We have experimentally studied the optical bistable behavior in an optical ring cavity filled with a collection of three-level L-type rubidium atoms, interacting with two collinearly propagating laser beams. The bistability so observed is very sensitive to the induced atomic coherence in this electromagnetically induced transparency system or consequently to the altered nonlinearity in the syst...

Kevin Cox,1 Valery I. Yudin,2,3,4 Alexey V. Taichenachev,2,3,4 Irina Novikova,1 and Eugeniy E. Mikhailov1 1Department of Physics, College of William & Mary, Williamsburg, Virginia 23185, USA 2Institute of Laser Physics SB RAS, Novosibirsk RU-630090, Russia 3Novosibirsk State Technical University, Novosibirsk RU-630092, Russia 4Novosibirsk State University, Novosibirsk RU-630090, Russia (Receive...

The electromagnetically induced transparency (EIT) in an N configuration is studied under both resonant and off-resonant conditions. In a certain off-resonant condition the dark state of the four level system, which is almost the same as the resonant dark state in Λ configuration, is rebuilt. The actual system with damping is examined using optical Bloch equation, both numerically and analytica...

The kinematics of a globally propagating disturbance (also known as an “EIT wave”) is discussed using Extreme UltraViolet Imager (EUVI) data from Solar Terrestrial Relations Observatory (STEREO). We show for the first time that an impulsively generated propagating disturbance has similar kinematics in all four EUVI passbands (304, 171, 195, and 284 Å). In the 304 Å passband the disturbance show...

We review developments, issues and challenges in Electrical Impedance Tomography (EIT), for the 4th Workshop on Biomedical Applications of EIT, Manchester 2003. We focus on the necessity for three dimensional data collection and reconstruction, efficient solution of the forward problem and present and future reconstruction algorithms. We also suggest common pitfalls or “inverse crimes” to avoid.

The large-scale coronal shock waves observed from radio type II bursts and from Moreton waves have proven surprisingly difficult to detect in coronal images. I review the evidence for such waves in radio, optical, EUV, and soft X-ray images. The data generally support the conclusion that the metric type II bursts can be identified with weak fast-mode shock waves launched at the impulsive phase ...

There are a number of interesting problems that could be tackled if the computing capacity of current EIT systems can be improved. We examined the performance of two such systems and found that a noticeable portion of the compute time is spent in finding the solution of sparse matrices. We developed and used a new sparse matrix testbench, Meagre-Crowd, to evaluate a selection of these sparse ma...

We show that very large nonlocal nonlinear interactions between pairs of colliding slow-light pulses can be realized in atomic vapors in the regime of electromagnetically induced transparency. These nonlinearities are mediated by strong, long-range dipole–dipole interactions between Rydberg states of the multi-level atoms in a ladder configuration. In contrast to previously studied schemes, thi...

A new approach to the measurement of gravitational fields with an equilibrium ensemble of ultra-cold alkali atoms confined in a cell of volume V is investigated. The proposed model of the gravitational sensor is based on a variation of the density profile of the ensemble due to changing of the gravitational field. For measurement the atomic density variations of the ensemble the electromagnetic...

Most existing phenomenological heat conduction models are expressed by temperature and heat flux distributions, whose definitions might be debatable in heat conductions with strong non-equilibrium. The constitutive relations of Fourier and hyperbolic heat conductions are here rewritten by the entropy and entropy flux distributions in the frameworks of classical irreversible thermodynamics (CIT)...