Single-crystalline samples of YbInCu4 and its partially substituted compounds by Y and Lu were synthesized by the flux method. The temperature dependence of the magnetic susceptibility from 2 to 320 K in the magnetic field of 0.5 T and the high-field magnetization up to 41 T under various fixed pressures were measured in order to investigate the effect of substitution, inherent chemical pressure, and external pressure on the first-order valence transition of YbInCu4. Substitution of Yb by Y or Lu results in a small increase or decrease of the lattice parameter, while both systems show a steep decrease of transition temperature (Tv) and transition magnetic field (Hv) with substitution, resulting in suppression of the valence transition around x=0.30 for Yb1-x YxInCu4 (0≤x≤0.3) and x=0.15 for Yb1-xLuxInCu4 (0≤x≤0.15). The effect of pressure on Hv of the pure and Y-substituted YbInCu4 is reported by dHv/dP≈-1 T/kbar, with a suppression of the valence transition of Yb0.8Y0.2InCu4 at the pressure of 8 kbar. The effect of inherent chemical pressure is very small compared with the intrinsic effect of substitution. The decreasing of Kondo temperature TK (∞1/X0) below Tv resulting from the substitution for the Yb lattice is discussed as an important factor affecting the valence transition of YbInCu4.
|ジャーナル||Physical Review B - Condensed Matter and Materials Physics|
|出版物ステータス||出版済み - 7 1 2002|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics