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arXiv · 1512.07120

Observation of Unusual Magnetoelastic Effects in a Quasi-1D Spiral Magnet

Chong Wang·Daiwei Yu·Xiaoqiang Liu·Rongyan Chen·Xinyu Du·Biaoyan Hu·Lichen Wang·Kazuki Iida·Kazuya Kamazawa·Shuichi Wakimoto·Ji Feng·Nanlin Wang·Yuan Li
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Abstract

We present a systematic study of spin and lattice dynamics in the quasi-one-dimensional spiral magnet CuBr2, using Raman scattering in conjunction with infrared and neutron spectroscopy. Along with the development of spin correlations upon cooling, we observe a rich set of broad Raman bands at energies that correspond to phonon-dispersion energies near the one-dimensional magnetic wave vector. The low-energy bands further exhibit a distinct intensity maximum at the spiral magnetic ordering temperature. We attribute these unusual observations to two possible underlying mechanisms: (1) formation of hybrid spin-lattice excitations, and/or (2) "quadrumerization" of the lattice caused by spin-singlet entanglement in competition with the spiral magnetism.

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Chong Wang, Daiwei Yu, Xiaoqiang Liu, Rongyan Chen, Xinyu Du, Biaoyan Hu, Lichen Wang, Kazuki Iida, Kazuya Kamazawa, Shuichi Wakimoto, Ji Feng, Nanlin Wang, Yuan Li. 2017-07-13. Observation of Unusual Magnetoelastic Effects in a Quasi-1D Spiral Magnet. https://doi.org/10.1103/physrevb.96.085111

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