YbCu2Si2–LaCu2Si2 Solid Solutions with Enhanced Thermoelectric Power Factors
Cryogenic Peltier coolers are ideal for cooling infrared sensors on satellites. To make these thermoelectric devices a realistic option for this application, the efficiency of thermoelectric materials at cryogenic temperatures must be substantially enhanced. Intermediate valence Yb-based compounds have large peaks in the Seebeck coefficient at low temperatures; to optimize these materials this must be understood. We created solid solutions between the intermediate valence compound YbCu2Si2 and an isostructural compound LaCu2Si2 to manipulate the temperature at which the Seebeck coefficient peaks and to maximize zT by reduction of lattice thermal conductivity. An enormous power factor of 110 μW/cm K2 at 100 K and a maximum zT of 0.14 at 125 K were achieved for one of these solid solutions.
KeywordsYbCu2Si2 intermediate valence thermoelectric properties solid solutions
Unable to display preview. Download preview PDF.
- 5.M.B. Maple, L.E. DeLong, and B.C. Sales, Handbook on the Physics and Chemistry of Rare Earths, Vol. 1, ed. K.A. Gschneidner and L. Eyring (Amsterdam: Elsevier, 1978), p. 797.Google Scholar
- 7.K. Alami-Yadri, H. Wilhelm, and D. Jaccard, Phys. B Condens. Matter 259–261, 157 (1999).Google Scholar
- 11.Dung, N. D. et al. J. Phys. Soc. Jpn. 78, 084711 (2009)Google Scholar
- 12.W. Franz, A. Grießel, F. Steglich, and D. Wohlleben, Z. Für Phys. B Condens. Matter 31, 7 (1978).Google Scholar