| Autor: |
Sahu, Subhranshu Sekhar, Sahoo, Bijoy Kumar |
| Předmět: |
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| Zdroj: |
AIP Conference Proceedings; 2020, Vol. 2220 Issue 1, p130013-1-130013-4, 4p, 1 Graph |
| Abstrakt: |
Higher thermoelectric (TE) efficiency of AlxIn1-xN /GaN heterostructure (HS) demands low thermal conductivity (k) and high power factor. A smaller k would increase figure of merit (ZT) further. The internal polarization electric (PE) field of AlxIn1-xN /GaN HS enhances Seebeck coefficient (S) and electrical conductivity (σ) of this HS; however action of PE field on k has not been investigated. In this report, PE field effect on k of AlxIn1-xN /GaN HS has been explored theoretically. The PE field modifies k of AlxIn1-xN alloy. Investigation of thermal conductivities k and kp (k: without PE and kp: including PE) as a function of temperature predicts pyroelectric behavior of HS. Thermal conductivities k and kp show crossover at a temperature Tp. Below Tp, kpp, kp>k.kp is considerably contributed from PE field due to +ve thermal expansion. ZT is enhanced below Tp, whereas ZT is decreased above Tp. It is found that Tp depends on Al composition x and strain due to interfaces and can be elevated above room temperature by choosing of x. Thus, k of the HS can be modified according to requirement by tailoring the Al composition; making it suitable simultaneously for design of high temperature pyroelectric sensors and TE device for maximum power generation. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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