论文标题
SU的第二个谐波光谱中的非线性磁电磁性的特征（2）对称性损坏量子多体系统
Signatures of nonlinear magnetoelectricity in second harmonic spectra of SU(2) symmetry broken quantum many-body systems
论文作者
论文摘要
使用SU（2）对称性的Hubbard Hamiltonian，以SU（2）对称性破坏（SOC）或Spin-Phonon耦合的形式，对小分子系统进行了二阶动力学（ME）敏感性的量子机械扰动表达。这些敏感性将在第二个谐波发电光谱中具有签名。我们证明SU（2）对称性破坏是产生这些敏感性的关键。我们已经通过使用兰开斯方法解决了低谎言激发态的哈密顿量来计算这些ME系数。在Hubbard术语中与SOC强度变化时，我们发现了自旋和电荷，并且均以旋转电荷为主的动态ME系数光谱。我们已经表明，当哈伯德项和SOC耦合项的幅度在相似范围内时，光谱中峰的强度最高。
Quantum mechanical perturbative expressions for second order dynamical magnetoelectric (ME) susceptibilities have been derived and calculated for a small molecular system using the Hubbard Hamiltonian with SU(2) symmetry breaking in the form of spin-orbit coupling (SOC) or spin-phonon coupling. These susceptibilities will have signatures in second harmonic generation spectra. We show that SU(2) symmetry breaking is the key to generate these susceptibilities. We have calculated these ME coefficients by solving the Hamiltonian for low lying excited states using Lanczos method. Varying the Hubbard term along with SOC strength, we find spin and charge and both spin-charge dominated spectra of dynamical ME coefficients. We have shown that intensities of the peaks in the spectra are highest when the magnitudes of Hubbard term and SOC coupling term are in similar range.
