pursued by both condensed-matter and high-energy physicists.
M. Malnou, D. A. Palken, B. M. Brubaker, Leila R. Vale, Gene C. Hilton, and K. W. Lehnert
Phys. Rev. X 9, 021023 (2019) - Published 3 May, 2019
Squeezed microwave vacuum allows physicists to overcome the quantum limits on cavity-based searches for axionic dark matter, enhancing detection rates twofold in a proof-of-principle experiment.
Guang Feng, Ming Chen, Sheng Bi, Zachary A. H. Goodwin, Eugene B. Postnikov, Nikolai Brilliantov, Michael Urbakh, and Alexei A. Kornyshev
Phys. Rev. X 9, 021024 (2019) - Published 6 May, 2019
Simulations show that ions in room-temperature ionic liquids can exist in two states—free and cluster-bound—with easy exchange between them, supporting one hypothesis for how these designer liquids transfer charge.
Kok Wee Song and Alexei E. Koshelev
Phys. Rev. X 9, 021025 (2019) - Published 7 May, 2019
An updated theoretical framework of a superconducting phase known as the Fulde-Ferrell-Larkin-Ovchinnikov state adds quantum-mechanical considerations that flesh out ideas about how superconductors behave in strong magnetic fields.
Colin Hubert, Yifat Baruchi, Yotam Mazuz-Harpaz, Kobi Cohen, Klaus Biermann, Mikhail Lemeshko, Ken West, Loren Pfeiffer, Ronen Rapaport, and Paulo Santos
Phys. Rev. X 9, 021026 (2019) - Published 8 May, 2019
Experiments reveal attractive dipolar interactions between two exciton fluids for the first time, establishing the anisotropic nature of the dipolar interaction between excitons—a step toward engineering and observing more complex and exotic collective quantum effects.
Krishnanand Mallayya, Marcos Rigol, and Wojciech De Roeck
Phys. Rev. X 9, 021027 (2019) - Published 9 May, 2019
A new theoretical framework provides a simple yet general mechanism for understanding prethermalization, a common but poorly understood two-step process through which some quantum gases reach thermal equilibrium.
Tuomo Tanttu, Bas Hensen, Kok Wai Chan, Chih Hwan Yang, Wister Wei Huang, Michael Fogarty, Fay Hudson, Kohei Itoh, Dimitrie Culcer, Arne Laucht, Andrea Morello, and Andrew Dzurak
Phys. Rev. X 9, 021028 (2019) - Published 10 May, 2019
Experiments show how to control the spin-orbit interaction in a double quantum-dot structure, providing a possible way to produce quantum bits with greater uniformity and improved performance.
Zhanna Samsonova, Sebastian Höfer, Vural Kaymak, Skirmantas Ališauskas, Valentina Shumakova, Audrius Pugžlys, Andrius Baltuška, Thomas Siefke, Stefanie Kroker, Alexander Pukhov, Olga Rosmej, Ingo Uschmann, Christian Spielmann, and Daniil Kartashov
Phys. Rev. X 9, 021029 (2019) - Published 14 May, 2019
A novel regime of laser-matter interaction that combines ultrashort mid-infrared laser pulses and silicon nanowires represents a promising way for producing extreme states of matter in the laboratory.
H. Duprez, E. Sivre, A. Anthore, A. Aassime, A. Cavanna, A. Ouerghi, U. Gennser, and F. Pierre
Phys. Rev. X 9, 021030 (2019) - Published 14 May, 2019
A nanoengineered circuit provides a way to increase the electron coherence length to 0.25 mm—well above previous studies—thereby setting the stage for quantum manipulation of electrons at the macroscopic scale.
G. Spektor, D. Kilbane, A. K. Mahro, M. Hartelt, E. Prinz, M. Aeschlimann, and M. Orenstein
Phys. Rev. X 9, 021031 (2019) - Published 15 May, 2019
Complex patterns of electron emission from a metal surface are controlled by exotic interactions of two forms of light carrying spin and orbital “rotations,” and they reveal internal quantum transitions within the metal.
Ryan Hamerly, Liane Bernstein, Alexander Sludds, Marin Soljačić, and Dirk Englund
Phys. Rev. X 9, 021032 (2019) - Published 16 May, 2019
A scheme for implementing optical neural networks offers the energy benefits of optical components while being scalable to large systems, promising low-energy processing with order-of-magnitude improvements in network performance.
Bruno Bertini, Pavel Kos, and Tomaž Prosen
Phys. Rev. X 9, 021033 (2019) - Published 17 May, 2019
A mathematical analysis provides the first exact computation of entanglement dynamics in chaotic quantum systems and offers a potential way to describe how entanglement spreads more generally in many-body systems.
Zhen Bi and T. Senthil
Phys. Rev. X 9, 021034 (2019) - Published 20 May, 2019
A new theoretical analysis explores quantum phase transitions in the absence of symmetry breaking and identifies several strange and surprising quantum critical phenomena.
R. Saint-Jalm, P. C. M. Castilho, É. Le Cerf, B. Bakkali-Hassani, J.-L. Ville, S. Nascimbene, J. Beugnon, and J. Dalibard
Phys. Rev. X 9, 021035 (2019) - Published 21 May, 2019
The ways in which 2D Bose gases evolve from different initial conditions are related to each other through a subtle type of symmetry, which also reveals the existence of “breathing” geometric shapes in the gas.
M. Y. Zhang, Z. X. Wang, Y. N. Li, L. Y. Shi, D. Wu, T. Lin, S. J. Zhang, Y. Q. Liu, Q. M. Liu, J. Wang, T. Dong, and N. L. Wang
Phys. Rev. X 9, 021036 (2019) - Published 22 May, 2019
Rapid pulses of laser light trigger subpicosecond phase transitions in the layered transition-metal dichalcogenide MoTe, pointing to potential realizations of ultrafast topological switches.
Michael Vogl, Pontus Laurell, Aaron D. Barr, and Gregory A. Fiete
Phys. Rev. X 9, 021037 (2019) - Published 23 May, 2019
New techniques for analyzing the response of quantum many-body systems to time-varying, periodic external fields extend current methods to the low-frequency regime, a critical step for predicting emergent novel phases.
Xingyuan Shi (侍兴源), Vojtech Nádaždy, Aleksandr Perevedentsev, Jarvist M. Frost, Xuhua Wang, Elizabeth von Hauff, Roderick C. I. MacKenzie, and Jenny Nelson
Phys. Rev. X 9, 021038 (2019) - Published 24 May, 2019
Experiments and multilevel modeling combine to reveal how different geometrical configurations of molecular units in a semiconducting polymer impact the electronic properties of the material.
L. R. Liu, J. D. Hood, Y. Yu, J. T. Zhang, K. Wang, Y.-W. Lin, T. Rosenband, and K.-K. Ni
Phys. Rev. X 9, 021039 (2019) - Published 24 May, 2019
Researchers have created a molecule in a single, precisely characterized quantum state by merging two carefully prepared atoms.
Antoine Tilloy and J. Ignacio Cirac
Phys. Rev. X 9, 021040 (2019) - Published 28 May, 2019
An extension of tensor networks—mathematical tools that simplify the study of complex quantum systems—could allow their application to a broad range of quantum field theory problems.
Muyuan Li, Daniel Miller, Michael Newman, Yukai Wu, and Kenneth R. Brown
Phys. Rev. X 9, 021041 (2019) - Published 29 May, 2019
An analysis of a family of quantum error-correcting codes provides fundamental properties and behaviors that will help in developing such codes for future robust quantum computing applications.
Eric B. Isaacs and Chris Wolverton
Phys. Rev. X 9, 021042 (2019) - Published 30 May, 2019
A deep search of a large materials database turns up 14 strongly correlated materials with electronic properties similar to cuprates, a key step toward the design and discovery of compounds with exotic behaviors such as superconductivity.
Jaewon Kim, Igor R. Klebanov, Grigory Tarnopolsky, and Wenli Zhao
Phys. Rev. X 9, 021043 (2019) - Published 31 May, 2019
A new analysis of quantum-mechanical models that describe interactions in large ensembles of Majorana fermions reveals richer phenomena in these complex systems, providing a potential path towards physical applications.
Yongkang Luo, A. Pustogow, P. Guzman, A. P. Dioguardi, S. M. Thomas, F. Ronning, N. Kikugawa, D. A. Sokolov, F. Jerzembeck, A. P. Mackenzie, C. W. Hicks, E. D. Bauer, I. I. Mazin, and S. E. Brown
Phys. Rev. X 9, 021044 (2019) - Published 31 May, 2019
Investigations of the superconductor SrRuO when mechanically stressed reveal increases in the electronic “density of states” and ferromagnetic fluctuations, both potentially important in relation to a known increase in the superconducting critical temperature.
Kenneth Rudinger, Timothy Proctor, Dylan Langharst, Mohan Sarovar, Kevin Young, and Robin Blume-Kohout
Phys. Rev. X 9, 021045 (2019) - Published 3 June, 2019
A new protocol benchmarks the stability of qubit-based processors, detecting whether quantum logic operations drift over time or are sensitive to crosstalk from neighboring qubits.
Shuang Wang, De-Yong He, Zhen-Qiang Yin, Feng-Yu Lu, Chao-Han Cui, Wei Chen, Zheng Zhou, Guang-Can Guo, and Zheng-Fu Han
Phys. Rev. X 9, 021046 (2019) - Published 4 June, 2019
A new protocol for distributing keys in a quantum network overcomes theoretical bounds for key transmission rates, potentially enabling implementation of secure communication in large networks.
Luiz H. Santos, Yuxuan Wang, and Eduardo Fradkin
Phys. Rev. X 9, 021047 (2019) - Published 5 June, 2019
A theoretical analysis provides new insight into how Majorana fermions behave in fractional quantum Hall systems, which, in turn, could lead to a better understanding of the interplay between topology and symmetry breaking in quantum matter.
A. Tamai, M. Zingl, E. Rozbicki, E. Cappelli, S. Riccò, A. de la Torre, S. McKeown Walker, F. Y. Bruno, P. D. C. King, W. Meevasana, M. Shi, M. Radović, N. C. Plumb, A. S. Gibbs, A. P. Mackenzie, C. Berthod, H. U. R. Strand, M. Kim, A. Georges, and F. Baumberger
Phys. Rev. X 9, 021048 (2019) - Published 6 June, 2019
Experiments reveal that quasiparticle properties in the superconductor SrRuO have a significant angular dependence due to the combined effects of local electron interactions and spin-orbit coupling.
Zhaoyou Wang, Marek Pechal, E. Alex Wollack, Patricio Arrangoiz-Arriola, Maodong Gao, Nathan R. Lee, and Amir H. Safavi-Naeini
Phys. Rev. X 9, 021049 (2019) - Published 7 June, 2019
Experiments demonstrate a quantum parametric oscillator, a device with great potential in quantum error correction. Its minimal hardware design makes it a suitable building block for scalable quantum computing.
Miquel Royo and Massimiliano Stengel
Phys. Rev. X 9, 021050 (2019) - Published 12 June, 2019
Combining the “long-wave method”—a mainstay of condensed-matter theory since the 1950s—with modern electronic-structure techniques allows for highly accurate predictions of physical responses of crystals to nonhomogenous external perturbations.
Chandroth P. Jisha, Alessandro Alberucci, Jeroen Beeckman, and Stefan Nolte
Phys. Rev. X 9, 021051 (2019) - Published 13 June, 2019
Using carefully tailored rotations of a transparent anisotropic medium, light can be guided without resorting to local changes in the speed of light.
Cang Zhao, Qilin Guo, Xuxiao Li, Niranjan Parab, Kamel Fezzaa, Wenda Tan, Lianyi Chen, and Tao Sun
Phys. Rev. X 9, 021052 (2019) - Published 14 June, 2019
High-resolution x-ray imaging of a laser-based manufacturing technique has captured the formation process of molten metal projectiles that produce imperfections.
Zhida Song and Xi Dai
Phys. Rev. X 9, 021053 (2019) - Published 17 June, 2019
A prediction of a new heat-transport mechanism—called chiral zero sound—may explain recent observations of a “giant” thermal conductivity in Weyl semimetals.
Di Zhou, Leyou Zhang, and Xiaoming Mao
Phys. Rev. X 9, 021054 (2019) - Published 18 June, 2019
A theoretical analysis extends concepts of topological mechanics to quasicrystals—structures that are ordered but not periodic—and finds rich new physics with potential applications to problems in condensed matter and engineering.
B. Y. Pan, H. Jang, J.-S. Lee, R. Sutarto, F. He, J. F. Zeng, Y. Liu, X. W. Zhang, Y. Feng, Y. Q. Hao, J. Zhao, H. C. Xu, Z. H. Chen, J. P. Hu, and D. L. Feng
Phys. Rev. X 9, 021055 (2019) - Published 19 June, 2019
X-ray scattering experiments on the superconductor manganese phosphide reveal two types of helical orbital arrangements that appear intertwined with the double helix of spins, suggesting that orbital physics may underlie its superconductivity.
L. R. Sletten, B. A. Moores, J. J. Viennot, and K. W. Lehnert
Phys. Rev. X 9, 021056 (2019) - Published 20 June, 2019
A device enables the detection of single quanta of sound, a step towards using them in quantum technologies.
Javier Galego, Clàudia Climent, Francisco J. Garcia-Vidal, and Johannes Feist
Phys. Rev. X 9, 021057 (2019) - Published 21 June, 2019
A theoretical analysis explores how light in a nanoscale cavity can induce chemical reactivity changes in a single simple molecule.
Severine Atis, Bryan T. Weinstein, Andrew W. Murray, and David R. Nelson
Phys. Rev. X 9, 021058 (2019) - Published 24 June, 2019
Fluid flows induced by nutrient gradients in the vicinity of microbial colonies help direct the expansion of those microbes into new territory.
Shouvik Ghorai, Philippe Grangier, Eleni Diamanti, and Anthony Leverrier
Phys. Rev. X 9, 021059 (2019) - Published 25 June, 2019
A theoretical study suggests that “continuous variable” quantum key distribution—an approach to quantum cryptography compatible with telecom networks—could be made absolutely secure against hacking.
Israel Klich, Oren Raz, Ori Hirschberg, and Marija Vucelja
Phys. Rev. X 9, 021060 (2019) - Published 26 June, 2019
A theoretical analysis reveals two types of Mpemba effects—nonequilibrium shortcuts in which a hot system cools down faster than a colder one—which can be relevant to macroscopic everyday systems.
B. Vermersch, A. Elben, L. M. Sieberer, N. Y. Yao, and P. Zoller
Phys. Rev. X 9, 021061 (2019) - Published 27 June, 2019
A new analysis tool provides details on the amount of quantum information scrambling in a system by relying on statistical correlations among measured spin states as they evolve.
Anirban Das and Anna Levina
Phys. Rev. X 9, 021062 (2019) - Published 28 June, 2019
Models for self-organized critical systems require an external driving force to be much slower than the internal dynamics. A modified model illuminates how abandoning this requirement shapes dynamics in ensembles of neurons suggested to operate close to criticality.
Xiongfeng Ma, Pei Zeng, and Hongyi Zhou
Phys. Rev. X 9, 029901 (2019) - Published 28 May, 2019