We present the dynamics of an electron constrained over an 1D ring with radius of0.142 nm driven by a laser field. The temporal evolution of the system is evaluatedby a semi-analytical solution of the full quantum time dependent Schr¨odinger equation.In our calculation the gap energy between the ground and the first excited state ofthe nanoring is three times the photon energy laser (0.63 eV) and the laser intensity is4·1014 W/cm2. Our analysis is performed by considering different polarization states ofthe incident laser. Our attention is mainly focused on the study of the High HarmonicGeneration (HHG), the energy and the angular momentum absorbed by the drivensystem. We observe 1) that the harmonic yield is strongly dependent upon the pumppolarization field and almost vanishes for circular polarization and 2) that the ring canbe left in a state with average angular momentum different than zero. In figure weshow the time average of the absorbed angular momentum (in atomic units) versuspolarization angle (θ = 0◦ and θ = 90◦correspond to linear polarization along x and yaxes respectively; θ = 45◦corresponds to circular polarization).
|Numero di pagine||1|
|Stato di pubblicazione||Published - 2013|