SeCQC: An open-source program code for the numerical Search for the classical Capacity of Quantum Channels

TL;DR

SeCQC is an open-source tool that numerically computes the classical capacity of quantum channels by optimizing input states and measurements using iterative gradient-based methods.

Contribution

This paper introduces SeCQC, a novel open-source software implementing an efficient numerical algorithm to determine the classical capacity of quantum channels.

Findings

Successfully computes classical capacity for various quantum channels

Uses gradient-based optimization for improved speed and accuracy

Provides an accessible tool for quantum information research

Abstract

SeCQC is an open-source program code which implements a Numerical Search for the classical Capacity of Quantum Channels (SeCQC) by using an iterative method. Given a quantum channel, SeCQC finds the statistical operators and POVM outcomes that maximize the accessible information, and thus determines the classical capacity of the quantum channel. The optimization procedure is realized by using a steepest-ascent method that fol- lows the gradient in the POVM space, and also uses conjugate gradients for speed-up.