Simphony

Introduction

Simphony is an open-source Python package for simulating spin dynamics in central spin systems, with a focus on nitrogen-vacancy (NV) centers coupled to nuclear spins. It provides a modular and efficient framework for building quantum registers, designing pulse sequences, and analyzing system dynamics for quantum information and sensing applications.

Key features

  • Build central spin registers by adding spins, interactions, and external fields.

  • Simulate time evolution under pulse sequences to obtain the full unitary operator.

  • Compute and visualize expectation values for chosen operators and initial states.

  • Calculate process matrices in multiple bases and frames.

  • Evaluate average gate fidelity against ideal operations.

  • Include local quasi-static noise models to study error effects.

  • Includes a predefined NV-center model with hyperfine interactions based on the Ivády Group’s hyperfine dataset.

Technical specifications

  • Built on qiskit-dynamics and jax.

  • Supports both CPU and GPU backends.

  • Accelerated by Just-in-Time (JIT) compilation via XLA.

  • Enables automatic differentiation for gradient-based optimization.

Future Plans

  • Add a predefined model for Silicon Carbide (SiC) with hyperfine interactions

  • Support multiple NV centers

  • Integrate photophysics dynamics, including initialization and readout

  • Include Lindblad-type noise models

Documentation