Magnon drag and the low temperature thermopower of GeMnTe

1978 ◽  
Vol 56 (5) ◽  
pp. 497-500
Author(s):  
A. Cafaro ◽  
F. T. Hedgcock ◽  
W. B. Muir
Keyword(s):  
Low Temperature ◽  
Experimental Evidence ◽  
Thermoelectric Power ◽  
Low Temperatures ◽  
Impurity Scattering ◽  
Experimental Results ◽  
Phonon Drag ◽  
Degenerate Semiconductors ◽  
Upper Limit

The thermoelectric power of pure GeTe and GeMnTe containing 1 and 5at.% Mn has been measured between 25 and 2.5 K. The manganese doped Ge–Te alloys ferromagnetically order at low temperatures and theoretical estimates of the magnon drag contribution to the thermopower in these degenerate semiconductors is 60 μV/K. When appropriate allowance is made for the effects of impurity scattering on the phonon drag thermopower there appears to be no experimental evidence for a magnon drag contribution to the thermopower of this magnitude. An upper limit for the magnon drag contribution to the thermopower estimated from the experimental results for these materials is 0.5 μV/K.

THE THERMOELECTRIC POWER OF ANNEALED AND COLD-WORKED SILVER AND GOLD AT LOW TEMPERATURES

1960 ◽  
Vol 38 (8) ◽  
pp. 1048-1058 ◽  
Author(s):  
W. B. Pearson
Keyword(s):  
Low Temperature ◽  
Thermoelectric Power ◽  
Low Temperatures ◽  
Phonon Drag ◽  
Scattering Mechanisms ◽  
Cold Worked

Most of the low-temperature thermoelectric behavior of annealed and cold-worked silver and gold samples can be accounted for satisfactorily by using Kohler's equation, S = ΣWiSi/ΣWi, to calculate as a function of temperature the diffusion thermoelectricity under the influence of various competing scattering mechanisms in the metals, and by taking account of the phonon-drag contribution to the thermoelectricity. New data are presented and interpreted.

PHONON-DRAG EFFECT OF ULTRA-THIN FeSi2 AND MnSi1.7/FeSi2 FILMS

2011 ◽  
Vol 25 (22) ◽  
pp. 1829-1838 ◽  
Author(s):  
Q. R. HOU ◽  
B. F. GU ◽  
Y. B. CHEN ◽  
Y. J. HE
Keyword(s):  
Electrical Resistivity ◽  
Seebeck Coefficient ◽  
Single Crystals ◽  
Thermoelectric Power ◽  
Power Factor ◽  
Low Temperatures ◽  
Room Temperature ◽  
Phonon Drag ◽  
Drag Effect ◽  
Thermoelectric Power Factor

Phonon-drag effect usually occurs in single crystals at very low temperatures (10–200 K). Strong phonon-drag effect is observed in ultra-thin β- FeSi 2 films at around room temperature. The Seebeck coefficient of a 23 nm-thick β- FeSi 2 film can reach -1.375 mV/K at 343 K. However, the thermoelectric power factor of the film is still small, only 0.42×10-3 W/m-K2, due to its large electrical resistivity. When a 27 nm-thick MnSi 1.7 film with low electrical resistivity is grown on it, the thermoelectric power factor of the MnSi 1.7 film can reach 1.5×10-3 W/m-K2 at around room temperature. This value is larger than that of bulk MnSi 1.7 material in the same temperature range.

Low-Temperature Diffusion of Dopants in Silicon

1989 ◽  
Vol 163 ◽  
Author(s):  
P. Fahey ◽  
M. Wittmer
Keyword(s):  
Low Temperature ◽  
Transition Metal ◽  
Experimental Evidence ◽  
Point Defects ◽  
Low Temperatures ◽  
Surprising Result ◽  
Temperature Diffusion ◽  
Doped Silicon ◽  
Diffusion Enhancement ◽  
Dopant Atoms

AbstractIt has been reported that diffusion of substitutional dopant atoms in silicon occurs during the formation of transition-metal suicides at temperatures below 300°C. By observing the diffusion enhancements of buried marker layers of Sb-, Ga-, Ge-, and B-doped silicon layers, we provide solid experimental evidence that the diffusion enhancement induced by Pd2Si formation at low temperatures is due to point defects generated by the suicide reactions. Diffusion enhancement is observed at temperatures as low as 200°C. We have found the surprising result that diffusion is asymmetric: diffusion occurs preferentially towards the suiciding interface.

Electrical Resistivity of Metals at Low Temperatures

1982 ◽  
Vol 37 (12) ◽  
pp. 1333-1334
Author(s):  
H.-J. Bohn ◽  
G. Simon
Keyword(s):  
Electrical Resistivity ◽  
Experimental Work ◽  
Low Temperatures ◽  
Impurity Scattering ◽  
Transport Equations ◽  
Boltzmann Transport ◽  
Phonon Drag

AbstractFor the system of the coupled Boltzmann transport equations for electrons, phonons and impurities in metals the influence of the crosscoupling terms is investigated. It is shown that this results at low temperatures in a contribution to the electrical resistivity proportional to 1/√T. This is due to the fact that by phonon-impurity scattering the phonon-drag contribution is influenced by the presence of the impurities. A comparison with recently published experimental work is made.

Sign in / Sign up

Export Citation Format

Share Document