论文标题
二聚量子自旋系统的自旋功能重新归一化组
Spin functional renormalization group for dimerized quantum spin systems
论文作者
论文摘要
我们使用Krieg和Kopietz提出的自旋功能重新归一化组方法研究了二聚量子自旋系统[Phys。 Rev. B 99，060403（R）（2019）]直接关注物理自旋相关功能，并避免用费莫尼克或波索尼克辅助操作员表示旋转的表示。从解耦二聚体作为重新归一化组流程方程的初始条件开始，我们在所有温度下都获得了三重态激发的光谱以及量子磁磁性，铁磁和热无序相的磁化。此外，我们在三个维度上计算弱耦合二聚旋转系统的完整相图，包括两个量子临界点处的正确平均场临界指数。
We investigate dimerized quantum spin systems using the spin functional renormalization group approach proposed by Krieg and Kopietz [Phys. Rev. B 99, 060403(R) (2019)] which directly focuses on the physical spin correlation functions and avoids the representation of the spins in terms of fermionic or bosonic auxiliary operators. Starting from decoupled dimers as initial condition for the renormalization group flow equations, we obtain the spectrum of the triplet excitations as well as the magnetization in the quantum paramagnetic, ferromagnetic, and thermally disordered phases at all temperatures. Moreover, we compute the full phase diagram of a weakly coupled dimerized spin system in three dimensions, including the correct mean field critical exponents at the two quantum critical points.
