Abstract
We present a multiscale model that simulates optically induced spin currents in metallic bilayer structures that emit terahertz radiation after optical pulse excitation. We describe hot-electron transport in a metallic bilayer by a Boltzmann transport equation, which is solved numerically by a particle-in-cell approach. Optical excitation and propagation effects are taken into account by our determining the emitted terahertz waves from the excited-carrier dynamics. We apply this approach to an Fe/Pt bilayer and show in detail how microscopic scattering effects and transport determine the emitted signal. The versatility of the approach presented here allows it to be readily adapted to a wide spectrum of spintronic-terahertz-emitter designs. As an example, we show how the terahertz generation efficiency, defined as the output-power-to-input-power ratio, can be increased and optimized with use of serially stacked layers in conjunction with terahertz antireflective coatings. We derive an analytical expression for the terahertz emission of a single layer that allows us to determine the relationship between the emitted field and the current profile that generates it.
| Original language | English (US) |
|---|---|
| Article number | 054083 |
| Journal | Physical Review Applied |
| Volume | 11 |
| Issue number | 5 |
| DOIs | |
| State | Published - May 30 2019 |
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ASJC Scopus subject areas
- Physics and Astronomy(all)
Cite this
Simulation of Hot-Carrier Dynamics and Terahertz Emission in Laser-Excited Metallic Bilayers. / Nenno, Dennis M.; Binder, Rudolf; Schneider, Hans Christian.
In: Physical Review Applied, Vol. 11, No. 5, 054083, 30.05.2019.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Simulation of Hot-Carrier Dynamics and Terahertz Emission in Laser-Excited Metallic Bilayers
AU - Nenno, Dennis M.
AU - Binder, Rudolf
AU - Schneider, Hans Christian
PY - 2019/5/30
Y1 - 2019/5/30
N2 - We present a multiscale model that simulates optically induced spin currents in metallic bilayer structures that emit terahertz radiation after optical pulse excitation. We describe hot-electron transport in a metallic bilayer by a Boltzmann transport equation, which is solved numerically by a particle-in-cell approach. Optical excitation and propagation effects are taken into account by our determining the emitted terahertz waves from the excited-carrier dynamics. We apply this approach to an Fe/Pt bilayer and show in detail how microscopic scattering effects and transport determine the emitted signal. The versatility of the approach presented here allows it to be readily adapted to a wide spectrum of spintronic-terahertz-emitter designs. As an example, we show how the terahertz generation efficiency, defined as the output-power-to-input-power ratio, can be increased and optimized with use of serially stacked layers in conjunction with terahertz antireflective coatings. We derive an analytical expression for the terahertz emission of a single layer that allows us to determine the relationship between the emitted field and the current profile that generates it.
AB - We present a multiscale model that simulates optically induced spin currents in metallic bilayer structures that emit terahertz radiation after optical pulse excitation. We describe hot-electron transport in a metallic bilayer by a Boltzmann transport equation, which is solved numerically by a particle-in-cell approach. Optical excitation and propagation effects are taken into account by our determining the emitted terahertz waves from the excited-carrier dynamics. We apply this approach to an Fe/Pt bilayer and show in detail how microscopic scattering effects and transport determine the emitted signal. The versatility of the approach presented here allows it to be readily adapted to a wide spectrum of spintronic-terahertz-emitter designs. As an example, we show how the terahertz generation efficiency, defined as the output-power-to-input-power ratio, can be increased and optimized with use of serially stacked layers in conjunction with terahertz antireflective coatings. We derive an analytical expression for the terahertz emission of a single layer that allows us to determine the relationship between the emitted field and the current profile that generates it.
UR - http://www.scopus.com/inward/record.url?scp=85066752060&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85066752060&partnerID=8YFLogxK
U2 - 10.1103/PhysRevApplied.11.054083
DO - 10.1103/PhysRevApplied.11.054083
M3 - Article
AN - SCOPUS:85066752060
VL - 11
JO - Physical Review Applied
JF - Physical Review Applied
SN - 2331-7019
IS - 5
M1 - 054083
ER -