NMR evidence of charge fluctuations in multiferroic CuBr<sub>2</sub>

NMR evidence of charge fluctuations in multiferroic CuBr₂

Wang Rui-Qi^{1, 2}, Zheng Jia-Cheng², Chen Tao², Wang Peng-Shuai², Zhang Jin-Shan³, Cui Yi², Wang Chao⁴, Li Yuan⁴, Xu Sheng^{1, †}, Yuan Feng^{1, ‡}, Yu Wei-Qiang²

(color online) Zero-field ⁷⁹Br and ⁸¹Br NMR spectra at typical temperatures below T_N. Data are offset for clarity. Inset: the resonance frequencies ⁷⁹f and ⁸¹f deduced by the peaked positions, shown as functions of temperature, with scales on the left axis. Their differences ⁷⁹f –⁸¹f are shown with scales on the right axis.