Two-dimensional atom localization via phase-sensitive absorption-gain spectra in five-level hyper inverted-Y atomic systems

A scheme for realizing two-dimensional atom localization in the sub-wavelength domain is proposed in a microwave- driven five-level hyper inverted-Y atomic system in which the atom interacts with a weak probe field, two control fields together with two orthogonal standing-wave fields. Because of the spatially dependent atom-field interaction, the information about the position of the atom can be extracted directly from the absorption and gain spectra of a weak probe field. It has been found that the probe detuning, the intensities of two control fields, and the relative phase of the driving fields can significantly improve the localization precision. Moreover, the maximal probability of finding the atom at an expected position in the sub-wavelength domain of the standing-wave field can reach unity via properly adjusting the system parameters. (C) 2015 Optical Society of America