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arXiv 0704.3632cond-mat.mtrl-scicond-mat.str-el
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多铁性Eu $_{0.75}$ Y $_{0.25}$ MnO $_3$中的巨磁振子-声子耦合

Colossal magnon-phonon coupling in multiferroic Eu$_{0.75}$Y$_{0.25}$MnO$_3$

R. Valdés Aguilar, A. B. Sushkov, C. L. Zhang, Y. J. Choi, S. -W. Cheong, H. D. Drew

摘要:

本文报道了Eu $_{0.75}$ Y $_{0.25}$ MnO $_3$的变温远红外光谱(10-250 cm $^{-1}$)的磁诱导电偶极吸收谱。这些光谱只发生在$e||a$极化中,由两个相对窄的电磁子特征和一个宽的吸收带组成,其中电磁子特征在$T_{FE}=30$ K开始,而吸收带在远高于$T_N=47$ K的温度下持续存在。所观察到的激发占步的静态介电常数在铁电相。观测到80 cm $^{-1}$处的电磁振子与附近的最低光学声子强耦合,该声子将其光谱重量的1/2以上转移到磁振子。我们把宽背景吸收的起因归结为声子的两个磁振子发射衰变过程。

英文摘要:

We report the spectra of magnetically induced electric dipole absorption in Eu$_{0.75}$Y$_{0.25}$MnO$_3$ from temperature dependent far infrared spectroscopy (10-250 cm$^{-1}$). These spectra, which occur only in the $e||a$ polarization, consist of two relatively narrow electromagnon features that onset at $T_{FE}=30$ K and a broad absorption band that persists to temperatures well above $T_N=47$ K. The observed excitations account for the step up of the static dielectric constant in the ferroelectric phase. The electromagnon at 80 cm$^{-1}$ is observed to be strongly coupled to the nearby lowest optical phonon which transfers more than 1/2 of its spectral weight to the magnon. We attribute the origin of the broad background absorption to the two magnon emission decay process of the phonon.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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