Optimal Quantum Circuit Design via Unitary Neural Networks
M. Zomorodi, H. Amini, M. Abbaszadeh, J. Sohrabi, V. Salari, P. Plawiak
TL;DR
The paper tackles the challenge of translating quantum algorithms into hardware-ready circuits by training a neural network with unitary weights to learn the input–output mapping of a quantum computation, effectively constructing a unitary $U$ with $UU^\dagger = I$ that can be transpiled into a gate-level circuit. The authors explore representations of quantum circuits via gate sequences and unitary matrices, and implement a training regime that enforces unitarity, using Gram-Schmidt to project updates back into the unitary group $U(n)$. They demonstrate near-perfect generalization to unseen inputs across multiple circuit configurations (random, entanglement, and full-adders) and discuss data availability and scalability to multi-layer designs. This data-driven approach offers a practical pathway for quantum logic synthesis by learning circuit functionality directly from input-output mappings and then leveraging transpilation for hardware compatibility.
Abstract
The process of translating a quantum algorithm into a form suitable for implementation on a quantum computing platform is crucial but yet challenging. This entails specifying quantum operations with precision, a typically intricate task. In this paper, we present an alternative approach: an automated method for synthesizing the functionality of a quantum algorithm into a quantum circuit model representation. Our methodology involves training a neural network model using diverse input-output mappings of the quantum algorithm. We demonstrate that this trained model can effectively generate a quantum circuit model equivalent to the original algorithm. Remarkably, our observations indicate that the trained model achieves near-perfect mapping of unseen inputs to their respective outputs.
