THA2WC01
Kyoto University, Kyoto, Japan
Generation of strong periodic magnetic field in short period is important technology for future advanced light sources such as free electron lasers and synchrotron radiation facilities. However, the period length and K-value of undulators are limited by the maximum energy product of permanent magnet or engineering critical current density of superconducting wire in general. In order to overcome these technological limit, use of bulk superconductor has been proposed. The critical current densities of rare earth barium copper oxide (REBCO) exceeds 10 kA/mm2 at low temperature. This value is about 10 times higher than the engineering critical current density of superconducting wire. The maximum trapped magnetic field by REBCO bulk superconductor exceeds 17 T *,**. If this high density supercurrent are fully handled, ultra-short period high field undulator is realized. In this presentation, I will introduce several approaches of bulk superconductor undulators and summarize the merit and the drawback of them, then the potential of the bulk superconductors will be discussed.
* M. Tomita and M. Murakami, Nature 421 pp. 517'520, 2003
** J. H. Durrell et al., Supercond. Sci. Technol. 27 082001, 2014
