Channarayappa Sharath Kumar, Kumar Sankalp, Vidhyadhiraja N S, Pujari Sumiran, Saravanan M P, Sebastian Amal, Choi Eun Sang, Chikara Shalinee, Nambi Dolly, Suresh Athira, Lal Siddhartha, Jaiswal-Nagar D
School of Physics, IISER Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India.
Department of Physics, Indian Institute of Technology Bombay, Mumbai, Maharashtra 400076, India.
PNAS Nexus. 2024 Aug 23;3(9):pgae363. doi: 10.1093/pnasnexus/pgae363. eCollection 2024 Sep.
The ground state of a one-dimensional spin- uniform antiferromagnetic Heisenberg chain (AfHc) is a Tomonaga-Luttinger liquid which is quantum-critical with respect to applied magnetic fields up to a saturation field beyond which it transforms to a fully polarized state. Wilson ratio has been predicted to be a good indicator for demarcating these phases [Phys. Rev. B 96, 220401 (2017)]. From detailed temperature and magnetic field-dependent magnetization, magnetic susceptibility and specific heat measurements in a metalorganic complex and comparisons with field theory and quantum transfer matrix method calculations, the complex was found to be a very good realization of a spin- AfHc. Wilson ratio obtained from experimentally obtained magnetic susceptibility and magnetic contribution of specific heat values was used to map the magnetic phase diagram of the uniform spin- AfHc over large regions of phase space demarcating Tomonaga-Luttinger liquid, saturation field quantum critical, and fully polarized states. Luttinger parameter and spinon velocity were found to match very well with the values predicted from conformal field theory.
一维自旋 - 均匀反铁磁海森堡链（AfHc）的基态是一种汤川 - 卢廷格液体，它对于高达饱和场的外加磁场是量子临界的，超过该饱和场它会转变为完全极化态。威尔逊比率已被预测为划分这些相的良好指标[《物理评论B》96, 220401 (2017)]。通过在一种金属有机配合物中进行详细的与温度和磁场相关的磁化强度、磁化率和比热测量，并与场论和量子转移矩阵方法计算结果进行比较，发现该配合物是自旋 - AfHc的一个非常好的实例。从实验获得的磁化率和比热的磁贡献值得到的威尔逊比率，被用于在相空间的大区域绘制均匀自旋 - AfHc的磁相图，划分汤川 - 卢廷格液体、饱和场量子临界和完全极化态。发现卢廷格参数和自旋子速度与共形场论预测的值非常匹配。
