Acceleration of the Stochastic Analytic Continuation Method via an Orthogonal Polynomial Representation of the Spectral Function  

作　　者：WU Quan-Sheng WANG Yi-Lin FANG Zhong DAI Xi 吴泉生;王义林;方忠;戴希(Beijing National Laboratory for Condensed Matter Physics,and Institute of Physics,Chinese Academy of Sciences,Beijing 100190)

机构地区：[1]Beijing National Laboratory for Condensed Matter Physics,and Institute of Physics,Chinese Academy of Sciences,Beijing 100190

出　　处：《Chinese Physics Letters》2013年第9期1-4,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China,and the National Basic Research Program of China under Grant No 2007CB925000.

摘　　要：Stochastic analytic continuation is an excellent numerical method for analytically continuing Green’s functions from imaginary frequencies to real frequencies,although it requires significantly more computational time than the traditional MaxEnt method.We develop an alternate implementation of stochastic analytic continuation which expands the dimensionless field𝑜n(x)introduced by Beach using orthogonal polynomials.We use the kernel polynomial method(KPM)to control the Gibbs oscillations associated with truncation of the expansion in orthogonal polynomials.Our KPM variant of stochastic analytic continuation delivers improved precision at a significantly reduced computational cost.

关 键 词：CONTINUATION ANALYTIC STOCHASTIC 

分 类 号：O17[理学—数学]