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arXiv · 1912.12488

Quantum emulation of coherent backscattering in a system of superconducting qubits

Ana Laura Gramajo·Dan Campbell·Bharath Kannan·David K. Kim·Alexander Melville·Bethany M. Niedzielski·Jonilyn L. Yoder·María José Sánchez·Daniel Domínguez·Simon Gustavsson·William D. Oliver
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Abstract

In condensed matter systems, coherent backscattering and quantum interference in the presence of time-reversal symmetry lead to well-known phenomena such as weak localization (WL) and universal conductance fluctuations (UCF). Here we use multi-pass Landau-Zener transitions at the avoided crossing of a highly-coherent superconducting qubit to emulate these phenomena. The average and standard deviation of the qubit transition rate exhibit a dip and peak when the driving waveform is time-reversal symmetric, analogous to WL and UCF, respectively. The higher coherence of this qubit enabled the realization of both effects, in contrast to earlier work arXiv:1204.6428, which successfully emulated UCF, but did not observe WL. This demonstration illustrates the use of non-adiabatic control to implement quantum emulation with superconducting qubits.

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Ana Laura Gramajo, Dan Campbell, Bharath Kannan, David K. Kim, Alexander Melville, Bethany M. Niedzielski, Jonilyn L. Yoder, María José Sánchez, Daniel Domínguez, Simon Gustavsson, William D. Oliver. 2020-06-05. Quantum emulation of coherent backscattering in a system of superconducting qubits. https://doi.org/10.1103/physrevapplied.14.014047

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