Possible quantum paraelectric state in Kitaev spin liquid candidate H3LiIr2O6  

作　　者：Shuai Wang Long Zhang Fa Wang 

机构地区：[1]International Center for Quantum Materials,School of Physics,Peking University,Beijing 100871,China [2]Kavli Institute for Theoretical Sciences and CAS Center for Excellence in Topological Quantum Computation,University of Chinese Academy of Sciences,Beijing 100190,China [3]Physical Science Laboratory,Huairou National Comprehensive Science Center,Beijing 101400,China [4]Collaborative Innovation Center of Quantum Matter,Beijing 100871,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2020年第11期109-114,共6页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Key Basic Research Program of China(Grant No.2014CB920902);the National Key Research and Development Program of China(Grant Nos.2017YFA0302904,and 2018YFA0305800);the National Natural Science Foundation of China(Grant No.11804337);the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB28000000);the Beijing Municipal Science&Technology Commission(Grant No.Z181100004218001)。

摘　　要：A new quantum spin liquid(QSL)candidate material H3LiIr2O6 was synthesized recently and was found not to show any magnetic order or phase transition down to low temperatures.In this work,we study the quantum dynamics of the hydrogen ions,i.e.,protons,in this material by combining first-principles calculations and theoretical analysis.We show that each proton and its adjacent oxygen ions form an electric dipole.The dipole interactions and the proton tunneling are captured by a transverse-field Ising model with a quantum disordered paraelectric ground state.The dipole excitations have an energy gap△d=60 meV,and can be probed by the infrared optical spectroscopy and the dielectric response.We argue that the electric dipole fluctuations renormalize the magnetic interactions in H3LiIr2O6 and lead to a Kitaev QSL state.

关 键 词：spin liquid Kitaev material quantum paraelectricity first-principles calculations 

分 类 号：O469[理学—凝聚态物理]