Mishchenko A S, Nagaosa N
CREST, Japan Science and Technology Agency (JST), AIST, 1-1-1, Higashi, Tsukuba 305-8562, Japan.
Phys Rev Lett. 2004 Jul 16;93(3):036402. doi: 10.1103/PhysRevLett.93.036402. Epub 2004 Jul 12.
We present numeric results for ground state and angle resolved photoemission spectra (ARPES) for a single hole in the t-J model coupled to optical phonons. The systematic-error-free diagrammatic Monte Carlo method is employed where the Feynman graphs for the Matsubara Green function in imaginary time are summed up completely with respect to phonon variables, while magnetic variables are subjected to the noncrossing approximation. We obtain that at electron-phonon coupling constants relevant for high T(c) cuprates the polaron undergoes a self-trapping crossover to the strong-coupling limit and theoretical ARPES demonstrate features observed in experiment: A broad peak in the bottom of the spectra has momentum dependence which coincides with that of a hole in the pure t-J model.
我们给出了与光学声子耦合的t-J模型中单个空穴的基态和角分辨光电子能谱（ARPES）的数值结果。采用了无系统误差的图解蒙特卡罗方法，其中虚时马氏格林函数的费曼图相对于声子变量完全求和，而磁变量则采用非交叉近似。我们发现，在与高温超导体相关的电子-声子耦合常数下，极化子经历了自陷交叉到强耦合极限，理论ARPES展示了实验中观察到的特征：光谱底部的一个宽峰具有与纯t-J模型中空穴的动量依赖性相吻合的动量依赖性。
