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arXiv · 1510.04354

Artificial quantum thermal bath: Engineering temperature for a many-body quantum system

Alireza Shabani·Hartmut Neven
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Abstract

Temperature determines the relative probability of observing a physical system in an energy state when that system is energetically in equilibrium with its environment. In this paper, we present a theory for engineering the temperature of a quantum system different from its ambient temperature. We define criteria for an engineered quantum bath that, when coupled to a quantum system with Hamiltonian $H$, drives the system to the equilibrium state $\frac{e^{-H/T}}{\rm{Tr}(e^{-H/T})}$ with a tunable parameter $T$. This is basically an analog counterpart of the digital quantum metropolis algorithm. For a system of superconducting qubits, we propose a circuit-QED approximate realization of such an engineered thermal bath consisting of driven lossy resonators. Our proposal opens the path to simulate thermodynamical properties of many-body quantum systems of size not accessible to classical simulations. Also we discuss how an artificial thermal bath can serve as a temperature knob for a hybrid quantum-thermal annealer.

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Alireza Shabani, Hartmut Neven. 2016-11-04. Artificial quantum thermal bath: Engineering temperature for a many-body quantum system. https://doi.org/10.1103/physreva.94.052301

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