Recent progress in high-temperature superconducting undulators

TL;DR

This paper reviews recent advances in high-temperature superconducting undulators, highlighting prototypes with high magnetic fields that enable more compact, efficient light sources for particle accelerators and free electron lasers.

Contribution

It provides a comprehensive review of recent progress and engineering developments in HTS undulators, including prototype demonstrations and future challenges.

Findings

Achieved 2.1 T magnetic field with a 10 mm period in HTS undulator

Demonstrated potential for higher-energy photon generation

Discussed engineering challenges and future opportunities

Abstract

Considerable effort has been devoted to the development of superconducting undulators (SCUs) intended for particle accelerator-based light sources, including synchrotrons and free electron laser (FEL) facilities. Recently, a high-temperature superconducting (HTS) undulator prototype, consisting of staggered-array Re-Ba-Cu-O bulks, achieved an on-axis sinusoidal magnetic field profile with a peak amplitude B$_0$ of 2.1 T and a period length of 10 mm, resulting in a deflection parameter K = 1.96. Such a short period HTS undulator not only enables the generation of higher-energy photons, but also supports the construction of economically feasible and compact FELs with shorter linear accelerators (LINACs). This article provides a comprehensive review of recent advances in the staggered-array bulk HTS undulator as well as other types of HTS undulators. Furthermore, it offers insights into the development of engineering HTS undulator prototypes designed for deployment in synchrotron and free electron laser (FEL) facilities. We conclude by discussing opportunities for and the challenges facing the use of HTS undulators in practical applications.