Single-wall carbon nanotubes (SWCNTs) are effectively narrow ribbons of two-dimensional (2D) materials with atomically precise edges. They are ideal systems to harness quantum transport straintronics (QTS), i.e., using mechanical strain to control quantum transport. Their large sub-band energy spacing (approximately $0.8$ eV) leads to transistors with a single quantum transport channel. We adapt an applied model to study QTS in uniaxially strained quasimetallic-SWCNT transistors. The realistic device parameters are based on an existing experimental platform, with channel lengths of $L=50$ nm, diameters $d\approx 1.5$ nm, and strains up to ${\epsilon }_{\mathrm{total}}\approx 7\mathrm{\%}$. We demonstrate that the charge carrier’s propagation angle (the helix angle with respect to the tube’s axis) $\mathrm{\Theta }$ is fully tunable with ${\epsilon }_{\mathrm{total}}$. When $\mathrm{\Theta }$ reaches ${90}^{\circ }$, the conductance $G$ is completely suppressed. A strain-generated band gap can be tuned up to approximately equal to $400$ meV. Mechanical strain adds both scalar ${\varphi }_{\epsilon }$ and vector $\mathbf{\text{A}}$ gauge potentials to the transistor’s Hamiltonian. These potentials create a rich spectrum of quantum interferences in $G$, which can be described as a mechanical Aharonov-Bohm effect. The charge carriers’ quantum phase can be controlled by purely mechanical means. For instance, a full $2\pi$ phase shift can be induced in a (12,9) tube by a 0.7 $\mathrm{\%}$ strain change. This work opens opportunities to add quantitative quantum transport strain effects to the toolbox of quantum technologies based on 2D materials and their nanotubes.

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• Aharonov-Bohm effect
• Ballistic transport
• Electrical conductivity
• Quantum interference effects
• Quantum transport
• Straintronics
• Nanotubes
• Transistors