3 papers
physics.optics2026
Terahertz-driven four-wave mixing at glass surfaces: Probing vibrational resonances and structural regimes
Mathias Hedegaard Kristensen, Jérôme Degert, Theo Guillaume +3
Disordered materials such as glasses exhibit complex structural dynamics that are challenging to probe with conventional spectroscopies. We demonstrate that terahertz-driven four-w…
physics.app-ph2025
High-Accuracy Material Classification via Reference-Free Terahertz Spectroscopy: Revisiting Spectral Referencing and Feature Selection
Mathias Hedegaard Kristensen, PaweÅ Piotr Cielecki, Esben Skovsen
We investigate how feature selection algorithms can enable accurate, reference-free classification of materials using sparse-frequency terahertz (THz) reflection spectroscopy. Thre…
physics.optics2025
Broadband Two-Dimensional Far-Field Beam Profiling of Commercial CW Terahertz Photomixers from 0.2 to 1.5 THz
Mathias Hedegaard Kristensen, Esben Skovsen
We present a systematic far-field characterization of four commercial PIN diode terahertz photomixers over the 0.2-1.5 THz frequency range using a two-dimensional (2D) raster scann…