Momentum-Driven Reversible Logic Accelerates Efficient Irreversible Universal Computation

TL;DR

This paper demonstrates how momentum-driven reversible logic in superconducting circuits enables efficient, high-fidelity universal computation by combining reversible and irreversible logic, outperforming metastable approaches.

Contribution

It introduces a novel momentum-based approach for reversible logic that enhances speed and fidelity in superconducting quantum circuits, enabling universal computation with practical advantages.

Findings

EF outperforms metastable approach in fidelity and speed

Momentum enables simultaneous reversible and irreversible logic

Protocol is suitable for experimental realization

Abstract

We present implementations of two physically-embedded computation-universal logical operations using a 2-bit logical unit composed of coupled quantum flux parametrons -- Josephson-junction superconducting circuits. To illustrate universality, we investigate NAND gates built from these two distinct elementary operations. On the one hand, Controlled Erasure (CE) is designed using fixed-point analysis and assumes that information must be stored in locally-metastable distributions. On the other, Erasure-Flip (EF) leverages momentum as a computational resource and significantly outperforms the metastable approach, simultaneously achieving higher fidelity and faster computational speed without incurring any additional energetic cost. Notably, the momentum degree of freedom allows the EF to achieve universality by using both nontrivial reversible and irreversible logic simultaneously in different logical subspaces. These results not only provide a practical, high-performance protocol ripe for experimental realization but also underscore the broader potential of momentum-based computing paradigms.