Title data
Moos, Ralf ; Gnudi, Alain ; Härdtl, Karl Heinz:
Thermopower of Highly Donor Doped Sr1-xLaxTiO₃ Ceramics.
In:
Waser, Rainer (Hrsg.): Electroceramics IV : proceedings of the 4th International Conference on Electroceramics & Applications. Bd. 2. -
Aachen
: Augustinus Buchhandlung
,
1994
. - pp. 815-818
ISBN 3-86073-287-0
Abstract in another language
In this study the thermopower S of Sr1-xLaxTiO3-ceramics was investigated for 0≤x≤0.5 between 150K and 1200K for the first time. For low temperature and high x,S depends linearly on temperature and x^(-2/3), as expected from the model of a degenerated quasi free electron gas. This allows to determine the effective mass (m_eff=4.2•m_e), without assuming a transport factor A_e. In the case of high temperature and low x, |S| rises with 1.5•ln10•k/e per decade of temperature, as expected from the classical Boltzmann statistics. With m_eff deduced from degeneration, A_e=3 can be evaluated subsequently in the classical case, requiring only a temperature and lanthanum independent m_eff . Thus, thermopower of the Sr1-xLaxTiO3-ceramics can be described by a constant effective mass and a constant transport factor within a wide range of temperature and lanthanum content. Furthermore, the transition from degeneration to classical behavior can be described as a function of temperature and electron density. At room temperature, it takes place at about x≈0.2 (i.e. n≈3.4•10^21/cm3).
Further data
Item Type: | Article in a book |
---|---|
Refereed: | Yes |
Institutions of the University: | Faculties > Faculty of Engineering Science Faculties > Faculty of Engineering Science > Chair Functional Materials > Chair Functional Materials - Univ.-Prof. Dr.-Ing. Ralf Moos Faculties Faculties > Faculty of Engineering Science > Chair Functional Materials |
Result of work at the UBT: | No |
DDC Subjects: | 600 Technology, medicine, applied sciences > 620 Engineering |
Date Deposited: | 08 Jul 2015 09:08 |
Last Modified: | 08 Jul 2015 09:08 |
URI: | https://eref.uni-bayreuth.de/id/eprint/15747 |