News

Ursula Keller wins “Swiss Nobel” Marcel Benoist Prize- for pioneering work in ultrafast lasers

Farewell: the NCCR MUST ended - on June 30, 2022

MUST2022 Conference- a great success!

New scientific highlights- by MUST PIs Wörner, Chergui, and Richardson

FELs of Europe prize for Jeremy Rouxel- “Development or innovative use of advanced instrumentation in the field of FELs”

Ruth Signorell wins Doron prizefor pioneering contributions to the field of fundamental aerosol science

New FAST-Fellow Uwe Thumm at ETH- lectures on Topics in Femto- and Attosecond Science

International Day of Women and Girls in Science- SSPh asked female scientists about their experiences

New scientific highlight- by MUST PIs Milne, Standfuss and Schertler

EU XFEL Young Scientist Award for Camila Bacellar,beamline scientist and group leader of the Alvra endstation at SwissFEL

Prizes for Giulia Mancini and Rebeca Gomez CastilloICO/IUPAP Young Scientist Prize in Optics & Ernst Haber 2021

Nobel Prize in Chemistry awarded to RESOLV Member Benjamin List- for the development of asymmetric organocatalysis

Hans Jakob Wörner invited to give the „New Horizons Solvay Lectures” - online, October 5, 12 and 19

Unusual keynote talk at an international scientific conference- Do photons show gender bias?

NCCR MUST at Scientifica 2021- Lightning, organic solar cells, and virtual molecules

Time Resolved Surface 2nd Harmonic Generation TRSSHG (collinear configuration)

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Location		Contact
LEPA Ecole Polytechnique Fédérale de Lausanne EPFL SB ISIC LEPA CH-1015 Lausanne		Astrid Olaya Tel +41 21 693 3655 $asi4tru&idt%.oj1lad+yay&@er6pfr8l.j+chk
Configuration / Setup		Literature
Collinear configuration Frequency 1006 Hz Pulse temporal width: 45 fs Pump Wavelength: 800 nm Pump energy: 1.23 mJ (total) Probe wavelength: 235 – 2700 nm Probe energy: 1 – 190 µJ (total) depending on the wavelength Pump and probe are plane polarized. Rotating half wave plate for pump and probe. Analyzer at the output of the cell. Simultaneous SHG by the pump and the probe		Olaya A. J., Brevet P. F., Girault H. H., Polarization Angle Dependence of the Pump on the Ultrafast Excited State Dynamics of Methyl Orange. In preparation (2012)
The image shows the sample (1), a liquid/liquid interface in this case, and the pump (red arrow) and probe (green arrow) synchronized on the same mirror at the input of the cell. On the left the computer control delay of the pump (2) and the motorized rotating half wave plates the probe (3) and the pump (4). The setup allows second harmonic generation from both beams simultaneously and therefore sum frequency generation when synchronized at the interface. Pump and probe light polarization effects on the excited state dynamics can also be performed.		An optical parametric amplifier (OPerA SOLO (Light Conversion) is used to generate wavelength tunable pulses in order to probe the interface by recording SHG spectra under and without excitation. Unlike recent publications regarding time resolved SHG at liquid/liquid interfaces, in our setup the pump and the probe are directed to the interface in a collinear configuration, generating SH from both beams, and therefore generating SF when both arms are synchronized. The generation of SH by both beams allows tuning and therefore delaying either the pump or the probe depending on the required experiment. The pump is plane polarized and a rotating half wave plate allows us to study the effect of the light polarization on the dynamics of the excited states. Besides studying the whole spectrum of the molecules adsorbed at the interface under and without excitation, including light polarization effects, we can also study the behavior of the excited states dynamics under electrical polarization of the interface. Which we hope will give us valuable information regarding charge and electron transfer processes.