solver.green.dat

Introduction

This file is used to store the imaginary-time Green's function $G(\tau)$. It will be output by the quantum impurity solvers when they are shut down.

Format

The solver.green.dat file contains norbs block. Each block is appended by two blank lines. The format of each block is as follows:

column 1: orbital index $i$, integer

column 2: imaginary-time index $j$, integer

column 3: imaginary-time point, $\tau$, double precision

column 4: imaginary-time Green's function, $G(\tau)$, double precision

column 5: error bar, $\delta G(\tau)$, double precision

Note

In the solver.green.dat file, we adopt the following orbital sequence: $1\uparrow$, $2\uparrow$, $3\uparrow$, $\cdots$, $1\downarrow$, $2\downarrow$, $3\downarrow$, $\cdots$ In other words, the spin up part is always before the spin down part.

Code

The corresponding Fortran code block for the writing of solver.green.dat file is as follows:

! open data file: solver.green.dat
open(mytmp, file='solver.green.dat', form='formatted', status='unknown')

! write it
do i=1,norbs
    do j=1,ntime
        write(mytmp,'(2i6,3f12.6)') i, j, tmesh(j), gtau(j,i,i), gerr(j,i,i)
    enddo ! over j={1,ntime} loop
    write(mytmp,*) ! write empty lines
    write(mytmp,*)
enddo ! over i={1,norbs} loop

! close data file
close(mytmp)

In the iQIST software package, we provide a Python module to read the output files of quantum impurity solvers. You can use it to read the solver.green.dat file. See [src/tools/u_reader.py] for more details.