Half-integer Shapiro steps in strong ferromagnetic Josephson junctions

@article{Yao2021HalfintegerSS,
  title={Half-integer Shapiro steps in strong ferromagnetic Josephson junctions},
  author={Yunyan Yao and Ranran Cai and See-Hun Yang and Wenyu Xing and Yang Ma and Michiyasu Mori and Yuan Ji and Sadamichi Maekawa and Xin-Cheng Xie and Wei Han},
  journal={Physical Review B},
  year={2021}
}
  • Yunyan Yao, Ranran Cai, +7 authors Wei Han
  • Published 10 September 2021
  • Physics
  • Physical Review B
We report the experimental observation of half-integer Shapiro steps in the strong ferromagnetic Josephson junction (Nb-NiFe-Nb) by investigating the current-phase relation under radiofrequency microwave excitation. The half-integer Shapiro steps are robust in a wide temperature range from T = 4 to 7 K. The half-integer Shapiro steps could be attributed to co-existence of 0and π-states in the strong ferromagnetic NiFe Josephson junctions with the spatial variation of the 

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