ruqu-core

High-performance quantum circuit simulator in pure Rust — state-vector simulation with SIMD acceleration, noise models, and multi-threading support.

Features

State-Vector Simulation — Complex128 amplitude representation for exact quantum state evolution
Universal Gate Set — H, X, Y, Z, CNOT, CZ, Toffoli, Rx, Ry, Rz, Phase, SWAP, and custom unitaries
Noise Models — Depolarizing, amplitude damping, phase damping, and custom Kraus operators
SIMD Acceleration — AVX2/NEON vectorized gate application for 2-4x speedup
Multi-Threading — Rayon-based parallelism for large qubit counts
Measurement — Single-qubit, multi-qubit, and partial measurement with state collapse
Circuit Optimization — Gate fusion, cancellation, and commutation rules

Installation

cargo add ruqu-core

With optional features:

cargo add ruqu-core --features parallel,simd

Quick Start

use ruqu_core::{QuantumState, Gate, Circuit, Simulator};

// Create a 3-qubit circuit
let mut circuit = Circuit::new(3);

// Build a GHZ state: |000⟩ + |111⟩
circuit.h(0);           // Hadamard on qubit 0
circuit.cnot(0, 1);     // CNOT: control=0, target=1
circuit.cnot(1, 2);     // CNOT: control=1, target=2

// Execute simulation
let simulator = Simulator::new();
let state = simulator.run(&circuit)?;

// Measure all qubits
let result = state.measure_all();
println!("Measured: {:03b}", result);  // Either 000 or 111

Quantum Gates

Gate	Description	Matrix
`H`	Hadamard	Creates superposition
`X`	Pauli-X (NOT)	Bit flip
`Y`	Pauli-Y	Bit + phase flip
`Z`	Pauli-Z	Phase flip
`CNOT`	Controlled-NOT	Two-qubit entanglement
`CZ`	Controlled-Z	Controlled phase
`Rx(θ)`	X-rotation	Rotate around X-axis
`Ry(θ)`	Y-rotation	Rotate around Y-axis
`Rz(θ)`	Z-rotation	Rotate around Z-axis
`SWAP`	Swap qubits	Exchange qubit states
`Toffoli`	CCX	Three-qubit AND gate

Performance

Benchmarks on Apple M2 (single-threaded):

Qubits	Gates	Time
10	100	0.3ms
15	100	8ms
20	100	250ms
25	100	8s

With --features parallel on 8 cores, 20+ qubits see 3-5x speedup.

Noise Simulation

use ruqu_core::noise::{NoiseModel, Depolarizing};

let noise = NoiseModel::new()
    .add_single_qubit(Depolarizing::new(0.01))  // 1% error rate
    .add_two_qubit(Depolarizing::new(0.02));    // 2% for CNOT

let noisy_state = simulator.run_noisy(&circuit, &noise)?;

Related Crates

ruqu-algorithms — VQE, Grover, QAOA, Surface Code
ruqu-exotic — Quantum-classical hybrid algorithms
ruqu-wasm — WebAssembly bindings

Architecture

Part of the RuVector ecosystem. See ADR-QE-001 for design decisions.

License

MIT OR Apache-2.0

ruqu-core 2.0.3