Ultracold atoms

Wave properties of neutral atoms naturally emerge as they are cooled down to temperatures close to the absolute zero. In this regime, their dynamics is governed by single-particle quantum effects such as the tunnel effect as well as by many-particle quantum effects such as interactions and entanglement. We investigate, from a theoretical point of view, the dynamics of ultracold atoms, matter-wave solitons, and Bose-Einstein condensates trapped in optical potentials with a special focus on designing protocols for an efficient and robust transport of ultracold atoms to be used in matter wave interferometry and atomtronic devices.

Laser-matter interaction

A three-level atom interacting with two laser fields is the scenario of a rich variety of phenomena, such as Electromagnetically Induced Transparency, Coherent Population Trapping, and Stimulated Raman Adiabatic Passage, all of them based on quantum interferences between the different absorption light paths. We theoretically investigate the potential applications of these techniques in very different fields that range from quantum information, where we study for instance novel implementations of quantum memories or new protocols for single-site addressing in optical lattices, to nanoscale microscopy.

Photonic simulators

The Helmholtz equation for the spatial evolution of the electric field amplitude of a light beam propagating along an optical waveguide resembles the temporal dynamics of a trapped quantum particle governed by the Schrödinger equation. Even more, the dynamics of the TE modes propagating along two coupled waveguides can be mapped into the dynamics of a single quantum particle in a double-well potential, with the evanescent field of the waveguides' system playing the role of quantum tunneling. In this context, we investigate the possibility to apply quantum engineering protocols, e.g., spatial adiabatic passage and SUSY quantum techniques, to systems of coupled optical waveguides with the ultimate goal of designing new optical devices with improved performances with respect to standard ones as well as for using these new devices as photonic quantum simulators.

Conical Refraction

Conical refraction is observed when a light beam passing along one of the optic axis of a biaxial crystal is transformed into a light ring. Since its discovery in the 1830s by Hamilton and Lloyd till very recently, conical refraction has been an almost forgotten phenomenon. We focus our investigations in conical refraction not only with respect to fundamental issues but also to applications such as in free space optical communications, in polarization metrology, in the manipulation of microparticles via photophoresis, and in trapping single-atoms and Bose–Einstein condensates in ring potentials.

Other topics

 We also perform investigations on the following topics: 

  • Quantum mechanics with de Broglie-Bohm quantum trajectories
  • Laser-matter interaction with high-intensity fields



Campus d'excel·lència internacional U A B