# Persistent Currents in Superconducting Quantum Interference Devices

## TL;DR

This paper develops a quantum model of a two-junction superconducting quantum interference device, revealing persistent currents and proposing a supercurrent qubit in the quantum regime.

## Contribution

It introduces a quantum analog of the classical device by deriving eigenvalues of the Hamiltonian, extending its properties into the quantum domain.

## Key findings

- Eigenvalues of the Hamiltonian reveal persistent currents.
- Quantum analog acts as a supercurrent qubit with negligible capacitance.
- Model extends classical device behavior to quantum regime.

## Abstract

Starting from the reduced dynamical model of a two-junction quantum interference device, a quantum analog of the system has been exhibited, in order to extend the well known properties of this device to the quantum regime. By finding eigenvalues of the corresponding Hamiltonian operator, the persistent currents flowing in the ring have been obtained. The resulting quantum analog of the overdamped two-junction quantum interference device can be seen as a supercurrent qubit operating in the limit of negligible capacitance and finite inductance.

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Source: https://tomesphere.com/paper/0704.0546