Open AccessDemonstration of high‐performance pole pieces made of monocrystalline dysprosium for short‐period undulators
Author(s) -
Tanaka Takashi,
Kagamihata Akihiro
Publication year - 2019
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s1600577519006052
Subject(s) - dysprosium , monocrystalline silicon , materials science , magnet , saturation (graph theory) , magnetization , curie temperature , condensed matter physics , optics , physics , optoelectronics , magnetic field , nuclear physics , ferromagnetism , silicon , mathematics , quantum mechanics , combinatorics
Reported here are the results of experiments carried out to demonstrate the magnetic performance of dysprosium (Dy) to enhance the capability of undulators. Tiny pieces of monocrystalline Dy surrounded by permanent magnets (PMs) work as pole pieces (PPs) to concentrate the magnetic flux, when cooled down below the Curie temperature of 85 K. A PP made of Dy is much more attractive than one made of a conventional material, because its saturation magnetization is much higher. Furthermore, it also allows for a more flexible selection of PM material, potentially leading to further enhancement of the performance of short‐period undulators. Besides these advantages, practical issues related to using Dy PPs and countermeasures against them are discussed.