Dynamics of matter waves undergoing Bloch oscillations in a ring cavity

Lucas Borges

Published Mar 10, 2021• 0 citations

Abstract

The work developed in this thesis investigate the dynamics of ultracold atoms trapped in a ring cavity and undergoing Bloch oscillations due to the influence of a one-dimensional vertical optical lattice and of the gravitational force.In this configuration, the atoms collectively scatter light from the pump into the copropagating cavity mode, which then leads to a self-consistent grating of the matter: this mechanism was coined collective atomic recoil lasing (CARL).Such interaction between atomic motion and cavity modes provides a possible continuous and non-destructive method to monitor the Bloch oscillations dynamics, which could be implemented in atomic gravimeters.This dissertation investigates the fundamental problem of dissipation effects due to spontaneous emission of the atoms, which is responsible for a suppression of the Bloch oscillations signatures on the light modes.We also study a possible solution for this issue by including a third atomic level in the configuration to explore a probable dissipation reduction due to the phenomenon of electromagnetically induced transparency (EIT).

DOI: 10.11606/d.76.2021.tde-03092021-113103

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