41 citations · 165 across the 10 of their papers we have counts for
11 papers
A Unified Framework for Lifted Training and Inversion Approaches
Xiaoyu Wang, Alexandra Valavanis, Azhir Mahmood +3
The training of deep neural networks predominantly relies on a combination of gradient-based optimisation and back-propagation for the computation of the gradient. While incredibly…
Improving terahertz-detection sensitivity of 8x8 FET arrays through liquid-nitrogen cooling in a compact low-noise cryostat
Jakob Holstein, Nicholas K. North, Arne Hof +10
We show that the sensitivity of antenna-coupled field-effect transistors (FETs) to terahertz (THz) radiation improves continuously with decreasing temperature. The noise-equivalent…
Detectorless 3D terahertz imaging: achieving subwavelength resolution with reflectance confocal interferometric microscopy
Jorge Silva, Martin Plöschner, Karl Bertling +18
Terahertz imaging holds great potential for non-destructive material inspection, but practical implementation has been limited by resolution constraints. In this study, we present…
8x8 Patch-Antenna-Coupled TeraFET Detector Array for Terahertz Quantum-Cascade-Laser Applications
Jakob Holstein, Nicholas K. North, Michael D. Horbury +10
Monolithically integrated, antenna-coupled field-effect transistors (TeraFETs) are rapid and sensitive detectors for the terahertz range (0.3-10~THz) that can operate at room tempe…
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…