A LONE code for the sparse control of quantum systems

In many applications with quantum spin systems, control functions with a sparse and pulse-shaped structure are often required. These controls can be obtained by solving quantum optimal control problems with L1-penalized cost functionals. In this paper, the MATLAB package LONE is presented aimed to solving L1-penalized optimal control problems governed by unitary-operator quantum spin models. This package implements a new strategy that includes a globalized semi-smooth Krylov-Newton scheme and a continuation procedure. Results of numerical experiments demonstrate the ability of the LONE code in computing accurate sparse optimal control solutions. Program summary Program title: LONE Catalogue identifier: AEYV-v1-0 Program summary URL:http://cpc.cs.qub.ac.UK/summaries/AEYV-v1-0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.UK/licence/licence.html No. of lines in distributed program, including test data, etc.: 1683 No. of bytes in distributed program, including test data, etc.: 8654 Distribution format: tar.gz Programming language: MATLAB - (OCTAVE). Computer: Any capable of running MATLAB or OCTAVE. Operating system: Any capable of running MATLAB or OCTAVE. RAM: Bytes Classification: 4.9. External routines: gmres MATLAB routine Nature of problem: A semi-smooth Newton scheme for solving quantum spin-12 sparse optimal control problems. Solution method: Full-complex semi-smooth Newton method and continuation techniques Running time: 60-600 sec.