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arXiv · 0902.4623

Fidelity susceptibility and quantum adiabatic condition in thermodynamic limits

Shi-Jian Gu
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Abstract

In this work, we examine the validity of quantum adiabatic theorem in thermodynamic systems. For a $d$-dimensional quantum many-body system, we show that the duration time $τ_0$ required by its ground-state adiabatic process does not depend on the microscopic details, but the scaling dimension of the fidelity susceptibility $d_a$. Our result, therefore, provides a quantitative time scale of the quantum adiabatic theorem in thermodynamic systems. The quantum adiabatic theorem might be violated in case that the scaling dimension of the fidelity susceptibility is larger than the system's real dimension ($d_a>d$).

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Shi-Jian Gu. 2009-06-22. Fidelity susceptibility and quantum adiabatic condition in thermodynamic limits. https://doi.org/10.1103/physreve.79.061125

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