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Electromagnetically induced phase grating via population trapping condition in a microwave-driven four-level atomic system
, Article Journal of the Optical Society of America B: Optical Physics ; Vol. 31, issue. 11 , November , 2014 , p. 2879-2884 ; ISSN: 07403224 ; Sadighi-Bonabi, R ; Sharif University of Technology
Abstract
An electromagnetically induced phase grating (EIG) controlled by coherent population trapping (CPT) in a fourlevel Y-type atomic system is studied. The CPT condition promotes significantly the dispersion of light into the first-order diffraction in constructing a phase modulation grating by transferring energy from zero-order to firstorder diffraction. The diffraction efficiency of the phase grating is enhanced by up to 30% of the total probe intensity at the first-order diffraction. The present atomic scheme takes full advantage of the microwave-driven field for generating the EIG, which induces the quantum coherence and controls linear and nonlinear behaviors of the present system....
Effect of Negative Index Metamaterial on the Optical Properties of Surface Polariton
, M.Sc. Thesis Sharif University of Technology ; Sadighi-Bonabi, Rasoul (Supervisor)
Abstract
A coupler free scheme for directly exited surface polariton (SP) using a negative-index metamaterial (NIMM) with a bottom layer of N type quantum emitters is presented. It is shown that by suppressing the ohmic loss the giant field enhancement could be achived in a broad electromagnetically induced transparency (EIT). And this field enhancement cause the excitation of surface polariton at the NIMM-Quantum emitter interfaces. For large range of probe detuning in EIT position and the tunable excitation of SP could be accomplished for special probe angle.It is revealed that the linear and nonlinear optical properties could be controlled effectively by modulating the phase of the microwave...
Electromagnetically induced grating in the microwavedriven four-level atomic systems
, Article Applied Optics ; Volume 54, Issue 3 , 2015 , Pages 368-377 ; 1559128X (ISSN) ; Naseri, T ; Navadeh Toupchi, M ; Sharif University of Technology
Abstract
A new scheme to investigate an electromagnetically induced grating in an N-type configuration in the presence of a strong-standing coupling field, additional coherent fields, and microwave driven fields is presented. By considering the coherent population trapping (CPT) condition in a four-level microwave drivenN-type atomic system, a novel nonlinear optical storage is obtained via linear absorption vanishing and giant Kerr nonlinearity during light propagation. It is revealed that nonlinear properties in this atomic medium are maximum in the CPT condition, and these nonlinear properties could be affected and modulated by means of a microwave driven field. In this condition high-phase...