IR-vis sum frequency generation
07 Dec 2016



A powerful probe of interface molecules





Infrared-visible sum frequency generation (IR-Vis SFG) is a surface selective vibrational spectroscopy. As such, it is a powerful probe of the structure, interactions and chemistry of interface molecules between all phases - solid, liquid or air and can be usefully applied to a wide range of problems in fields such as catalysis, structural chemistry or photovoltaic device research.  

IR-Vis SFG spectroscopy is under continuous development at the Ultra facility.1 Currently on offer is a dedicated spectrometer, with built-in flexibility for different optical configurations (e.g. normal reflection or ATR) and different sample-types. The spectrometer uses as standard broad bandwidth IR pulses (> 400 cm-1, 50 fs) and etalon narrowed time-asymmetric  1-2 ps 800 nm pulses (giving non-resonant background suppression).

There are many interesting directions in which to develop the IR-Vis SFG technique – imaging, time resolved (ms-s and ultrafast) and two dimensional infrared. The 20W 10 kHz Ti:Sapphire laser system driving the experiment allows multiple OPAs to be driven for even broader IR bandwidths and an IR pulse shaper is available for spectral filtering and temporal shaping. Discuss your requirements with Paul Donaldson (link).

1) Donaldson et al, 2014-15, Central Laser Facility Annual Report​​​

Contact: Towrie, Mike (STFC,RAL,CLF)