| name | integrability-breaking-quantum-chaos |
| description | Quantitative theory for integrability-to-chaos transition in quantum many-body systems via tunable integrability-breaking gates. Use when analyzing OTOC crossover from integrable to chaotic regimes, computing butterfly velocity and front broadening, studying characteristic time/length scales of chaos emergence, or modeling free fermion circuits doped with non-integrable gates. |
| metadata | {"arxiv_id":"2607.02506","published":"2026-07-02","authors":"Sounak Biswas, Sthitadhi Roy, Roderich Moessner","tags":["quantum-chaos","OTOC","integrability-breaking","butterfly-velocity","free-fermion","many-body"]} |
Integrability-Breaking Quantum Chaos Theory
Core Framework
Quantitative theory for emergence of quantum many-body chaos as integrability is broken via tunable parameter. In circuit model of free fermions 'doped' with tunable density of integrability-breaking gates, microscopic mechanisms underpin crossover from early-time integrable behavior to late-time chaos.
Key Methodology
Pattern 1: Integrability-Breaking Gate Doping
- Start with free fermion circuit (integrable baseline)
- Add tunable density of integrability-breaking gates as local hotspots
- Each gate locally amplifies OTOCs in spacetime neighborhood
- Accumulation of hotspots → fully-developed chaos
Pattern 2: OTOC Crossover Analysis
- Identify explicit characteristic time and length scales governing integrable→chaotic crossover
- Extract butterfly velocity from OTOC front propagation
- Measure front broadening as function of integrability-breaking parameter
- OTOC growth rate ∝ density of integrability-breaking gates
Pattern 3: Scale Identification
- Crossover time: when accumulated hotspots percolate through system
- Butterfly velocity: speed of information front propagation
- Front broadening: dispersion of OTOC wavefront
Activation Keywords
- integrability breaking quantum chaos
- OTOC crossover free fermion
- butterfly velocity quantum circuit
- quantum chaos characteristic scales
- tunable integrability breaking
- quantum many-body chaos transition
- 量子多体混沌可积性破缺