High-Temperature Fermionic Gibbs States are Mixtures of Gaussian States
- 講者Yiyi Cai 小姐 (加州理工學院)
邀請人：鐘楷閔 - 時間2025-08-04 (Mon.) 10:30 ~ 12:00
- 地點資訊所新館107演講廳
摘要
Efficient simulation of a quantum system generally relies on structural properties of the quantum state. Motivated by the recent results by Bakshi et al. on the sudden death of entanglement in high-temperature Gibbs states of quantum spin systems, we study the high-temperature Gibbs states of bounded-degree local fermionic Hamiltonians, which include the special case of geometrically local fermionic systems. We prove that at a sufficiently high temperature that is independent of the system size, the Gibbs state is a probabilistic mixture of fermionic Gaussian states. This forms the basis of an efficient classical algorithm to prepare the Gibbs state by sampling from a distribution of fermionic Gaussian states.