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arXiv · 1309.6383

Classical Simulation of Quantum Noise

Daniel Crow·Robert Joynt
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Abstract

Dephasing decoherence induced by interaction of one qubit with a quantum bath can be simulated classically by random unitary evolution without the need for a bath and this random unitary evolution is equivalent to the quantum case. For a general dephasing model and a single qubit system, we explicitly construct the noise functional and completely specify the random unitary evolution. To demonstrate the technique, we applied our results to three paradigmatic models: spin-boson, central spin, and quantum impurity. For multiple qubits, we identify a class of generalized quantum dephasing models that can be simulated classically. Finally we show that depolarizing quantum models can be simulated classically for all dimensionalities of the principal system.

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Daniel Crow, Robert Joynt. 2014-04-23. Classical Simulation of Quantum Noise. https://doi.org/10.1103/physreva.89.042123

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