Development of detection and control of individual atoms in an optical lattice
Kyoto University Yoshiro Takahashi
Recently, a quantum gas microscopy(QGM) which is a technique of observing individual atoms with a single-site resolution for ultracold atoms loaded into a two-dimensional optical lattice has been developed. Owing to the high controllability, the realization of the ultimate quantum simulator is expected with the QGM. Recently, we have successfully developed the QGM for ytterbium atoms with the novel cooling method by using the narrow optical transition [1,2]. In particular, we have developed the Faraday QGM(see Figure) in which the Faraday rotation of the polarization of the probe light as a result of the dispersive interaction, instead of the fluorescence detection in conventional QGMs. In this method, we realized a rotation angle of about 10 degree for a single atom. Furthermore, quite recently, we have theoretically revealed the possibility of the non-destructive measurement of single atoms with no photon absorption by using a squeezed state of light. In addition, we plan to perform feedback operations based on the atom measurement, and have successfully irradiated the beam generated by a spatial light modulator into the atoms in the optical lattice. We also plan to develop the coherent feedback technique without the measurement towards the realization of novel non-local interaction between atoms in different lattice sites. R. Yamamoto, J. Kobayashi, T. Kuno, K. Kato and Y. Takahashi,"An ytterbium quantum gas microscope with narrow-line laser cooling", New J. Phys. 18, 023016 (2016).
 R. Yamamoto, J. Kobayashi, K. Kato, T. Kuno, Y. Sakura, and Y. Takahashi, "Site-resolved imaging of single atoms with a Faraday quantum gas microscope", arXiv:1607.07045.