TY  - JOUR
AU  - Mi, Xinrun
AU  - Hou, De
AU  - Wang, Xiao
AU  - Hammouda, Sabreen
AU  - Liu, Caixing
AU  - Xiong, Zijian
AU  - Li, Han
AU  - Liu, Yan
AU  - Wang, Guiwen
AU  - Wang, Aifeng
AU  - Chai, Yisheng
AU  - Qi, Yang
AU  - Li, Wei
AU  - Zhou, Xiaoyuan
AU  - Su, Yixi
AU  - Khomskii, D. I.
AU  - He, Mingquan
AU  - Sheng, Zhigao
AU  - Sun, Young
TI  - Evidence for distortion-induced local electric polarization in α-RuCl3
JO  - Science China / Physics, mechanics & astronomy
VL  - 67
IS  - 9
SN  - 1674-7348
CY  - Heidelberg
PB  - Springer
M1  - FZJ-2024-05332
SP  - 297511
PY  - 2024
AB  - The spin-orbit assisted Mott insulator α-RuCl3 is a prime candidate for material realization of the Kitaev quantum spin liquid. While little attention has been paid to charge degrees of freedom, charge effects, such as electric polarization, may arise in this system. Here, we report distortion-induced local electric polarization in α-RuCl3 as evidenced by single-crystal X-ray diffraction, second harmonic generation (SHG) and dielectric measurements. The SHG signal appears at room temperature and develops substantially in the Kitaev paramagnetic state when short-range spin correlations come into play. Despite sizable pyroelectric currents in the Kitaev paramagnetic state, the absence of hysteresis in the polarization-electric field (P-E) points to the short-range nature of electric polarization. This localized electric polarization is likely the result of distortion-induced charge dimerization, achieved through virtual hopping-induced charge redistribution. In addition, the electric polarization is boosted by short-range spin correlations via spin-phonon coupling in the Kitaev paramagnetic state. Our results emphasize the importance of charge degrees of freedom in α-RuCl3, which establish a novel platform to investigate charge effects in Kitaev materials.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:001286330700005
DO  - DOI:10.1007/s11433-024-2417-8
UR  - https://juser.fz-juelich.de/record/1030509
ER  -