Kondo lattice effects of YbAl3 suggested by temperature dependence of high-accuracy high-energy photoelectron spectroscopy

• Published in: Journal of the Physical Society of Japan 2005-11, Vol.74 (11), p.2880-2884
• Main Authors: SUGA, Shigemasa, SEKIYAMA, Akira, EBIHARA, Takao, ONUKI, Yoshichika, IMADA, Shin, SHIGEMOTO, Akihiko, YAMASAKI, Atsushi, TSUNEKAWA, Masanori, DALLERA, Claudia, BRAICOVICH, Lucio, LEE, Tien-Lin, SAKAI, Osamu
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electron density of states and band structure of crystalline solids; Electron states; Exact sciences and technology; Other metals and alloys; Physics
• ISSN: 0031-9015; 1347-4073
• DOI: 10.1143/JPSJ.74.2880

By use of high-resolution soft X-rays, intrinsic temperature dependences of bulk Yb 4f photoelectron spectra were obtained for fractured surfaces of high-purity YbAl3 single crystals. The spectra of not only bulk 4f13 but also 4f12 final states are analyzed by noncrossing approximation (NCA) calculation for the f14, f13, and f12 initial states based on the single impurity Anderson model (SIAM). In order to consistently interpret the temperature dependences of both 4f13 and 4f12 final states, however, it is found that a constant set of parameters of the hybridization strength δ, bare 4f energy [straight epsilon]f and electron correlation energy Uff is insufficient. The limitation of SIAM is confirmed for YbAl3 and the importance of the Kondo lattice effects is suggested.