Seebeck coefficient in correlated low-dimensional organic metals

Thermoelectric properties were simulated for low-dimensional atomistic model structures based on first-principles calculation. New methodology about the first-principles simulation on Seebeck coefficient at arbitrary temperature and carrier concentration is presented. Dependence of Seebeck coefficient on scale, temperature, and carrier concentration has been demonstrated for silicon and beta silicon carbide nanowire models. Compared with the corresponding bulk models, a significant increase of the absolute value of Seebeck coefficient can be observed owing to quantum confinement by dimensional reduction. By the simulation with considering the energy dependence of the relaxation time, the Seebeck coefficient from the viewpoint of first principles can be evaluated as a range determined by the scattering constants peculiar to particular scattering processes.

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Low Dimensional Organic Metals: Structural and Electronic Properties of Cs[Pd(dmit)2]2

NATO ASI Series - Frontiers of High-Pressure Research ◽

10.1007/978-1-4899-2480-3_4 ◽

1991 ◽

pp. 33-43 ◽

Cited By ~ 1

Author(s):

I. Marsden ◽

M. Allan ◽

R. H. Friend ◽

A. E. Underhill ◽

R. A. Clark

Keyword(s):

Electronic Properties ◽

Organic Metals ◽

Structural And Electronic Properties ◽

Low Dimensional

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Carrier Pocket Engineering for the Design of Low Dimensional Thermoelectrics with High Z3DT

MRS Proceedings ◽

10.1557/proc-626-z4.3 ◽

2000 ◽

Vol 626 ◽

Cited By ~ 2

Author(s):

Takaaki Koga ◽

Stephen B. Cronin ◽

Mildred S. Dresselhaus

Keyword(s):

Thermal Conductivity ◽

Electrical Conductivity ◽

Seebeck Coefficient ◽

Figure Of Merit ◽

Thermoelectric Figure Of Merit ◽

Engineering Model ◽

Thermoelectric Figure ◽

Model Calculations ◽

Low Dimensional ◽

Good Agreement

ABSTRACTThe concept of carrier pocket engineering applied to Si/Ge superlattices is tested experimentally. A set of strain-symmetrized Si(20Å)/Ge(20Å) superlattice samples were grown by MBE and the Seebeck coefficient S, electrical conductivity σ, and Hall coefficient were measured in the temperature range between 4K and 400K for these samples. The experimental results are in good agreement with the carrier pocket engineering model for temperatures below 300K. The thermoelectric figure of merit for the entire superlattice, Z3DT, is estimated from the measured S and σ, and using an estimated value for the thermal conductivity of the superlattice. Based on the measurements of these homogeneously doped samples and on model calculations, including the detailed scattering mechanisms of the samples, projections are made for δ-doped and modulation-doped samples [(001) oriented Si(20Å)/Ge(20Å) superlattices] to yield Z3DT ≈ 0.49 at 300K.

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