Real-time instanton approach to quantum activation

A Real-time Instanton Approach to Quantum Activation

Description

This archive contains the complete computational repository for the research paper "A Real-time Instanton Approach to Quantum Activation" (arXiv:2409.00681), including all source code, documentation, and computational data files required for full reproducibility.

Contents

Source Code & Documentation:

• Python package (src/metastable/) implementing the Keldysh field theory approach
• Interactive documentation and derivations (docs/)
• Visualization scripts for all figures
• Test suite and configuration files

Computational Data Files (1.9 GB):

• docs/fixed_points/examples/map.npz (12 MB) - Basic fixed point map data
• docs/fixed_points/examples/map-with-stability.npz (233 MB) - Fixed points with stability analysis
• docs/paths/sweeps/kappa/sweep/map.npz (735 MB) - Kappa parameter sweep results
• docs/paths/sweeps/epsilon/sweep/map.npz (917 MB) - Epsilon parameter sweep results

Research Context

This work investigates quantum activation in driven dissipative systems far from equilibrium, focusing on how quantum noise associated with relaxation can lead to transitions between metastable states, even at zero temperature. The repository provides:

1. Theoretical Framework: Complete derivation of the Keldysh Lagrangian and auxiliary Hamiltonian formulation
2. Computational Methods: Implementation of fixed-point analysis and stability calculations
3. Parameter Studies: Comprehensive sweeps of system parameters (κ and ε)
4. Visualization Tools: Scripts to reproduce all figures in the publication

Usage Instructions

1. Extract Archive: unzip metastable-complete-with-data.zip
2. Install Dependencies: pip install -e . (requires Python ≥3.10)
3. Run Examples: Navigate to docs/fixed_points/examples/ or docs/paths/sweeps/
4. View Documentation: Open docs/index.md or visit the live documentation

Key Features

• Fixed Point Analysis: Calculation and classification of system fixed points in the bistable regime
• Stability Analysis: Eigenvalue analysis of the Jacobian at fixed points
• Path Integration: Implementation of switching trajectory calculations
• Interactive Visualizations: Plotly-based interactive plots for exploration

File Structure

metastable/
   ├── src/metastable/          # Core Python package
   ├── docs/                             # Documentation and examples
    │   ├── fixed_points/         # Fixed point analysis
    │   ├── paths/                     # Trajectory analysis
    │   └── derivation/             # Theoretical derivations
   ├── tests/                            # Test suite
    └── README.md               # Setup and usage instructions