Ultrafast Transient Absorption Spectroscopy, TAS, is a pump-probe spectroscopic technique which facilitates the understanding of photochemical and photophysical processes. Very short duration (femtosecond) pulses of laser light (UV to visible) is used to initiate (pump) photo-induced processes in photoactive materials. Broadband (visible to near IR) light is then used to probe the sample, allowing the relaxation and consequences of these processes to be followed. TAS facilitates development of new materials in the areas of photovoltaics, photoelectrochemistry and photocatalysis.
Capabilities include:
Probe Beam:
- 10 kHz repetition rate.
- ~170 fs pulse duration.
- Broad band radiation generated between 315 and 1600 nm.
- Linearly polarised.
- Pump-probe time delay introduced using a motorised delay stage resulting in a temporal window of ~4 nm which can be studied.
Pump Beam:
- Chopped to 5 kHz repetition rate.
- ~170 fs pulse duration.
- Fully tuneable between 315 - 1200 nm.
- Polarisation control allowing rotation of linearly polarised radiation and generation of circularly polarised radiation.
Sample Area:
- Large flexible sample area.
- Motorised sample stage allowing the sample to be rastered.
Detection:
- Transient signal detected in transmission or reflection.
- CMOS detector used for UV/Vis probe detection, InGaAs detector used for nIR probe detection.
- Spectral resolution of ≤2 nm.
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