Server for computing exact ground state of Ising model with random interacitons (Ising spin glasses). Users can specify the distributions of the interactions and the geometry of lattices. By inputting the informaiont of the model, users will receive the computational results by e-mail from the server.
A free software library for numerical diagonalization of quantum spin systems. Although the programs are based on TITPACK, they have been completely rewritten in C/C++ and several extensions have been added. It can handle, for example, the Heisenberg model, the Hubbard model, and the t-J model. This library supports dimension reduction of matrices exploiting symmetries, and it can run in parallel computing environments.
A sparse-modeling tool for computing the spectral function from the imaginary-time Green function. It removes statistical errors in quantum Monte Carlo data, and performs a stable analytical continuation. The obtained spectral function fulfills the non-negativity and the sum rule. The computation is fast and free from tuning parameters.
A open-source application of first-principles calculation for the electronic structure, using the KKR method, a variant of Green’s function method. It is based on the density functional theory and is applicable to crystals and surfaces. The coherent potential approximation (CPA) is adopted, so it can handle not only periodic systems, but also disordered alloys. It can also handle spin-orbit interaction and non-collinear magnetism.
STATE is a first-principles plane-wave pseudo-potential code. It provides electronic state calculations and molecular dynamics simulations. This code is suitable for simulating chemical reactions at solid surfaces and solid–liquid interfaces, i.e., It is able to investigate reaction paths and activation barriers of chemical processes at interfaces. It can also include Van der Waals corrections to conventional density functional theory.
An open-source application for evaluating superconducting gaps from resutls of the first-principles calculation by Quantum ESPRESSO. By calculating electron-phonon interaction and screened Coulomb interaction from the first-principles calculation, superconducting gaps can be obtained from the gap equation. Quasiparticle densities of states and ultrasonic attenuation rates can also be calculated.
TC++ is open-source software for ab initio calculations using the transcorrelated (TC) method. In TC++, users can take account of electron correlations in a Jastrow correlation factor based on the TC method. Electronic structures obtained by Quantum ESPRESSO can be used as an initial state of TC++.
A solver program for two dimensional quantum lattice model based on a projected entangled pair state wavefunction and the corner transfer matrix renormalization group method.
This works on a massively parallel machine because tensor operations are OpenMP/MPI parallelized.
A Python library for simulating strongly correlated quantum systems using tensor networks. The goal is to make the algorithms readable and easy to use for beginners, and also powerful and fast for experts. Simple sample code and toy code to illustrate TEBD and DMRG are also provided.
Automatic generation tool for codes of tensor contraction. This tool can automatically generate codes of an optimal computing sequence for construction of a single tensor from a tensor network composed of tensors. Netcon algorithm proposed by Pfeifer et al. is used, and it is possible to search optimal solution quickly. Generated codes are available in Numpy and mptensor in Python.