[Zurück]

T. Sasakawa, T. Suemitsu, T. Takabatake, Y. Bando, K. Umeo, M.H. Jung, M. Sera, T. Suzuki, T. Fujita, M. Nakajima, K. Iwasa, M. Kohgi, C. Paul, St Berger, E. Bauer:
"Successive phase transitions and energy-gap formation in CeRhAs";
Physical Review B, 66 (2002), S. 041103-1 - 041103-4.

Successive phase transitions and energy-gap formation in CeRhAs

T. Sasakawa,1 T. Suemitsu,1 T. Takabatake,1 Y. Bando,2 K. Umeo,1 M. H. Jung,1 M. Sera,1 T. Suzuki,1 T. Fujita,1 M. Nakajima,3 K. Iwasa,3 M. Kohgi,3 Ch. Paul,4 St. Berger,4 and E. Bauer4 1Department of Quantum Matter, ADSM, Hiroshima University, Higashi-Hiroshima 739-8530, Japan
2Department of Electrical Engineering, Kure National College of Technology, Kure 737-8506, Japan
3Department of Physics, Tokyo Metropolitan University, Tokyo 192-0397, Japan
4Institute of Solid State Physics, Vienna University of Technology, A-1040 Wien, Austria

(Received 10 May 2002; published 16 July 2002)

Magnetic, transport, and x-ray diffraction measurements on single-crystal CeRhAs, the so-called Kondo insulator, have revealed successive transitions at T1 = 370, T2 = 235, and T3 = 165 K. Below T1, the unit cell is doubled along the b and c axes. Thereby, the resistivity jumps upwards and magnetic susceptibility in all the directions drops. Superlattice reflections at (0,1/3,1/3) and (1/3,0,0) appear at T<T2. The latter suddenly increases below T3 where a transport gap is enhanced. These observations indicate that the gap formation is intimately related to lattice modulations. ©2002 The American Physical Society

http://link.aps.org/abstract/PRB/v66/e041103