HPhi++ Documentation

Introduction

A numerical solver package for a wide range of quantum lattice models including Hubbard-type itinerant electron hamiltonians, quantum spin models, and Kondo-type hamiltonians for itinerant electrons coupled with quantum spins. The Lanczos algorithm for finding ground states and newly developed Lanczos-based algorithm for finite-temperature properties of these models are implemented for parallel computing. A broad spectrum of users including experimental researchers is cordially welcome.

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Developers

Youhei Yamaji (Quantum-Phase Electronics Center, The University of Tokyo)
Takahiro Misawa (Institute for Solid State Physics, The University of Tokyo)
Synge Todo (Department of Physics, The University of Tokyo)
Kazuyoshi Yoshimi (Institute for Solid State Physics, The University of Tokyo)
Mitsuaki Kawamura (Institute for Solid State Physics, The University of Tokyo)
Kota Ido (Department of Applied Physics, The University of Tokyo)
Naoki Kawashima (Institute for Solid State Physics, The University of Tokyo)

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Methods

• Lanczos algorithm
• Locally Optimal Block Preconditioned Conjugate Gradient (LOBPCG) method : See LOBPCG_Main()
• Thermal Pure Quantum (TPQ) state
• Full Diagonalization
• Shifted BiCG method : See CalcSpectrumByBiCG()
• Lehmann's spectral representation : See CalcSpectrumByFullDiag()

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Target models

Hubbard model, Heisenberg model, Kondo lattice model, Kitaev model, Kitaev-Heisenberg model, multi-orbital Hubbard model

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Important functions and source files

• mltply.cpp : Perform Hamiltonian-vector product
  • mltplyHubbard.cpp : For Hubbard and Kondo system
  • mltplySpin.cpp : For local spin system
• StdFace_main.cpp : Construct typical models
• global.h : Global variables
• struct.h : Binded struct

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How to modify HPhi (Developer's note)

• Coding rule
• Add new lattice model into Standard mode
• Add new input variable into Standard mode
• Global variables and Data structure
• Malloc vectors
• Add new source-file, executable, scripts (handle CMake)
• Add new calculation mode into calcmod
• Add new parameter into modpara
• Add new input-file for Expert mode
• Compute elapsed time for new functions
• Various kind of Logs
• Some contrivances for HPhi (only in Jananese) http://qlms.github.io/HPhi/develop/tips.pdf

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Link

https://github.com/QLMS/HPhi

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Download

https://github.com/QLMS/HPhi/releases

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Forum

https://github.com/QLMS/HPhi/issues

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licence

GNU GPL version 3
This software is developed under the support of "Project for advancement of software usability in materials science" by The Institute for Solid State Physics, The University of Tokyo.