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arXiv · 1610.01105

Systematic Magnus-based approach for suppressing leakage and non-adiabatic errors in quantum dynamics

Hugo Ribeiro·Alexandre Baksic·Aashish A. Clerk
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Abstract

We present a systematic, perturbative method for correcting quantum gates to suppress errors that take the target system out of a chosen subspace. It addresses the generic problem of non-adiabatic errors in adiabatic evolution and state preparation, as well as general leakage errors due to spurious couplings to undesirable states. The method is based on the Magnus expansion: by correcting control pulses, we modify the Magnus expansion of an initially-given, imperfect unitary in such a way that the desired evolution is obtained. Applications to adiabatic quantum state transfer, superconducting qubits and generalized Landau-Zener problems are discussed.

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Hugo Ribeiro, Alexandre Baksic, Aashish A. Clerk. 2016-10-04. Systematic Magnus-based approach for suppressing leakage and non-adiabatic errors in quantum dynamics. https://doi.org/10.1103/physrevx.7.011021

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