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arXiv:2503.22897

Scalable Superconducting Nanowire Memory Array with Row-Column Addressing

Owen Medeiros, Matteo Castellani, Valentin Karam, Reed A. Foster, Alejandro Simon, Francesca Incalza, Brenden Butters, Marco Colangelo, Karl K. Berggren

Published Mar 28, 2025• 1 citation
arXivHTMLPDF

Abstract

Developing ultra-low-energy superconducting computing and fault-tolerant quantum computing will require scalable superconducting memory. While conventional superconducting logic-based memory cells have facilitated early demonstrations, their large footprint poses a significant barrier to scaling. Nanowire-based superconducting memory cells offer a compact alternative, but high error rates have hindered their integration into large arrays. In this work, we present a superconducting nanowire memory array designed for scalable row-column operation, achieving a functional density of 2.6$\,$Mb/cm$^{2}$. The array operates at $1.3\,$K, where we implement and characterize multi-flux quanta state storage and destructive readout. By optimizing write and read pulse sequences, we minimize bit errors while maximizing operational margins in a $4\times 4$ array. Circuit-level simulations further elucidate the memory cell's dynamics, providing insight into performance limits and stability under varying pulse amplitudes. We experimentally demonstrate stable memory operation with a minimum bit error rate of $10^{-5}$. These results suggest a promising path for scaling superconducting nanowire memories to high-density architectures, offering a foundation for energy-efficient memory in superconducting electronics.

DOI
10.48550/arxiv.2503.22897

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