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arXiv · 2206.08341

On the thermodynamic properties of fictitious identical particles and the application to fermion sign problem

Yunuo Xiong·Hongwei Xiong
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Abstract

By generalizing the recently developed path integral molecular dynamics for identical bosons and fermions, we consider the finite-temperature thermodynamic properties of fictitious identical particles with a real parameter $\xi$ interpolating continuously between bosons ($\xi=1$) and fermions ($\xi=-1$). Through general analysis and numerical experiments we find that the average energy may have good analytical property as a function of this real parameter $\xi$, which provides the chance to calculate the thermodynamical properties of identical fermions by an extrapolation with a simple polynomial function after accurately calculating the thermodynamic properties of the fictitious particles for $\xi\geq 0$. Using several examples, it is shown that our method can efficiently give accurate energy values for finite-temperature fermionic systems. Our work provides a chance to circumvent the fermion sign problem for some quantum systems.

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Yunuo Xiong, Hongwei Xiong. 2022-05-27. On the thermodynamic properties of fictitious identical particles and the application to fermion sign problem. https://doi.org/10.1063/5.0106067

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