SchroSIM v1.0.0 — Gaussian Core with Hybrid Non-Gaussian Foundations

SchroSIM v1.0.0

This is the first stable public release of SchroSIM, a modular photonic quantum circuit simulator designed for clean separation between Gaussian and non-Gaussian simulation regimes.

What’s included

• Gaussian backend (stable)

  • Symplectic evolution of multimode Gaussian states
  • Phase, squeezing, beam splitter, and displacement gates
  • Loss and thermal-loss channels
  • Homodyne and heterodyne measurements with state conditioning

• IR-level circuit representation

  • Backend-agnostic gate IR
  • Explicit handling of measurements, noise, and non-Gaussian injection
  • Deterministic lowering rules for Gaussian unitaries

• Hybrid backend architecture

  • Automatic backend selection based on circuit content
  • Gaussian circuits routed to the Gaussian backend
  • Non-Gaussian state injection (Fock, cat) routed to the Fock backend

• Effective GKP support

  • Approximate GKP states via additive Gaussian noise
  • Enables GKP-style workflows without full non-Gaussian simulation

• Exact Fock backend (single-mode)

  • Exact Fock-space evolution with configurable cutoff
  • Supports phase and displacement operations
  • Designed as a non-Gaussian reference backend

• Robust test suite

  • Validation of symplectic structure
  • Measurement correctness
  • Loss and thermal-noise behavior
  • Hybrid backend dispatch logic

Scope and intent

This release establishes a stable architectural foundation rather than feature completeness.
True non-Gaussian dynamics beyond state injection (e.g., cubic phase gates, multi-mode Fock evolution, feed-forward) are intentionally deferred to future releases.

Versioning

• v1.0.0 is the main release
• Development landmarks are preserved as milestone/* tags for reproducibility and historical reference