Quantum mechanics based computing systems are expected to have high capabilities and are considered good candidates to replace classical cryptography and supercomputing systems. Among many implementations, quantum optics systems provide a promising platform to implement universal quantum computers, since they link quantum computation and quantum communication in the same framework. Recently, several quantum gates, circuits, and protocols have been experimentally realized using optics. Despite the fact that big advances in building the physical quantum computers were achieved, there are no currently available industrial computer aided tools that can perform the modeling, analysis, and verification of optical quantum computing systems. In this thesis, we tackle the idea of design automation for quantum circuits, where we use a sound language, higher order logic, to model and reason about quantum circuits formally. In particular, we propose a framework for the hierarchical modeling and automated verification of quantum computing circuits. The modeling approach captures quantum models built hierarchically from quantum gates, which models are readily available in a library. The analysis and verification of composed circuits is done seamlessly based on dedicated mathematical foundations formalized in the theorem prover. \nSpecifically, the tensor product and linear projection are used to extract the quantum circuit outputs. Subsequently, a rich library of quantum gates which includes 1-qubit, 2-qubit, and 3-qubit gates is formalized. In order to automate the analysis process, we developed a decision procedure to eliminate the need of user guidance throughout the formal proofs. To demonstrate the effectiveness of the proposed framework, we conduct the formal analysis of a benchmark of quantum circuits including the Shor's integer factorization algorithm, the Grover's oracle, and the quantum full adder.
Quantum mechanics based computing systems are expected to have high capabilities and are considered good candidates to replace classical cryptography and supercomputing systems. Among many implementations, quantum optics systems provide a promising platform to implement universal quantum computers, since they link quantum computation and quantum communication in the same framework. Recently, several quantum gates, circuits, and protocols have been experimentally realized using optics. Despite the fact that big advances in building the physical quantum computers were achieved, there are no currently available industrial computer aided tools that can perform the modeling, analysis, and verification of optical quantum computing systems. In this thesis, we tackle the idea of design automation for quantum circuits, where we use a sound language, higher order logic, to model and reason about quantum circuits formally. In particular, we propose a framework for the hierarchical modeling and automated verification of quantum computing circuits. The modeling approach captures quantum models built hierarchically from quantum gates, which models are readily available in a library. The analysis and verification of composed circuits is done seamlessly based on dedicated mathematical foundations formalized in the theorem prover. \nSpecifically, the tensor product and linear projection are used to extract the quantum circuit outputs. Subsequently, a rich library of quantum gates which includes 1-qubit, 2-qubit, and 3-qubit gates is formalized. In order to automate the analysis process, we developed a decision procedure to eliminate the need of user guidance throughout the formal proofs. To demonstrate the effectiveness of the proposed framework, we conduct the formal analysis of a benchmark of quantum circuits including the Shor's integer factorization algorithm, the Grover's oracle, and the quantum full adder.
Abstract Quantum computing systems promise to increase the capabilities for solving problems which classical computers cannot handle adequately, such as integers factorization. In this paper, we present a formal modeling and verification approach for optical quantum circuits, where we build a rich library of optical quantum gates and develop a proof strategy in higher-order logic to reason about optical quantum circuits automatically. The constructed library contains a variety of quantum gates ranging from 1-qubit to 3-qubit gates that are sufficient to model most existing quantum circuits. As real world applications, we present the formal analysis of several quantum circuits including quantum full adders and the Grover’s oracle circuits, for which we have proved the behavioral correctness and calculated the operational success rate, which has never been provided in the literature. We show through several case studies the efficiency of the proposed framework in terms of the scalability and modularity.
At the beginning of the last century, the theory of quantum optics arose and led to a revolution in physics, since it allowed the interpretation of many unknown phenomena and the development of numerous powerful, cutting edge engineering applications, \nsuch as high precision laser technology. The analysis and verification of such applications and systems, however, are very complicated. Moreover, traditional analysis tools, e.g., simulation, numerical methods, computer algebra systems, and paper-and-pencil approaches are not well suited for quantum systems. In the last decade, a new emerging verification technique, called formal methods, became common among engineering domains, and has proven to be effective as an analysis tool. Formal methods \nconsist in the development of mathematical models of the system subject for analysis, and deriving computer-aided mathematical proofs. In this thesis, we propose a framework for the analysis of quantum optics based on formal methods, in particular theorem proving. The framework aims at implementing necessary quantum mechanics and optics concepts and theorems that facilitate the modelling of quantum optical devices and circuits, and then reason about them formally. To this end, the framework \nconsists of three major libraries: 1) Mathematical foundations, which mainly contain the theory of complex-valued-function linear spaces, 2) Quantum mechanics, which develops the general rules of quantum physics, and 3) Quantum Optics, which \nspecializes these rules for light beams and implements all related concepts, e.g., light coherence which is typically emitted by laser sources. On top of these theoretical foundations, we build a library of formal models of a number of optical devices commonly \nused in quantum circuits, including, beam splitters, light displacers, and light phase shifters. Using the proposed framework, we have been able to formally verify common quantum optical computing circuits, namely the Flip gate, CNOT gate, and Mach-Zehnder interferometer.
This paper presents a novel approach to automated theorem proving specifically tailored for quantum circuit verification. The core idea is to construct a formal system that leverages logical reasoning and proof techniques to rigorously analyze quantum circuit designs. This system aims to identify errors and inconsistencies within the circuit, ensuring compliance with the fundamental principles of quantum mechanics. The proposed method moves beyond traditional circuit simulation, offering a mathematically sound guarantee of correctness. We detail the architecture of the theorem prover, focusing on the representation of quantum circuits and the application of proof strategies. The system utilizes a combination of techniques including logical deduction, model checking, and constraint solving, adapted for the unique characteristics of quantum computation. The paper outlines the key components of this system and highlights its potential to significantly improve the trustworthiness and reliability of quantum computing technologies. The central aim is to establish a robust framework for automated verification, reducing the risk of errors and accelerating the development of quantum software.
Abstract While recent progress in quantum hardware open the door for significant speedup in certain key areas, quantum algorithms are still hard to implement right, and the validation of such quantum programs is a challenge. In this paper we propose Qbricks, a formal verification environment for circuit-building quantum programs, featuring both parametric specifications and a high degree of proof automation. We propose a logical framework based on first-order logic, and develop the main tool we rely upon for achieving the automation of proofs of quantum specification: PPS, a parametric extension of the recently developed path sum semantics. To back-up our claims, we implement and verify parametric versions of several famous and non-trivial quantum algorithms, including the quantum parts of Shor’s integer factoring, quantum phase estimation (QPE) and Grover’s search.
ABSTRACT- This paper presents an integrated framework for the automated verification and visualization of quantum circuits, addressing the critical need for reliable quantum software development tools. We implement and analyze eight fundamental quantum circuits Bell states, GHZ states, Quantum Fourier Transform (QFT), Grover's search algorithm, the Variational Quantum Eigensolver (VQE) for H₂ molecules, Quantum Teleportation, Superdense Coding, and the Bernstein-Vazirani algorithm through a comprehensive verification pipeline. The system generates publication-ready circuit diagrams and performs formal verification via automated theorem proving, achieving an overall verification success rate of 93.7% across all circuits. Notably, basic circuits such as Bell and GHZ states achieve perfect verification (100% success), whereas the Quantum Teleportation circuit presents the greatest challenge, attaining only 88.9% success. Results demonstrate a strong linear correlation (R² = 0.89) between circuit complexity (gate count) and verification time, with the framework processing 348 verification conditions per second. This work establishes quantitative benchmarks for quantum software verification, highlights specific gaps in protocol-level verification, and provides an integrated toolset that bridges the gap between circuit visualization and formal correctness assurance, thereby advancing the state of quantum software engineering.
While recent progress in quantum hardware open the door for significant speedup in certain key areas, quantum algorithms are still hard to implement right, and the validation of such quantum programs is a challenge. Early attempts either suffer from the lack of automation or parametrized reasoning, or target high-level abstract algorithm description languages far from the current de facto consensus of circuit-building quantum programming languages. As a consequence, no significant quantum algorithm implementation has been currently verified in a scale-invariant manner. We propose Qbricks, the first formal verification environment for circuit-building quantum programs, featuring clear separation between code and proof, parametric specifications and proofs, high degree of proof automation and allowing to encode quantum programs in a natural way, i.e. close to textbook style. Qbricks builds on best practice of formal verification for the classical case and tailor them to the quantum case: we bring a new domain-specific circuit-building language for quantum programs, namely Qbricks-DSL, together with a new logical specification language Qbricks-Spec and a dedicated Hoare-style deductive verification rule named Hybrid Quantum Hoare Logic. Especially, we introduce and intensively build upon HOPS, a higher-order extension of the recent path-sum symbolic representation, used for both specification and automation. To illustrate the opportunity of Qbricks, we implement the first verified parametric implementations of several famous and non-trivial quantum algorithms, including the quantum part of Shor integer factoring (Order Finding - Shor-OF), quantum phase estimation (QPE) - a basic building block of many quantum algorithms, and Grover search. These breakthroughs were amply facilitated by the specification and automated deduction principles introduced within Qbricks.