Heat dissipation in quasi-ballistic single-atom contacts at room temperature

AbstractWe report on evaluations of local heating in Au single-atom chains at room temperature. We performed onsite thermometry of atomic-scale Au junctions under applied sinusoidal voltage of variable amplitudes. The AC approach enabled to preclude electromigration effects for characterizing the influence of energy dissipations on the lifetime. We elucidated nonlinear increase in the effective temperature of the current-carrying single-atom chains with the voltage amplitudes, which was attributed to subtle interplay between electron-phonon scattering and electron-mediated thermal transport in the quasi-ballistic conductor. We also found that only 0.2% of the electric power contributed to local heating while the majority was consumed at the diffusive bank. The present findings can be used for thermal management of future integrated nanoelectronics.

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Prediction of higher thermoelectric performance in BiOCuSe by weakening electron-polar optical phonon scattering

10.21203/rs.3.rs-37817/v1 ◽

2020 ◽

Author(s):

Tianqi Zhao ◽

Quinn Gibson ◽

Luke Daniels ◽

Ben Slater ◽

Furio Cora

Keyword(s):

Carrier Mobility ◽

Figure Of Merit ◽

Room Temperature ◽

Phonon Scattering ◽

Hole Mobility ◽

Polar Optical Phonon ◽

First Principles Calculations ◽

Thermoelectric Figure ◽

Optical Phonon Scattering ◽

Electron Phonon Scattering

Abstract BiOCuSe is a promising thermoelectric material, but its applications are hindered by low carrier mobility. We use first principles calculations to analyse electron-phonon scattering mechanisms and evaluate their contributions to the thermoelectric figure of merit ZT. The combined scattering of carriers by polar optical (PO) and longitudinal acoustic (LA) phonons yields an intrinsic hole mobility of 32 cm2 V-1 s-1 at room temperature and a temperature power law of T-1.5, which agree well with experiments. We demonstrate that electron phonon scattering in the Cu-Se layer dominates at low T, while contributions from the Bi-O layer become increasingly significant at higher T. At room temperature, ZT is calculated to be 0.48 and can be improved by 30% through weakening PO phonon scattering in the Cu-Se layer. This finding agrees with the experimental observation that weakening the carrier-phonon interaction by Te substitution in the Cu-Se layer improves mobility and ZT. At high T, the figure of merit is improved by weakening phonon scattering in the Bi-O layer instead. The theoretical ZT limit of BiOCuSe is calculated to be 2.5 at 875 K.

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Effects of uniaxial tensile strain on the electron–phonon scattering limited carrier mobility in an n-type monolayer MoS2 at room temperature: first-principles calculations

Journal of Physics Condensed Matter ◽

10.1088/1361-648x/ab161f ◽

2019 ◽

Vol 31 (29) ◽

pp. 295502

Author(s):

Fei Guo ◽

Zhe Liu ◽

Mingfeng Zhu ◽

Yisong Zheng

Keyword(s):

First Principles ◽

Carrier Mobility ◽

Tensile Strain ◽

Room Temperature ◽

Phonon Scattering ◽

Uniaxial Tensile ◽

First Principles Calculations ◽

Monolayer Mos2 ◽

Electron Phonon Scattering

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Ultrafast dynamics of the Itinerant Antiferromagnet UNiGa5

MRS Proceedings ◽

10.1557/proc-0893-jj05-08 ◽

2005 ◽

Vol 893 ◽

Author(s):

Ee Min Elbert Chia ◽

H. J. Lee ◽

Namjung Hur ◽

E. D. Bauer ◽

T. Durakiewicz ◽

...

Keyword(s):

Relaxation Time ◽

Heavy Fermion ◽

Room Temperature ◽

Phonon Scattering ◽

Ultrafast Dynamics ◽

Spin Gap ◽

Time Resolved ◽

Amplitude Increase ◽

Reflectivity Data ◽

Electron Phonon Scattering

AbstractTime-resolved photoinduced reflectivity data were measured for the itinerant antiferromagnet UNiGa5 (TN ≈ 85 K) from room temperature down to 10 K. The relaxation time τ increases sharply near TN, which we attribute to the opening of a spin gap. In addition, at the lowest temperatures τ increases with a T1 dependence, which is similar to that shown by the heavy fermion YbAgCu4, but with no blocking of electron-phonon scattering within the DOS peak. The transient amplitude increase at TN with a temperature dependence that is consistent with the appearance of a spin gap.

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Electron–phonon scattering limited hole mobility at room temperature in a MoS2 monolayer: first-principles calculations

Physical Chemistry Chemical Physics ◽

10.1039/c9cp04418c ◽

2019 ◽

Vol 21 (41) ◽

pp. 22879-22887 ◽

Cited By ~ 8

Author(s):

Fei Guo ◽

Zhe Liu ◽

Mingfeng Zhu ◽

Yisong Zheng

Keyword(s):

Room Temperature ◽

Phonon Scattering ◽

Hole Mobility ◽

Interaction Matrix ◽

First Principles Calculations ◽

Phonon Interaction ◽

Electron Phonon Interaction ◽

Mos2 Monolayer ◽

Intervalley Scattering ◽

Electron Phonon Scattering

Electron–phonon interaction matrix elements show that (a) valence band holes have stronger intervalley scattering than (b) conduction band electrons.

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EFFECT OF INELASTIC SCATTERING OF HOT ELECTRONS ON THERMIONIC COOLING IN A SINGLE-BARRIER STRUCTURE

International Journal of Modern Physics B ◽

10.1142/s0217979200001503 ◽

2000 ◽

Vol 14 (14) ◽

pp. 1451-1457

Author(s):

C. ZHANG

Keyword(s):

Inelastic Scattering ◽

Room Temperature ◽

Phonon Scattering ◽

Hot Electrons ◽

Electron Interaction ◽

Barrier Structure ◽

Phonon Interaction ◽

Electron Phonon Interaction ◽

Barrier Region ◽

Electron Phonon Scattering

One of the important problems in thermionics using layered structures is the inelastic scattering of hot electrons in the electrodes and in the barrier region. Scattering in these systems is mainly via the electron–phonon interaction, or indirectly via the electron–electron interaction. In semiconductor heterostructures at room temperature, the LO-phonon plays a crucial role in thermalising electrons. In this work we study the effect of electron–phonon scattering on thermionic cooling in a single-barrier structure. Because of the asymmetry of the barrier under a bias, a larger fraction of the total energy loss will be dissipated in the hot electrode. As a result, we find that the theoretical thermal efficiency can increase due to limited electron–phonon scattering.

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INFLUENCE OF THE ANISOTROPY OF ELECTRON-PHONON SCATTERING ON THE LOW TEMPERATURE RESISTIVITY OF NORMAL METALS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19786465 ◽

1978 ◽

Vol 39 (C6) ◽

pp. C6-1052-C6-1053

Author(s):

R. Krsnik ◽

E. Babić

Keyword(s):

Low Temperature ◽

Phonon Scattering ◽

Normal Metals ◽

Temperature Resistivity ◽

Electron Phonon Scattering

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TEMPERATURE DEPENDENCE BEHAVIOR OF ELECTRICAL RESISTIVITY IN NOBLE METALS AT LOW TEMPERATURES

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v5i3.1887 ◽

2014 ◽

Vol 5 (3) ◽

pp. 982-992 ◽

Cited By ~ 1

Author(s):

M AL-Jalali

Keyword(s):

Experimental Data ◽

Electrical Resistivity ◽

Temperature Dependence ◽

Concentration Dependence ◽

Low Temperatures ◽

Noble Metals ◽

Phonon Scattering ◽

Theoretical Models ◽

Residual Resistivity ◽

Electron Phonon Scattering

Resistivity temperature â€“ dependence and residual resistivity concentration-dependence in pure noble metals(Cu, Ag, Au) have been studied at low temperatures. Dominations of electron â€“ dislocation and impurity, electron-electron, and electron-phonon scattering were analyzed, contribution of these mechanisms to resistivity were discussed, taking into consideration existing theoretical models and available experimental data, where some new results and ideas were investigated.

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