Shot-Noise Limited FSRM

• Applicant: Professor Dr. Peter Gilch
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2008 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 73582064

Raman microscopy is an established imaging technique with applications in biology, medicine and material science. Taking profit from the good correlation between Raman signatures and molecular structures it enables label-free imaging. As Raman signals are commonly weak, huge efforts are presently undertaken to enhance them via non-linear effects. A couple of years ago we have demonstrated that femtosecond stimulated Raman scattering is suitable for this purpose. Contrary to some other approaches, the technique, femtosecond stimulated Raman microscopy (FSRM), yields complete Raman spectra simultaneously. In the preceding funding period we have constructed a dedicated laser light source for FSRM. The source is suitable for biological samples. Presently, the signal quality is limited by the multi-channel detector. With this funding period we intend to come up with a detector operating at or close to the physical limit concerning the noise properties, i.e. we intend to reach the shot-noise limit. To this end, we will collaborate with a specialist in the field of optical detectors, Dr. Roger Light (University of Nottingham). Since the ultimate goal is high quality imaging of bio-samples, we lay the foundation on that by investigating plant tissues. For these samples benchmark results using conventional Raman microscopy exist.

• DFG Programme: Research Grants