Qmod: Expressive High-Level Quantum Modeling

TL;DR

Qmod is a high-level quantum programming language that enables natural expression of quantum algorithms with classical-like syntax and supports various encoding modes, aiming to improve abstraction and reusability.

Contribution

The paper introduces Qmod, a novel high-level quantum language with classical-like syntax and support for multiple encoding modes, enhancing expressiveness and automation.

Findings

Supports digital fixed-point arithmetic for resource efficiency

Includes phase and amplitude encoding modes for quantum algorithms

Demonstrates practical usage examples of Qmod language constructs

Abstract

Quantum computing hardware is advancing at a rapid pace, yet the lack of high-level programming abstractions remains a serious bottleneck in the development of new applications. Widely used frameworks still rely on gate-level circuit descriptions, causing the algorithm's functional intent to become lost in low-level implementation details, and hindering flexibility and reuse. While various high-level quantum programming languages have emerged in recent years - offering a significant step toward higher abstraction - many still lack support for classical-like expression syntax, and native constructs for useful quantum algorithmic idioms. This paper presents Qmod, a high-level quantum programming language designed to capture algorithmic intent in natural terms while delegating implementation decisions to automation. Qmod introduces quantum numeric variables and expressions, including digital fixed-point arithmetic tuned for compact representations and optimal resource usage. Beyond digital encoding, Qmod also supports non-digital expression modes - phase and amplitude encoding - frequently exploited by quantum algorithms to achieve computational advantages. We describe the language's constructs, demonstrate practical usage examples, and outline future work on evaluating Qmod across a broader set of use cases.