scholarly journals Contribution of D-Band Electrons to Ballistic Electron Transport and Interfacial Scattering During Electron-Phonon Nonequilibrium in Thin Metal Films

2009 ◽  
Author(s):  
Patrick E. Hopkins
Keyword(s):  
Thin Films ◽  
Energy Transfer ◽  
Electron Transport ◽  
Conduction Band ◽  
Metal Films ◽  
Electronic Excitations ◽  
Thin Metal Films ◽  
Ballistic Electron ◽  
Ballistic Electron Transport ◽  
Interface Scattering

Electron-interface scattering during electron-phonon nonequilibrium in thin films creates another pathway for electron system energy loss as characteristic lengths of thin films continue to decrease. As power densities in nanodevices increase, excitations of electrons from sub-conduction-band energy levels will become more probable. These sub-conduction-band electronic excitations significantly affect the material’s thermophysical properties. In this work, the effects of d-band electronic excitations are considered in electron energy transfer processes in thin metal films. In thin films with thicknesses less than the electron mean free path, ballistic electron transport leads to electron-interface scattering. The ballistic component of electron transport, leading to electron-interface scattering, is studied by a ballistic-diffusive approximation of the Boltzmann Transport Equation. The effects of d-band excitations on electron-interface energy transfer is analyzed during electron-phonon nonequilibrium after short pulsed laser heating in thin films.

Contribution of Ballistic Electron Transport to Energy Transfer During Electron-Phonon Nonequilibrium in Thin Metal Films

2009 ◽  
Vol 131 (4) ◽  
Author(s):  
Patrick E. Hopkins ◽  
Pamela M. Norris
Keyword(s):  
Thin Films ◽  
Electron Transport ◽  
Phonon Scattering ◽  
High Energy ◽  
Boltzmann Transport ◽  
Phonon Coupling ◽  
Ballistic Electron ◽  
Ballistic Electron Transport ◽  
Interface Scattering ◽  
Electron Phonon Coupling

With the ever decreasing characteristic lengths of nanomaterials, nonequilibrium electron-phonon scattering can be affected by additional scattering processes at the interface of two materials. Electron-interface scattering would lead to another path of energy flow for the high-energy electrons other than electron-phonon coupling in a single material. Traditionally, electron-phonon coupling in transport is analyzed with a diffusion (Fourier) based model, such as the two temperature model (TTM). However, in thin films with thicknesses less than the electron mean free path, ballistic electron transport could lead to electron-interface scattering, which is not taken into account in the TTM. The ballistic component of electron transport, leading to electron-interface scattering during ultrashort pulsed laser heating, is studied here by a ballistic-diffusive approximation of the Boltzmann transport equation. The results for electron-phonon equilibration times are compared with calculations with TTM based approximations and experimental data on Au thin films.

The features of ballistic electron transport in a suspended quantum point contact

2014 ◽  
Vol 104 (20) ◽  
pp. 203102 ◽  
Author(s):  
A. A. Shevyrin ◽  
A. G. Pogosov ◽  
M. V. Budantsev ◽  
A. K. Bakarov ◽  
A. I. Toropov ◽  
...  
Keyword(s):  
Electron Transport ◽  
Point Contact ◽  
Quantum Point Contact ◽  
Ballistic Electron ◽  
Ballistic Electron Transport ◽  
Quantum Point

High-efficiency two-frequency laser generation in three-barrier nanostructures with ballistic electron transport

2016 ◽  
Vol 42 (9) ◽  
pp. 970-972 ◽  
Author(s):  
A. A. Borisov ◽  
S. S. Zyrin ◽  
A. A. Makovetskaya ◽  
V. I. Novoselets ◽  
A. B. Pashkovskii ◽  
...  
Keyword(s):  
Electron Transport ◽  
High Efficiency ◽  
Laser Generation ◽  
Ballistic Electron ◽  
Ballistic Electron Transport ◽  
Frequency Laser

Ballistic electron transport in InP observed by subpicosend time-resolved Raman spectroscopy

1999 ◽  
Author(s):  
Kong-Thon F. Tsen ◽  
David K. Ferry ◽  
Jyh-Shyang Wang ◽  
Chao-Hsiung Huang ◽  
Hao-Hsiung Lin
Keyword(s):  
Raman Spectroscopy ◽  
Electron Transport ◽  
Time Resolved ◽  
Ballistic Electron ◽  
Ballistic Electron Transport

Ballistic Electron Transport in AlAs Quantum Wells

2004 ◽  
Vol 93 (24) ◽  
Author(s):  
O. Gunawan ◽  
Y. P. Shkolnikov ◽  
E. P. De Poortere ◽  
E. Tutuc ◽  
M. Shayegan
Keyword(s):  
Electron Transport ◽  
Quantum Wells ◽  
Ballistic Electron ◽  
Ballistic Electron Transport

Ballistic electron transport in structured suspended semiconductor membranes

2013 ◽  
Author(s):  
A. G. Pogosov ◽  
M. V. Budantsev ◽  
E. Yu. Zhdanov ◽  
D. A. Pokhabov
Keyword(s):  
Electron Transport ◽  
Ballistic Electron ◽  
Ballistic Electron Transport

COMPARISON OF TRANSIENT BALLISTIC ELECTRON TRANSPORT IN BULK WURTZITE PHASE 6H-SiC and GaN

2008 ◽  
Vol 22 (30) ◽  
pp. 5289-5297 ◽  
Author(s):  
H. ARABSHAHI
Keyword(s):  
Conduction Band ◽  
Drift Velocity ◽  
Velocity Ratio ◽  
Ballistic Transport ◽  
Energy Separation ◽  
Wurtzite Phase ◽  
Velocity Overshoot ◽  
Ballistic Electron ◽  
Ballistic Electron Transport ◽  
Transient Velocity

An ensemble Monte Carlo simulation is used to compare bulk electron ballistic transport in 6H - SiC and GaN materials. Electronic states within the conduction band valleys at Γ1, U, M, Γ3, and K are represented by nonparabolic ellipsoidal valleys centered on important symmetry points of the Brillouin zone. The large optical phonon energy (~120 meV) and the large intervalley energy separation between the Γ and satellite conduction band valleys suggest an increasing role for ballistic electron effects in 6H - SiC , especially when compared with most III-V semiconductors such as GaAs . Transient velocity overshoot has been simulated, with the sudden application of fields up to ~5×107 Vm -1, appropriate to the gate-drain fields expected within an operational field effect transistor. A peak-saturation drift velocity ratio of 2:1 is predicted for 6H - SiC material while that for GaN is 4:1. The electron drift velocity relaxes to the saturation value of ~2×105 ms -1 within 3 ps, for both crystal structures. The transient velocity overshoot characteristics are in fair agreement with other recent calculations.

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