1992 Fiscal Year Final Research Report Summary

Structural phase transition in the heavy fermion system Cu_6Ce

Research Project

Project/Area Number	02650470
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Physical properties of metals
Research Institution	Waseda University
Principal Investigator	KOYAMA Yasumasa Waseda University School of Science and Engineering Associate Professor, 理工学部, 助教授 (20150295)
Project Period (FY)	1990 – 1992
Keywords	Cu_6Ce / Transmission electron microscopy / One-dimensional modulated structure / In-situ observation
Research Abstract	In the present work, crystallographic features of phase transition in The heavy fermion system CeCu_6 have been in detail investigated by means of transmission electron microscopy equipped with both liquid nitrogen and liquid helium reservoirs. Specimens for electron microscopy were prepared by an ion-thinning method. When the temperature is lowered, a one-dimensional modulated structure appears around 170 K instead of the orthorhombic-to-monoclinic transition reported so far. Features of the modulated structure are that a direction of the modulation is nearly parallel to the [410] direction and its period is about 15 nm at 104 K. Further, a physical origin of the appearance of the modulated structure is discussed in relation to both a lattice softening of the elastic constant C_<66> and lattice defects introduced during the preparation of the specimen by the ion-thinning method.

(2 results)