S = 1/2的J1-J2阻挫自旋链材料具有丰富的基态和奇特的磁性质，表现出自旋Peierls相变、多铁性、分数量子激发和外磁场中新奇的自旋向列相等有趣现象。本项目以LiCuSbO4、PbCu(SO4)(OH)2、Ca2Y2Cu5O10等典型的S = 1/2的J1-J2阻挫自旋链材料为主要研究对象，以这些材料的磁结构特征、基态磁性质以及磁场和掺杂诱导的量子相变为主要研究内容，主要使用光学浮区法或者助溶剂法生长高品质的单晶并制备化学掺杂的单晶，调节材料的磁结构和磁交换相互作用，利用低温强磁场下的磁性、比热和热输运等测量手段研究磁结构转变、量子相变机制和量子临界现象。通过这些研究揭示量子涨落、自旋阻挫、各向异性、化学掺杂等因素对磁结构、量子相变和量子临界现象所起的作用，从而拓展和深化我们对量子磁性物理的认识。

The S = 1/2 frustrated spin chain materials have rich ground states and exotic magnetic properties, and exhibit interesting phenomena, such as spin Peierls transition, multiferroicity, fractional spin excitations, novel spin nematic phases in external magnetic field. This project mainly studies S = 1/2 frustrated spin chain materials LiCuSbO4, PbCu(SO4)(OH)2, and Ca2Y2Cu5O10 and focuses on their magnetic structures, magnetic properties of ground states, and quantum phase transitions inducing by external magnetic field or chemical doping. We plan to grow high quality single crystals by optical floating zone or flux method and grow chemically doped crystals to adjust magnetic structures as well as exchange coupling constants. Magnetic structure transition, mechanism of quantum phase transitions and quantum critical phenomena will be studied by measuring magnetization, specific heat and heat transport at low temperature and in high magnetic field. These studies can reveal the roles of quantum fluctuation, spin frustration, anisotropy and chemical doping in magnetic phase transition and quantum critical phenomena, and are helpful for our understanding on quantum magnetic physics.