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IEEE International System-on-Chip Conference (SOCC)

Cyclic QFP Network with Controllable Bistability for Scalable Superconducting Spin Systems

Ayisat Adedokun, Selçuk Köse

Published Sep 29, 2025• 1 citation
Publisher

Abstract

A cyclically coupled network of four quantum flux parametrons (QFPs) demonstrating controllable bistable dynamics under deterministic current control is presented. Each QFP-SQUID is inductively linked to its neighbors through external superconducting inductors arranged in a closed-loop topology. Despite opposing local bias currents, the system exhibits synchronized state transitions when driven by a time-varying DC ramp, indicating strong inter-device interaction. Phase evolution measurements confirm stable and phase-locked switching behavior governed by the coupling structure. These results validate the design as a scalable superconducting network for robust state control with potential applications in memory, security, and programmable logic.

DOI
10.1109/socc66126.2025.11235377

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A cyclically coupled network of four quantum flux parametrons (QFPs) demonstrating controllable bistable dynamics under deterministic current control is presented. Each QFP-SQUID is inductively linked to its neighbors through external superconducting inductors arranged in a closed-loop topology. Despite opposing local bias currents, the system exhibits synchronized state transitions when driven by a time-varying DC ramp, indicating strong inter-device interaction. Phase evolution measurements confirm stable and phase-locked switching behavior governed by the coupling structure. These results validate the design as a scalable superconducting network for robust state control with potential applications in memory, security, and programmable logic.
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