Videos

Qudit Lifted Product Codes with Good Parameters

Presenter
April 12, 2026
Abstract
Quantum low-density parity-check (QLDPC) codes are a promising approach to achieving fault-tolerant quantum computation with low space and time overhead. While asymptotically good qubit QLDPC codes have recently been constructed via the lifted product (LP) method, the existence of analogous codes for higher dimensional qudits remained an open question, particularly for non-prime qudit dimensions. In this work, we resolve this question affirmatively by introducing a qudit generalization of the LP construction, which extends hypergraph product and lifted product codes to arbitrary qudit dimensions. We provide a detailed analysis of qudit LP codes and explore their connection to additive quantum codes to establish bounds on encoding rates. We further demonstrate that, under appropriate constraints, qudit lifted product codes form asymptotically good families with sublinear scaling of both the number of logical qudits and the minimum distance. In addition, we study decoding strategies for qudit QLDPC codes, comparing an additive decoder suitable for general qudit codes and a linear decoder optimized for fully stacked constructions. Monte Carlo simulations show that qudit codes outperform comparable qubit codes in logical error rates and that the linear decoder provides further performance gains for fully stacked codes.
Supplementary Materials