41 citations · 165 across the 10 of their papers we have counts for
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Terahertz quantum cascade lasers with thin resonant-phonon depopulation active regions and surface-plasmon waveguides
M. Salih, P. Dean, A. Valavanis +5
We report three-well, resonant-phonon depopulation terahertz quantum cascade lasers with semi-insulating surface-plasmon waveguides and reduced active region (AR) thicknesses. Devi…
Optical absorption in highly-strained Ge/SiGe quantum wells: the role of Γ-to-Δ scattering
L. Lever, Z. Ikonić, A. Valavanis +7
We report the observation of the quantum-confined Stark effect in Ge/SiGe multiple quantum well heterostructures grown on Si(0.22)Ge(0.78) virtual substrates. The large compressive…
An extended density matrix model applied to silicon-based terahertz quantum cascade lasers
T. V. Dinh, A. Valavanis, L. J. M. Lever +2
Silicon-based terahertz quantum cascade lasers (QCLs) offer potential advantages over existing III-V devices. Although coherent electron transport effects are known to be important…
Material configurations for n-type silicon-based terahertz quantum cascade lasers
A. Valavanis, T. V. Dinh, L. J. M. Lever +2
Silicon-based quantum cascade lasers (QCLs) offer the prospect of integrating coherent THz radiation sources with silicon microelectronics. Theoretical studies have proposed a vari…
Theory and design of quantum cascade lasers in (111) n-type Si/SiGe
A. Valavanis, L. Lever, C. A. Evans +2
Although most work toward the realization of group IV quantum cascade lasers (QCLs) has focused on valence-band transitions, there are many desirable properties associated with the…
Intersubband carrier scattering in n- and p-Si/SiGe quantum wells with diffuse interfaces
A. Valavanis, Z. Ikonić, R. W. Kelsall
Scattering rate calculations in two-dimensional Si/SiGe systems have typically been restricted to rectangular Ge profiles at interfaces between layers. Real interfaces, however, ma…