Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10653371 | Solid State Communications | 2005 | 6 Pages |
Abstract
Transport coefficients of quantumâwellâlike structures may in special circumstances show several interesting features. We have obtained theoretical expressions for transport coefficients including Lorenz factor and Seebeck coefficient in well-like structures taking into account the contributions from various sub-bands. Calculations based on the model have been presented for lead telluride quantum wells of varying well width (a). The results indicate a significant deviation in the transport behaviour as compared to the bulk particularly for a<100Â nm. Unlike in the bulk material changes in Lorenz factors are rather less pronounced and at a=10Â nm it is virtually a constant at 2.0. The Seebeck coefficient on the other hand shows a sharp rise below 100Â nm. This region may be of particular interest in thermoelectric device applications. The results show an unusual behaviour of the Lorenz factor and Seebeck coefficient below a 100Â nm well width. Moreover, contributions from quantized subâbands occupied up to the Fermi level may under certain conditions lead to a non-monotonic behavior which is also reported in some recent experimental measurements on particular PbTe quantum well structures.
Related Topics
Physical Sciences and Engineering
Materials Science
Materials Science (General)
Authors
M.P. Singh, C.M. Bhandari,