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arXiv · 1803.05034

Pechukas-Yukawa formalism for Landau-Zener transitions in the presence of external noise

Mumnuna A. Qureshi·Johnny Zhong·Peter Mason·Joseph J. Betouras·Alexandre M. Zagoskin
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Abstract

Quantum systems are prone to decoherence due to both intrinsic interactions as well as random fluctuations from the environment. Using the Pechukas-Yukawa formalism, we investigate the influence of noise on the dynamics of an adiabatically evolving Hamiltonian which can describe a quantum computer. Under this description, the level dynamics of a parametrically perturbed quantum Hamiltonian are mapped to the dynamics of 1D classical gas. We show that our framework coincides with the results of the classical Landau-Zener transitions upon linearisation. Furthermore, we determine the effects of external noise on the level dynamics and its impact on Landau-Zener transitions.

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Mumnuna A. Qureshi, Johnny Zhong, Peter Mason, Joseph J. Betouras, Alexandre M. Zagoskin. 2018-03-13. Pechukas-Yukawa formalism for Landau-Zener transitions in the presence of external noise. https://doi.org/10.1103/physreva.98.012128

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