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Thermodynamic and Transport Properties of CeMg2Cu9 under Pressure

Masakazu Ito·Koji Asada·Yuko Nakamori·Jyun'ya Hori·Hironobu Fujii·Fumihiko Nakamura·Toshizo Fujita·Takashi Suzuki
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Abstract

We report the transport and thermodynamic properties under hydrostatic pressure in the antiferromagnetic Kondo compound CeMg2Cu9 with a two-dimensional arrangement of Ce atoms. Magnetic specific heat Cmag(T) shows a Schottky-type anomaly around 30 K originating from the crystal electric field (CEF) splitting of the 4f state with the first excited level at \Delta_{1}/kB = 58 K and the second excited level at \Delta_{2}/kB = 136 K from the ground state. Electric resistivity shows a two-peaks structure due to the Kondo effect on each CEF level around T_{1}^{max} = 3 K and T_{2}^{max} = 40 K. These peaks merge around 1.9 GPa with compression. With increasing pressure, Neel temperature TN initially increases and then change to decrease. TN finally disappears at the quantum critical point Pc = 2.4 GPa.

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Masakazu Ito, Koji Asada, Yuko Nakamori, Jyun'ya Hori, Hironobu Fujii, Fumihiko Nakamura, Toshizo Fujita, Takashi Suzuki. 2004-02-01. Thermodynamic and Transport Properties of CeMg2Cu9 under Pressure. https://doi.org/10.1143/jpsj.73.2252

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