Magnetic raman scattering in two-dimensional spin-1/2 Heisenberg antiferromagnets: Spectral shape anomaly and magnetostrictive effects.
Magnetic raman scattering in two-dimensional spin-1/2 Heisenberg antiferromagnets: Spectral shape anomaly and magnetostrictive effects.
复制标题
二维自旋 1/2 海森堡反铁磁体中的磁拉曼散射：光谱形状异常和磁致伸缩效应。
DOI：
10.1103/physrevlett.75.553
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发表时间：
1995
影响因子：
8.6
通讯作者：
Dagotto
中科院分区：
文献类型：
--
作者：
Nori;Merlin;Haas;Sandvik;Dagotto
我们用精确对角化和量子蒙特卡罗方法计算了二维自旋1/2海森堡反铁磁体的拉曼光谱。在一个16位团簇上，我们考虑了声子-磁振子相互作用，它导致交换积分的随机涨落。实验结果与拉曼光谱对各种高T、C前驱体的拉曼散射实验结果吻合较好，这些前驱体包括${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{6.2}$.、CuO特别是，我们的计算重现了双磁振子峰的宽线形状，关于其最大值的不对称性，高能谱重的存在，以及名义上禁止的散射。
We calculate the Raman spectrum of the two-dimensional spin-1/2 Heisenberg antiferromagnet by exact diagonalization and quantum Monte Carlo techniques on clusters of up to 144 sites. On a 16-site cluster, we consider the phonon-magnon interaction which leads to random fluctuations of the exchange integral. Results are in good agreement with Raman scattering experiments on various high- ${T}_{c}$ precursors, such as ${\mathrm{La}}_{2}{\mathrm{CuO}}_{4}$ and ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{6.2}$. In particular, our calculations reproduce the broad line shape of the two-magnon peak, the asymmetry about its maximum, the existence of spectral weight at high energies, and the observation of nominally forbidden ${A}_{1g}$ scattering.