Status: Preprint on arXiv (December 2025)

Overview

QubitPulseOpt is a Python framework for quantum gate optimization using GRAPE (Gradient Ascent Pulse Engineering) with realistic noise modeling. The project demonstrates that high-fidelity quantum gate operations can be achieved through systematic pulse optimization, reaching 99.14% X-gate fidelity in 20ns simulations—a 77% error reduction compared to Gaussian baseline pulses.

Key Results

MetricValue
X-gate Fidelity99.14%
Error Reduction77% vs. Gaussian baseline
Simulation Time20ns
Unit Tests864
Code Coverage74%

Technical Approach

Noise Modeling

  • Lindblad master equation for realistic T1/T2 decoherence effects
  • Hardware-representative workflow via API connectivity to IQM Garnet 20-qubit processor for calibration retrieval
  • Microwave control pulse optimization for transmon qubits

Optimization

  • GRAPE algorithm with gradient-based pulse refinement
  • Numerical quantum state evolution using matrix exponentials
  • Multiple optimization backends (gradient descent, L-BFGS)

Software Engineering

  • Engineered following NASA JPL Power-of-10 coding standards
  • CI/CD pipeline with GitHub Actions
  • 864 unit tests, 74% code coverage
  • Modular architecture for extensibility

Technology Stack

  • Quantum Simulation: QuTiP, NumPy, SciPy
  • Optimization: GRAPE, L-BFGS, gradient descent
  • Testing: pytest, GitHub Actions CI/CD
  • Hardware Integration: IQM Garnet API

Future Integration

This project is designed to integrate with the Quantum Circuit Optimizer for end-to-end quantum compilation: from high-level circuits through gate optimization and qubit routing, down to noise-robust control pulses.

Citation

Malarchick, R. (2025). “GRAPE Pulse Optimization for Quantum Gates with Hardware-Representative Noise.” arXiv:2511.12799.