4.2. Input files for Expert mode

In this section, the details of the input files for the expert mode are explained. The input files are categorized according to the following four parts.

(1) List:
This file is a list of the input file names with the keywords. Each keyword is fixed, but the file names can be determined freely.
(2) Basic parameters:
The following input files give the basic parameters. The types of input files are determined by the keywords.
CalcMod: Set the parameters for the calculation modes.
ModPara: Set the parameters for the basic parameters, such as site number, electron number, and Lanczos step.
LocSpin: Set the location of the local spin (used only in the Kondo model).
(3) Hamiltonian:
The Hamiltonian for HPhi++ is denoted by the format of the interactions for the electron system. The types of interaction are determined by the following keywords.
Trans: The one-body part, \(c_{i\sigma_1}^{\dagger}c_{j\sigma_2}\)
InterAll: The general two-body interactions, \(c_ {i \sigma_1}^{\dagger}c_{j\sigma_2}c_{k \sigma_3}^{\dagger}c_{l \sigma_4}\).
We can set the interactions that are frequently used by the following keywords.
CoulombIntra: On-site Coulomb interactions, \(n_ {i \uparrow}n_{i \downarrow}\) (\(n_{i \sigma}=c_{i\sigma}^{\dagger}c_{i\sigma}\))
CoulombInter: Off-site Coulomb interactions, \(n_ {i}n_{j}\) (\(n_i=n_{i\uparrow}+n_{i\downarrow}\))
Hund: Hund couplings, \(n_{i\uparrow}n_{j\uparrow}+n_{i\downarrow}n_{j\downarrow}\)
PairHop: Pair hopping couplings, \(c_ {i \uparrow}^{\dagger}c_{j\uparrow}c_{i \downarrow}^{\dagger}c_{j \downarrow}\)
Exchange: Exchange couplings, \(c_ {i \uparrow}^{\dagger}c_{j\uparrow}c_{j \downarrow}^{\dagger}c_{i \downarrow}\)
Ising: Ising interactions, \(S_i~z S_j~z\)
PairLift: PairLift couplings, \(c_ {i \uparrow}^{\dagger}c_{i\downarrow}c_{j \uparrow}^{\dagger}c_{j \downarrow}\).
(4) Output:
The target for the output is determined.
OneBodyG : One-body Green’s functions, \(\langle c^{\dagger}_{i\sigma_1}c_{j\sigma_2}\rangle\)
TwoBodyG : Two-body Green’s functions, \(\langle c^{\dagger}_{i\sigma_1}c_{j\sigma_2}c^{\dagger}_{k \sigma_3}c_{l\sigma_4}\rangle\).
List file for the input files