In this seminar, I will talk about recent works realized by our group with emphasis in two topics. The first one concerns the use of light beams and photons with orbital angular momentum, for the experimental study of Quantum Thermodynamics through the investigation of fluctuation relations, namely the Jarzynki and generalized Jarzynski fluctuation relations (To appear in PRA - arXiv:1912.06447v2 [quant-ph]). The second one concerns the study of phase conjugation for structured light beams. Phase conjugation is a very interesting effect discovered in the early days of non-linear optics, which is related to the temporal eversion of the propagation of light beams. The concept initially applied to the wavefront was generalized for the polarization аnd we have studied the combined effect in vector vortex beams (ACS Photonics 2020, 7, 249−255).