High-frequency phonons drive large phonon-drag thermopower in semiconductors at high carrier density
Journal Article
·
· Physical Review. B
- Boston College, Chestnut Hill, MA (United States); Boston College
- Humboldt-Universität zu Berlin (Germany)
- Indian Inst. of Science, Bangalore (India)
- Boston College, Chestnut Hill, MA (United States)
It has been well established that (i) the thermopower of semiconductors can be enhanced through a phe- nomenon known as the drag effect, and (ii) the drag enhancement involves only low-frequency acoustic phonons and benefits from low electron densities and low temperatures. Using first-principles calculations we show that large drag enhancements to the thermopower are possible at high carrier density even at room temperature and arise from high-frequency acoustic phonons. A fascinating example is cubic boron arsenide (BAs) for which the calculated room temperature drag enhancement of the thermopower exceeds an order of magnitude at a high hole density of 1021 cm–3. This remarkable behavior stems from the simultaneously weak phonon-phonon and phonon-hole scattering of the high-frequency phonons in BAs that become drag active at high carrier densities through electron-phonon interactions. Furthermore, this work advances our understanding of coupled electron-phonon nanoscale transport and introduces an unexpected paradigm for achieving large thermopowers.
- Research Organization:
- Boston College, Chestnut Hill, MA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division
- Grant/Contract Number:
- SC0021071
- OSTI ID:
- 1923498
- Journal Information:
- Physical Review. B, Journal Name: Physical Review. B Journal Issue: 8 Vol. 107; ISSN 2469-9950
- Publisher:
- American Physical Society (APS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Colossal phonon drag enhanced thermopower in lightly doped diamond
Large electron-phonon drag asymmetry and reverse heat flow in the topological semimetal θ-TaN
Effect of Phonon Drag on the Thermopower in a Parabolic Quantum Well
Journal Article
·
Wed Jun 01 20:00:00 EDT 2022
· Materials Today Physics
·
OSTI ID:1876375
Large electron-phonon drag asymmetry and reverse heat flow in the topological semimetal θ-TaN
Journal Article
·
Tue Mar 18 20:00:00 EDT 2025
· Materials Today Physics
·
OSTI ID:2537938
Effect of Phonon Drag on the Thermopower in a Parabolic Quantum Well
Journal Article
·
Tue Mar 15 00:00:00 EDT 2016
· Semiconductors
·
OSTI ID:22645603