Strongly confined atomic localization by Rydberg coherent population trapping

We investigate the possibility to attain strongly confined atomic localization using interacting Rydberg atoms in a coherent population trapping ladder configuration, where a standing-wave is used as a coupling field in the second leg of the ladder. Depending on the degree of compensation for the Rydberg level energy shift induced by the van der Waals interaction, by the coupling field detuning, we distinguish between two antiblockade regimes, i.e., a partial antiblockade (PA) and a full antiblockade. While a periodic pattern of tightly localized regions can be achieved for both regimes, the PA allows much faster convergence of spatial confinement, yielding a high-resolution Rydberg state-selective superlocalization regime for higher-lying Rydberg levels. In comparison, for lower-lying Rydberg levels, the PA leads to an anomalous change of spectra linewidth, confirming the importance of using a stable uppermost state to achieve a superlocalization regime.