Spinon excitations in the quasi-one-dimensional S=1/2 chain compound Cs4CuSb2Cl12

Article

关键词: THERMODYNAMIC PROPERTIES;    MAGNETIC-SUSCEPTIBILITY;    PEIERLS TRANSITION;    THERMAL-CONDUCTIVITY;    QUANTUM CRITICALITY;    HEAT;    SR2CUO3;    SYSTEMS;    MODEL;    GAP;   

DOI  :  10.1103/PhysRevB.101.235107

来源: SCIE

【 摘 要 】

The spin-1/2 Heisenberg antiferromagnetic chain is ideal for realizing one of the simplest gapless quantum spin liquids (QSLs), supporting a many-body ground state whose elementary excitations are fractional fermionic excitations called spinons. Here we report the discovery of such a one-dimensional (1D) QSL in Cs4CuSb2Cl12. Compared to previously reported S = 1/2 1D chains, this material possesses a wider temperature range over which the QSL state is stabilized. We identify spinon excitations extending at T > 0.8 K, with a large T-linear contribution to the specific heat, gamma = 31.5(2) mJ mol(-1 )K(-2), which contribute itinerantly to thermal transport up to temperatures as high as T = 35 K. At T = 0.7 K, we find a second-order phase transition that is unchanged by a mu H-0 = 5T magnetic field. Cs4CuSb2Cl12 reveals new phenomenology deep in the 1D QSL regime, supporting a gapped QSL phase over a wide temperature range compared to many other experimental realizations.

【 授权许可】

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