PyCCE: A Python Package for Cluster Correlation Expansion Simulations of Spin Qubit Dynamic

TL;DR

PyCCE is an open-source Python library that simulates spin qubit dynamics in a spin bath using the cluster-correlation expansion method, facilitating realistic and versatile quantum coherence studies.

Contribution

PyCCE introduces a comprehensive Python package for simulating spin qubit dynamics with realistic bath generation and both conventional and generalized CCE methods.

Findings

Calculated Hahn-echo coherence time of NV centers in diamond.

Determined coherence times of divacancies in silicon carbide.

Analyzed magnetic field effects on shallow donor dynamics.

Abstract

We present PyCCE, an open-source Python library to simulate the dynamics of spin qubits in a spin bath, using the cluster-correlation expansion (CCE) method. PyCCE includes modules to generate realistic spin baths, employing coupling parameters computed from first principles with electronic structure codes, and enables the user to run simulations with either the conventional or generalized CCE method. We illustrate three use cases of the Python library: the calculation of the Hahn-echo coherence time of the nitrogen vacancy in diamond; the calculation of the coherence time of the basal divacancy in silicon carbide at avoided crossings; and the magnetic field orientation-dependent dynamics of a shallow donor in silicon. The complete documentation and installation instructions are available at https://pycce.readthedocs.io/en/latest/.