Correlation between spin helicity and an electric polarization vector in quantum-spin chain magnet LiCu2O2.
Correlation between spin helicity and an electric polarization vector in quantum-spin chain magnet LiCu2O2.
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DOI：
10.1103/physrevlett.100.127201
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发表时间：
2008-01
影响因子：
8.6
通讯作者：
S. Seki;Yuichi Yamasaki;M. Soda;Masato Matsuura;Kazuma Hirota;Y. Tokura
中科院分区：
文献类型：
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作者：
S. Seki;Yuichi Yamasaki;M. Soda;Masato Matsuura;Kazuma Hirota;Y. Tokura
偏振中子散射的测量是在 S=1/2 链多铁性 LiCu2O2 上进行的。在沿c轴自发极化的铁电基态中，证实了bc平面中横向螺旋自旋分量的存在。当电极化方向反转时，观察到由 C_(ij)=S_(i)xS_(j) （i 和 j 是相邻自旋位点）定义的矢量自旋手性发生反转，表明自旋流模型或逆 Dzyaloshinskii-Moriya 机制甚至适用于这种 e_(g)-电子量子自旋系统。极化中子的微分散射强度与经典自旋bc-摆线结构的预期有很大差异，这意味着大量子涨落的影响。
Measurements of polarized neutron scattering were performed on a S=1/2 chain multiferroic LiCu2O2. In the ferroelectric ground state with the spontaneous polarization along the c axis, the existence of transverse spiral spin component in the bc plane was confirmed. When the direction of electric polarization is reversed, the vector spin chirality as defined by C_(ij)=S_(i)xS_(j) (i and j being the neighboring spin sites) is observed to be reversed, indicating that the spin-current model or the inverse Dzyaloshinskii-Moriya mechanism is applicable even to this e_(g)-electron quantum-spin system. Differential scattering intensity of polarized neutrons shows a large discrepancy from that expected for the classical-spin bc-cycloidal structure, implying the effect of large quantum fluctuation.