Alexis and his research group develop multidimensional non-linear optical spectroscopy techniques to be applied in harsh measurement environments such as turbulent flows, flames, and plasmas. They build advanced laser diagnostics that involves state-of-the-art coherent imaging spectrometers and the utilization of ultrafast amplifier systems which produce intense high-peak power laser pulses on a femtosecond- and picosecond timescale. These optical instruments allows for in-situ determination of scalars (e.g. temperature and mixture composition) with space-time resolution, which is important to reveal new insight into the underlying mechanisms that can help to make propulsion systems or other combustion processes more “green” and sustainable. Their most recent invention concern an ability to perform spectroscopic broadband interrogation and detection of coherent Raman scattering in the wide-field mode.
Scientific Interest:
- Laser diagnostics
- Energy and Combustion Science Applications
Expertise:
- Coherent anti-Stokes Raman scattering
- Coherent imaging
- Non-linear optical spectroscopy
Models and equipment:
- Numerical code to perform four-wave-mixing time-dependent density matrix calculations
- Polarisation-sensitive wide-field coherent imaging spectrometer with ~3000 lines/mm dispersion
- Ti:Sapphire femtosecond regenerative amplifier system, 35 femtosecond, 7.5 mJ @ 1 kHz
- Second harmonic bandwidth compressor, ~6-10 picosecond, 1.5 mJ @ 1 kHz
- Front-illuminated sCMOS Camera, 16-bit with ~200 rows read out @ 1 kHz