Lez #61+62 Coherent vibrational imaging II - RIKES

We described the basics of RIKES: a vibrationally resonant combination of pump and stokes can induce optical anisotropy which generates an electric field along a direction orthogonal to the incoming stokes, via a four wave mixing process. This effect can be homodyne detected, or via balanced detection, to measure separately the real and imaginary parts of the non linear susceptibility.

Lez #57+58 Coherent vibrational imaging I

 We introduced the basic principles of linear and non linear imaging, with or without vibrational sensitivity. We then discussed the basics of CARS imaging, the nor resonant background issues and how to resolve them.

Lez #59+60 Coherent vibrational imaging I - SRS/CARS non resonant background

 We introduced the basic principles of linear and non linear imaging, with or without vibrational sensitivity. We then discussed the basics of CARS imaging, the nor resonant background issues and how to resolve them.

Lez #55+56 Time-Domain Impulsive Vibrational Spectroscopy

 We discussed the Impulsive Vibrational Scattering technique, in which a pair of temporally separated pulses is used to map vibrational excitations in the time domain. The experimental setup follows a pump-probe scheme, where an ultrashort broadband pump pulse generates vibrational coherences via two interactions with spectral components shifted by one vibrational quantum. The coherences modulate the optical properties of the medium, which are then monitored by a delayed probe. We derived the analytical expressions using the diagrammatic formalism, assuming impulsive beams. On classroom some lecture notes.

Lez #53+54 Dephasing

 We discussed from a microscopic point of view how out-of-diagonal elements of the density matrix are damped due to the interaction with the environment. As a reference, you can use chapter 5 of the “Principles of Nonlinear Optical  Spectroscopy: A Practical Approach” by P. Hamm

Lez #51+52 Esercitazione 2

 Seconda parte della risoluzione del secondo esonero 2022. Risposta HL1 in condizioni di risonanza e fuori risonanza. Risposta di HL2. Interpretazione fisica dei risultati e confronto con la risposta RRS1.

Lez #49+50 Esercitazione 1

Prima parte della risoluzione del secondo esonero 2022. Diagrammi di Hot Luminescence (HL1 e HL2). Calcolo esplicito di HL1.