TNSPackage: A Fortran2003 library designed for tensor network state methods

TL;DR

TNSPackage is a Fortran2003 library that simplifies tensor network state computations by providing essential tensor operations, making TNS method implementation more accessible and efficient.

Contribution

It introduces a comprehensive Fortran2003 library for tensor operations tailored for tensor network state methods, addressing the lack of standard tools.

Findings

Simplifies coding of TNS methods in Fortran

Provides a user-friendly, flexible tensor operation library

Enhances efficiency of tensor network computations

Abstract

Recently, the tensor network states (TNS) methods have proven to be very powerful tools to investigate the strongly correlated many-particle physics in one and two dimensions. The implementation of TNS methods depends heavily on the operations of tensors, including contraction, permutation, reshaping tensors, SVD and son on. Unfortunately, the most popular computer languages for scientific computation, such as Fortran and C/C++ do not have a standard library for such operations, and therefore make the coding of TNS very tedious. We develop a Fortran2003 package that includes all kinds of basic tensor operations designed for TNS. It is user-friendly and flexible for different forms of TNS, and therefore greatly simplifies the coding work for the TNS methods.