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arXiv · 2205.05881

Shubnikov-de Haas and de Haas-van Alphen oscillation in Czochralski grown CoSi single crystal

Abstract

Anisotropic transport, Shubnikov-de Haas (SdH), and de Haas-van Alphen (dHvA) quantum oscillations studies are reported on a high-quality CoSi single crystal grown by the Czochralski method. Temperature-dependent resistivities indicate the dominating electron-electron scattering. Magnetoresistance (MR) at 2 K reaches 610% for I||[111] and B||[01-1], whereas it is 500% for I||[01-1] and B||[111]. A negative slope in field-dependent Hall resistivity suggests electrons are the majority carriers. The carrier concentration extracted from Hall conductivity indicates no electron-hole compensation. In 3D CoSi, the electron transport lifetime is found to be approximately in the same order as quantum lifetime, whereas in 2D electron gas the long-range scattering drives the transport life much larger than the quantum lifetime. From linear and Hall SdH oscillations the effective masses and Dingle temperatures have been calculated. The dHvA oscillation reveals three frequencies at 18 ($γ$), 558 ($α$) and 663 T ($β$)), whereas, SdH oscillation results in only two frequencies $α$ and $β$. The $γ$ frequency observed in dHvA oscillation is a tiny hole pocket at the $Γ$ point.

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BibTeXRIS

Souvik Sasmal, Gourav Dwari, Bishal Baran Maity, Vikas Saini, Rajib Mondal, A. Thamizhavel. 2022-05-12. Shubnikov-de Haas and de Haas-van Alphen oscillation in Czochralski grown CoSi single crystal. https://doi.org/10.1088/1361-648x%2Fac8960

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