75As-NQR study of the hybridization gap semiconductor CeOs4As12

TMU International Symposium on "New Quantum Phases Emerging from Novel Crystal Structure"

Yogi, M.^1 ; Higa, N.^2 ; Niki, H.^1 ; Kawata, T.^3 ; Sekine, C.^3

Department of Physics and Earth Sciences, Faculty of Science, University of the Ryukyus, Nishihara, Okinawa

903-0213, Japan^1

Graduate School of Science, University of the Ryukyus, Nishihara, Okinawa

903-0213, Japan^2

Graduate School of Engineering, Muroran Institute of Technology, Muroran, Hokkaido

050-8585, Japan^3

关键词: C-f hybridization;    Density of state;    High pressure;    Hybridization gap;    Nuclear quadrupole resonance measurements;    Nuclear spin lattice relaxation rate;    Spectrum shape;    Temperature dependence;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/683/1/012030/pdf
DOI  :  10.1088/1742-6596/683/1/012030

来源: IOP

【 摘 要 】

We performed an75As nuclear quadrupole resonance (NQR) measurement on CeOs4As12. The75As-NQR spectrum shape demonstrates that the Ce-site filling fraction of our high-pressure synthesized sample is close to unity. A presence of the c - f hybridization gap is confirmed from the temperature dependence of the nuclear spin-lattice relaxation rate 1/T1. An increase of 1/T1below ∼3 K indicates a development of the spin fluctuations. The 1/T1for CeOs4As12shows similar behavior as that for CeOs4Sb12with different magnitude of the c - f hybridization gap. An absence of phase transition in CeOs4As12may be caused by the increase of the c - f hybridization, which increases the gap magnitude and reduces the residual density of state inside the gap.