With the current formula, the Hubbard–Stratonovich transformation is not necessary, accordingly the determinant calculation is not needed, which can improve the computational efficiency. The results show that, the simulation time has the square-law scaling with system sizes, which is comparable with ...
和Hubbard-Stratonovich transformation对应起来看就是，原先最初的电子是具有四次项相互作用的，Hubbard-Stratonovich transformation引入玻色场解耦最初的拉氏量，使得电子与电子的相互作用项转变为电子与玻色场的相互作用。接下来积掉电子部分得到玻色场的有效理论，通过鞍点近似去check玻色场是否真的condense（即发生自发...
Hubbard-Stratonovich Transformation 掷骰子的肖 编辑于 2023年10月20日 21:41 收录于文集 Theory of Interacting Electrons · 8篇 在介绍更专门的话题前(focus在铜氧化物和重费米子体系,顺便介绍一下磁性系统中的量子相变),我想更细致地梳理一下Hubbard-Stratonovich Transformatio这个方法,因为以后需要不停地使用。
罗景 作者 谢谢问题。新场的意义取决于定义\rho的时候所选择的channel。进行H-S变换之后,系统变成了一些"free" particles moving in a collective fluctuating effective field.比如如果你选了direct channel,新场描述的就是density fluctuation;如果你考虑超导,选了cooper channel,新场描述的就是超导的order parameter flu...
Erratum: Discrete Hubbard-Stratonovich transformation for fermion lattice models Erratum : Discrete hubbard-stratonovich transformation for fermion lattice models. Phys. Rev. B 29, 4159 (1984).J. E. Hirsch, Erratum: Discrete Hubbard-Stratonovich transformation for fermion lattice models, Phys. Rev. B...
这个指数平方的无穷的求和并不容易处理,可用如下高斯积分等式的转化,即Hubbard-Stratonovich transformation 可把指数平方的形式转化其一次项,代价是引入了新的一个变量,即把相互作用的体系转变为无相互作用但和额外的field有作用的体系 (decoupling)。配分函数可重写为 ...
Hubbard modelsorbital degeneracyA discrete Hubbard-Stratonovich transformation is presented for systems with an orbital degeneracy $N$ and a Hubbard Coulomb interaction without multiplet effects. An exact transformation is obtained by introducing an external field which takes $N+1$ values. Alternative ...
The Hubbard-Stratonovich transformation allows one to formulate the problem of calculating the ground state properties of a many-body theory as one of sampling a distribution. This distribution is constructed by propagating a trial wave function under the influence of a one-body time-dependent ...
The Hubbard - Stratonovich transformation of many - body theory is reconsidered in various versions. Learning from its failures in coping with competing channels of collective phenomena, a combined Hubbard - Stratonovich transformation is proposed to overcome these difficulties. That yields a variety of...