Half-integer Shapiro steps in MgB_(2) focused He ion beam Josephson junctions  

作　　者：殷大利 蔡欣炜 徐铁权 孙瑞宁 韩颖 张焱 王越 甘子钊 Dali Yin;Xinwei Cai;Tiequan Xu;Ruining Sun;Ying Han;Yan Zhang;Yue Wang;Zizhao Gan(Applied Superconductivity Center,State Key Laboratory for Mesoscopic Physics,School of Physics,Peking University,Beijing 100871,China)

机构地区：[1]Applied Superconductivity Center,State Key Laboratory for Mesoscopic Physics,School of Physics,Peking University,Beijing 100871,China

出　　处：《Chinese Physics B》2024年第8期483-489,共7页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No.12104016);the National Key Research and Development Program of China (Grant No.2020YFF01014706)。

摘　　要：Half-integer microwave induced steps(Shapiro steps)have been observed in many different Josephson junction systems,which have attracted a lot of attention because they signify the deviation of current phase relation(CPR)and uncover many unconventional physical properties.In this article,we first report the discovery of half-integer Shapiro steps in MgB_(2)focused He ion beam(He-FIB)Josephson junctions.The half-integer steps'dependence on microwave frequency,temperature,microwave power,and magnetic field is also analyzed.We find that the existence of half-integer steps can be controlled by the magnetic field periodically,which is similar to that of high temperature superconductor(HTS)grain boundary junctions,and the similarity of the microstructures between gain boundary junctions and He-FIB junctions is discussed.As a consequence,we mainly attribute the physical origin of half-integer steps in MgB_(2)He-FIB junctions to the model that a He-FIB junction is analogous to a parallel junctions'array.Our results show that He-FIB technology is a promising platform for researching CPR in junctions made of different superconductors.

关 键 词：Josephson junction half-integer Shapiro steps MgB_(2) focused helium ion beam 

分 类 号：O469[理学—凝聚态物理]