Elastic moduli of high-quality single-crystalline CeRu2 have been measured between 2 and 300 K by an ultrasonic technique. Both shear moduli of (C11 - C12)/2 and C44 show a giant softening without structural transition. In contrast to the shear moduli, the bulk modulus CB indicates a normal temperature dependence without the anomalous softening. These results reveal that there exists a remarkable structural fluctuation corresponding to shearing strain in the normal state of CeRu2. The analysis taking account of the deformation potential coupling between the strain and an electronic energy band demonstrates that degenerate and peaked density of states is responsible for the softening.
- Electronic band structure
- Lattice softening
- Ultrasonic measurement
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering