Magnetic-field-dependent optical studies of a layered antiferromagnet Pr 1 / 2 Sr 1 / 2 MnO 3
Magnetic-field-dependent optical studies of a layered antiferromagnet Pr 1 / 2 Sr 1 / 2 MnO 3
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层状反铁磁体 Pr 1 / 2 Sr 1 / 2 MnO 3 的磁场相关光学研究
DOI：
10.1103/physrevb.62.8634
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发表时间：
2000
影响因子：
3.7
通讯作者：
X. Wei
中科院分区：
文献类型：
--
作者：
J. Jung;Hyo;T. Noh;Yutaka Moritomo;Y. Wang;X. Wei
给出了层状反铁磁体$\ensuremath{\varepsilon}(\ensuremath{\omega})$的随磁场变化的光学电导谱和介电常数谱$(A\ensuremath{-}\mathrm{t}\mathrm{y}\mathrm{p}\mathrm{e})$${\mathrm{Pr}}_{1/2}{\mathrm{Sr}}_{1/2}{\mathrm{MnO}}_{3}$。当温度为0.0T，温度为4.2K时，在远红外有一个类似Drude的小吸收峰，在中红外有一个宽的吸收峰。随着H的增加，较大的谱权从高能区向低能区转移，类Drude峰的增加。我们发现，极化子图可以解释大部分依赖于H的光谱变化。通过分析H依赖的谱重变化和$\ensuremath{\varepsilon}(\ensuremath{\omega})，，我们发现在${\mathrm{Pr}}_{1/2}{\mathrm{Sr}}_{1/2}{\mathrm{MnO}}_{3}.$中可以发生从二维金属到三维金属的空间交叉
Magnetic-field $(H)$-dependent optical conductivity spectra $\ensuremath{\sigma}(\ensuremath{\omega})$ and dielectric constant spectra $\ensuremath{\varepsilon}(\ensuremath{\omega})$ of a layered antiferromagnet $(A\ensuremath{-}\mathrm{t}\mathrm{y}\mathrm{p}\mathrm{e})$ ${\mathrm{Pr}}_{1/2}{\mathrm{Sr}}_{1/2}{\mathrm{MnO}}_{3}$ were presented. At 0.0 T in 4.2 K, the $\ensuremath{\sigma}(\ensuremath{\omega})$ showed a small Drude-like peak in the far-infrared region and a broad absorption peak in the mid-infrared region. As H increased, large spectral weights were transferred from high- to low-energy regions with increase of the Drude-like peak. We found that a polaron picture could explain most of the H-dependent spectral changes. By analyzing the H-dependent spectral weight changes and $\ensuremath{\varepsilon}(\ensuremath{\omega}),$ we showed that a dimensional crossover from a two-dimensional to a three-dimensional metal could occur in ${\mathrm{Pr}}_{1/2}{\mathrm{Sr}}_{1/2}{\mathrm{MnO}}_{3}.$