Quantum Criticality of the Ising-like Screw Chain Antiferromagnet SrCo2V2O8 in a Transverse Magnetic Field
Quantum Criticality of the Ising-like Screw Chain Antiferromagnet SrCo2V2O8 in a Transverse Magnetic Field
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横向磁场中类伊辛螺链反铁磁体SrCo2V2O8的量子临界性
DOI：
10.1103/physrevlett.123.067203
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发表时间：
2019-08-09
影响因子：
8.6
通讯作者：
Yu, Weiqiang
中科院分区：
文献类型：
--
作者：
Cui, Y.;Zou, H.;Yu, Weiqiang
用超低温核磁共振方法研究了沿晶轴方向施加横向磁场的Ising类螺链反铁磁体SrCo2V2O8的量子临界性。Neel温度被场迅速而连续地抑制，在H-C_1处产生了一个近似为7.03 T的量子临界点(QCP)。令人惊讶的是，从场相关的低温自旋-晶格弛豫速率1/T-51(1)的双峰结构和该场中弱的温度相关的1/T-51(1)，解析了H-C2处的第二个QCP，其特征是无间隙激发。结合数值计算，我们的数据表明，诱导的有效交错横场显著降低了临界场，并导致了H-C2处暴露的QCP，这属于一维横场的伊辛普适性。
The quantum criticality of an Ising-like screw chain antiferromagnet SrCo2V2O8, with a transverse magnetic field applied along the crystalline a axis, is investigated by ultralow temperature NMR measurements. The Neel temperature is rapidly and continuously suppressed by the field, giving rise to a quantum critical point (QCP) at H-C1 approximate to 7.03 T. Surprisingly, a second QCP at H-C2 approximate to 7.7 T featured with gapless excitations is resolved from both the double-peak structure of the field-dependent spin-lattice relaxation rate 1/T-51(1) at low temperatures and the weakly temperature-dependent 1/T-51(1) at this field. Our data, combined with numerical calculations, suggest that the induced effective staggered transverse field significantly lowers the critical fields, and leads to an exposed QCP at H-C2, which belongs to the one-dimensional transverse-field Ising universality.