QxQuark · Embeddings for Quantum Circuits

Embeddings for
Quantum Circuits

A lightweight transformer that converts quantum circuits into semantic vector representations, enabling search, deduplication, clustering, and fast equivalence filtering.

647K

Parameters

128-D

Embeddings

CPU

Fast

Open

Source

quark@quantumx:~/similarity.py

$ python similarity.py

from qiskit import QuantumCircuit
from quark import CircuitEncoder, embed
 
a = QuantumCircuit(3)
a.h(0)
a.cx(0,1)
 
b = QuantumCircuit(3)
b.h(0)
b.h(0)
b.h(0)
b.cx(0,1)
 
ea, eb = embed(model, [a, b])
print((ea * eb).sum())
# 0.96
$
Architecture

QxQuark Circuit Understanding Workflow

Transform quantum circuits into semantic vector representations for retrieval, clustering, and equivalence-aware analysis.

Quantum Circuits

Multi-Framework Ingestion

Qiskit · PennyLane · Cirq · OpenQASM

QxQuark Engine

Gate Tokenizer

Graph Neural Encoder

647K-Param Model

Vector Embeddings

Semantic Fingerprints

Similarity Metric

Nearest-Neighbor Index

Equivalence Check

Unitary Verification

CPU-Native · No GPU

PyTorch Backend

Python SDK & CLI

Deduplication

Group Equivalent Circuits

Semantic Search

Search by Example

Optimization QA

Transpiler Regression Checks

Clustering

Structural Circuit Discovery

Library Intelligence

Searchable Codebases

System Architecture & Pipeline
What it does

Key Capabilities

Semantic Search

Find circuits that compute similar operations even when implemented differently.

Circuit Deduplication

Identify duplicate circuits across repositories and benchmark datasets.

Equivalence Pre-Filtering

Filter candidates before expensive exact unitary verification.

Repository Discovery

Cluster and explore large collections of quantum circuits using embeddings.

Performance

Accelerate Quantum Circuit Analysis

0+

Circuits / Second

Generate embeddings efficiently on commodity CPU hardware.

0-D

Vector Representation

Compact semantic representation suitable for retrieval and indexing.

0

Verified Rewrite Families

Trained using equivalence-preserving circuit transformations.

The Problem

The Problem

Which of these circuits are actually the same?

Approach
Limitation
Hash Gate Strings
Breaks under equivalence-preserving rewrites.
Sort Gates
Loses important ordering information.
Gate Counts
Ignores circuit structure and qubit relationships.
Full Unitary Comparison
Exact but computationally expensive.
QxQuark
Fast semantic similarity with practical scalability.

QxQuark sits between fragile heuristics and expensive exact verification, providing fast semantic understanding of quantum circuits.

Under the hood

How QxQuark Works

01

Tokenize

Each gate becomes a structured token.

02

Embed

Learned embeddings capture gate semantics.

03

Transformer Encoder

3 layers, 4 attention heads, CLS representation.

04

Normalize

Produces a 128-dimensional unit vector.

647K

Parameters

3

Transformer Layers

4

Attention Heads

128-D

Embeddings

CPU

Optimized

Benchmarks

Benchmark Results

Real benchmark numbers with transparent reporting.

In-Distribution Recall@10

QxQuark1.00
Baseline0.88

Held-Out Rewrite Recall@10

QxQuark0.98
Baseline0.55

Gate vs Inverse Separation

QxQuark0.67
Baseline0.00

QASMBench OOD Recall@10

QxQuark0.17
Baseline0.17

Note — Ties the strongest baseline on out-of-distribution benchmarks while significantly outperforming on equivalence-aware retrieval tasks.

Research

Research Highlights

R1

Distinct Inverse Tokens

Separates S from S†, T from T†, and other inverse operations.

R2

Hard Negative Training

Improves discrimination between near-equivalent circuits.

R3

Expanded Rewrite Coverage

Supports additional verified equivalence-preserving transformations.

Applications

Industry & Research Applications

01Quantum Research Labs
02Quantum Software Platforms
03Circuit Repositories
04Compiler Validation
05Benchmark Dataset Curation
06Quantum Education Platforms
07Circuit Search Engines
08Quantum Workflow Automation
Try it

Interactive Playground

Two circuits in. One similarity score out.

Circuit A

H q0H q0H q0CX q0·q1

Circuit B

H q0CX q0·q1

Similarity Score

+1.000

Ground Truth: Equivalent

Cosine similarity between the two 128-dimensional embeddings. Scores near +1.000 indicate semantically equivalent circuits; low or negative scores indicate the circuits compute different operations.

Open Source

Open Source & Research

quark@quantumx:~
$pip install qx-quark

Build Smarter Quantum Circuit Workflows

Use semantic embeddings to search, organize, analyze, and understand quantum circuits at scale.