By using pumping that realizes double electromagnetically induced transparency for the D1 line of Rubidium, we show that a giant nonlinear interaction between two optical beams propagating through a Rubidium gas can be achieved.
We investigate the Kerr and magneto-optical effects for a probe laser field with two orthogonally polarized components, propagating in a cold Rydberg atomic gas with an inverted-Y-type level configuration via double electromagnetically induced transparency (EIT). Through an approach beyond both mean-field and ground-state approximations, we make detailed calculations on third-order nonlinear optical susceptibilities and show that the system possesses giant nonlocal self- and cross-Kerr nonlinearities contributed by Rydberg-Rydberg interaction. The theoretical result of the cross-Kerr nonlinearity obtained for 85Rb atomic gas is very close to the experimental one reported recently. Moreover, we demonstrate that the probe laser field can acquire a very large magneto-optical rotation via the double EIT, which may be used to design atomic magnetometers with high precision. The results presented here are promising not only for the development of nonlocal nonlinear magneto-optics but also for applications in precision measurement and optical information processing and transmission based on Rydberg atomic gases.
Strong optical nonlinearities are key to a range of optical technologies, in particular, to the generation of quantum light states. This paper proposes and demonstrates a novel nonlinear mechanism based on an N-level electro-magnetic induced transparency (EIT) in a warm rubidium vapor. Our scheme relies on using an optical frequency comb as a pump and a CW probe signal, which co-propagate and interact in warm rubidium vapor, as shown in Fig. 1(a). Multiple comb lines excite N-level EIT resonances as shown in Fig. 1(b), which modifies the optical response of the medium, creating a giant Kerr nonlinearity [1], which opens the way for different phenomena like slow light propagation or generation of quantum light states. Here, we experimentally create the giant Kerr nonlinearity, with the magnitude ranging from 1.2 x 10–7to 7.7 × 10–7m2V-2.