Explicit construction of low-overhead gadgets for gates on quantum LDPC codes
Abstract
Quantum low-density parity check (QLDPC) codes can significantly reduce the overhead of quantum computing, provided the methods for performing logical operations do not require substantial space and time resources. A popular method for performing logical operations is by measuring logical Pauli operators. We present a simple, explicit construction for fixed gadgets that can measure arbitrary logical Pauli operators on QLDPC codes when dynamically connected to the code block. We apply this construction to a family of generalised bicycle codes with distances relevant to utility-scale quantum computation () and show that it reduces the space overhead by at least an order of magnitude compared to corresponding surface code architectures, without increasing the time overhead.
Keywords
Cite
@article{arxiv.2511.15989,
title = {Explicit construction of low-overhead gadgets for gates on quantum LDPC codes},
author = {Paul Webster and Samuel C. Smith and Lawrence Z. Cohen},
journal= {arXiv preprint arXiv:2511.15989},
year = {2025}
}
Comments
6 pages, 1 figure