Magnetic Study of the Lower Critical Field of Organic Superconductor λ-(BETS)₂GaCl₄

Abstract:

The lower critical field of type-II organic layered superconductor λ-(BETS)₂GaCl₄ has been estimated by magnetic measurement. In this study, the demagnetization factor of a needle-like sample shape has been taken into account for the measurements by applying external field, parallel and perpendicular to the conducting plane. The lower critical field for the field perpendicular to the conducting plane is 8(1) G, convincing the previous study. This estimation allows us to predict the ideal external field that should be applied for London penetration depth measurement by using muon-spin rotation (SR) spectroscopy.

• Periodical: Materials Science Forum (Volume 966)
• Pages: 296-301
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.966.296
• Online since: August 2019
• Authors: Dita Puspita Sari*, Koichi Hiraki, Takehito Nakano, Masayuki Hagiwara, Yasuo Nozue, Takumi Kusakawa, Akiko Hori, Ayako Yamamoto, Isao Watanabe, Yasuyuki Ishii
• Keywords: Critical Field, London Penetration Depth, Magnetization, Muon-Spin Rotation, Organic Superconductor, Superconducting Gap Symmetry

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