Design and initial results from the "Junior" Levitated Dipole Experiment

TL;DR

The 'Junior' Levitated Dipole Experiment by OpenStar Technologies demonstrates initial plasma production using a high-temperature superconducting magnet, marking progress in fusion research with innovative superconducting and power supply technologies.

Contribution

This paper introduces the 'Junior' experiment, showcasing the integration of high-temperature superconductors and novel power supply technology in a levitated dipole fusion device.

Findings

Achieved first plasma in late 2024

Successfully integrated high-temperature superconducting magnet

Laid groundwork for future experimental campaigns

Abstract

OpenStar Technologies is a private fusion company exploring the levitated dipole concept for commercial fusion energy production. OpenStar has manufactured a new generation of levitated dipole experiment, called "Junior", leveraging recent advances made in high-temperature superconducting magnet technologies. Junior houses a ~5.6 T REBCO high-temperature superconducting magnet in a 5.2 m vacuum chamber, with plasma heating achieved via < 50 kW of electron cyclotron resonance heating power. Importantly, this experiment integrates novel high temperature superconductor power supply technology on board the dipole magnet. Recently OpenStar has completed first experimental campaigns with the Junior experiment, achieving first plasmas in late 2024. Experiments conducted with the full levitated system are planned for 2025. This article provides an overview of the main results from these experiments and details improvements planned for future campaigns.