Flux-Trapping Fluxonium Qubit

TL;DR

This paper introduces a flux-trapping fluxonium qubit that uses fluxoid quantization to achieve optimal phase biasing without external magnetic flux control, simplifying large-scale quantum computing implementations.

Contribution

The work presents a novel fluxonium qubit design leveraging fluxoid quantization to eliminate the need for external flux bias lines, reducing wiring complexity and potential decoherence.

Findings

Successful phase biasing through fluxoid quantization demonstrated

Design reduces wiring overhead and crosstalk in fluxonium qubits

Potential for scalable quantum computing architectures

Abstract

In pursuit of superconducting quantum computing, fluxonium qubits have recently garnered attention for their large anharmonicity and high coherence at the sweet spot. Towards the large-scale integration of fluxonium qubits, a major obstacle is the need for precise external magnetic flux bias: To achieve high performance at its sweet spot, each qubit requires a DC bias line. However, such lines inductively coupled to the qubits bring in additional wiring overhead, crosstalk, heating, and decoherence, necessitating measures for mitigating the problems. In this work, we propose a flux-trapping fluxonium qubit, which, by leveraging fluxoid quantization, enables the optimal phase biasing without using external magnetic flux control at the operating temperature. We introduce the design and working principle, and demonstrate the phase biasing achieved through fluxoid quantization.