Enginyeria de sistemes de tres nivells mitjançant passatge adiabàtic

Laburpena

This Thesis aims to contribute to the field of Quantum Optics Engineering with applications based mainly on the Stimulated Raman Adiabatic Passage (STIRAP) technique. The STIRAP technique consists of an efficient population transfer between two atomic states coupled to an intermediate state by adiabatically following one of the eigenstates of the Hamiltonian, the dark state. First, we present a proposal to implement nanoscale resolution microscopy using the sub-wavelength localisation adiabatic passage technique. Second, a new type of atomic-frequency-comb quantum memory via the piecewise adiabatic passage technique has been investigated, which offers potential advantages over the state-of-the-art ones. We have also explored the possibility to implement adiabatic passage beyond the optical range, through the participation in the first experimental attempt to demonstrate STIRAP in the XUV/x-ray regime. In addition, we have provided a general theoretical framework to study the feasibility to perform spatial adiabatic passage, the spatial analogue of STIRAP, for a Bose-Einstein condensate in a triple-well potential. Last, we have studied the conditions for achieving lasing without inversion in a particular four-level atomic scheme using the quantum-jump approach, obtaining a deeper understanding of the involved physical mechanisms.