Experimental Investigation of Lee–Yang Criticality Using Non-Hermitian Quantum System  

作　　者：蓝子桁 刘文权 伍旸 叶翔宇 杨哲森 段昌奎 王亚 荣星 Ziheng Lan;Wenquan Liu;Yang Wu;Xiangyu Ye;Zhesen Yang;Chang-Kui Duan;Ya Wang;Xing Rong(CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences,University of Science and Technology of China,Hefei 230026,China;CAS Center for Excellence in Quantum Information and Quantum Physics,University of Science and Technology of China,Hefei 230026,China;Hefei National Laboratory,University of Science and Technology of China,Hefei 230088,China;School of Science,Beijing University of Posts and Telecommunications,Beijing 100876,China;Kavli Institute for Theoretical Sciences,Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences,University of Science and Technology of China,Hefei 230026,China [2]CAS Center for Excellence in Quantum Information and Quantum Physics,University of Science and Technology of China,Hefei 230026,China [3]Hefei National Laboratory,University of Science and Technology of China,Hefei 230088,China [4]School of Science,Beijing University of Posts and Telecommunications,Beijing 100876,China [5]Kavli Institute for Theoretical Sciences,Chinese Academy of Sciences,Beijing 100190,China

出　　处：《Chinese Physics Letters》2024年第5期1-11,共11页中国物理快报（英文版）

基　　金：supported by the National Key R&D Program of China (Grant No. 2021YFB3202800);the National Natural Science Foundation of China (Grant No. 12174373);the Chinese Academy of Sciences (Grant No. GJJSTD20200001);the Innovation Program for Quantum Science and Technology (Grant No. 2021ZD0302200);Anhui Initiative in Quantum Information Technologies (Grant No. AHY050000)。

摘　　要：Lee–Yang theory clearly demonstrates where the phase transition of many-body systems occurs and the asymptotic behavior near the phase transition using the partition function under complex parameters. The complex parameters make the direct investigation of Lee–Yang theory in practical systems challenging. Here we construct a non-Hermitian quantum system that can correspond to the one-dimensional Ising model with imaginary parameters through the equality of partition functions. By adjusting the non-Hermitian parameter,we successfully obtain the partition function under different imaginary magnetic fields and observe the Lee–Yang zeros. We also observe the critical behavior of free energy in vicinity of Lee–Yang zero that is consistent with theoretical prediction. Our work provides a protocol to study Lee–Yang zeros of the one-dimensional Ising model using a single-qubit non-Hermitian system.

关 键 词：FUNCTIONS PARTITION imaginary 

分 类 号：O413[理学—理论物理]