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arXiv · 2606.16823

Physically Motivated Ansatz for Open Fermionic Systems on Quantum Computer

Yi Liu·Xiaopeng Li·Zhen Liu·Zhenyu Li
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Abstract

Determining non-equilibrium steady states (NESS) of open fermionic systems is a fundamental problem akin to finding ground states of closed systems. To address this, variational quantum algorithms can be used to solve the Lindblad master equation, much like the Schr\"odinger equation, yet ansatz design for NESS remains challenging. Existing approaches rely mostly on hardware-efficient ans\"atze (HEA), which suffer from the barren plateau problem. Here, we introduce a physically motivated ansatz named NE-UCC. Numerical simulations demonstrate that NE-UCC reliably converges to the steady state even in strongly correlated regimes far from equilibrium, reducing the infidelity by up to ten orders of magnitude compared to HEA. Furthermore, NE-UCC facilitates the exploration of excited eigenmodes with specific symmetries.

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Yi Liu, Xiaopeng Li, Zhen Liu, Zhenyu Li. 2026-06-15. Physically Motivated Ansatz for Open Fermionic Systems on Quantum Computer. https://arxiv.org/abs/2606.16823

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