近日，巴西巴伊亚联邦大学的Massimo Ostilli与意大利罗马大学的Carlo Presilla合作并取得一项新进展。经过不懈努力，他们量子退火的不同视角研究了态空间中的有限温度量子凝聚现象。相关研究成果已于2023年8月8日在国际知名学术期刊《物理评论A》上发表。
该研究团队证明，最近在零温度下引入的凝聚量子相变可以通过用相应的自由能代替基态能自然地扩展到有限温度。研究人员在范例Grover模型和一维非均匀晶格中的自由费米子系统中说明了这一准则。与预期的普遍特征一致，两个系统显示出结构相似的相图。最后，研究人员解释了如何使用有限温度凝聚量子相变来构建量子退火炉，在有限温度下，系统大小的输出概率指数接近1。作为例子，他们再次考虑Grover模型和费米子系统，后者是目前异质结构技术所能达到的。
据悉，在自然界中，一切都发生在有限的温度下，量子相变（QPTs）也不例外。尽管如此，它们仍然主要是在零温度下讨论和阐述的。
附：英文原文
Title: Finite-temperature quantum condensations in the space of states: A different perspective on quantum annealing
Author: Massimo Ostilli, Carlo Presilla
Issue&Volume: 2023/08/08
Abstract: In nature, everything occurs at finite temperature, and quantum phase transitions (QPTs) cannot be an exception. Nevertheless, they are still mainly discussed and formulated at zero temperature. We show that the condensation QPTs recently introduced at zero temperature can naturally be extended to finite temperature just by replacing ground-state energies with corresponding free energies. We illustrate this criterion in the paradigmatic Grover model and in a system of free fermions in a one-dimensional inhomogeneous lattice. In agreement with expected universal features, the two systems show structurally similar phase diagrams. Last, we explain how finite-temperature condensation QPTs can be used to construct quantum annealers having, at finite temperature, output probability exponentially close to 1 in the system size. As examples we consider again the Grover model and the fermionic system, the latter being well within the reach of present heterostructure technology.
DOI: 10.1103/PhysRevA.108.022205
Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.108.022205
来源：科学网 小柯机器人