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Atoms of four-level atomic medium are doped in a crystal slab of silica which is immersed in a four-level atomic medium. We incorporated Bragg law in the Rabi frequencies of the driving fields and obtained absorption spectrum which exhibits atom localization inside the crystal plane and generation of waveguide channels. Varying the Bragg angle θ, leads to a number of localized peaks and craters. The number of peaks decreases as we increase the Bragg angle θ from π/8 to π/2 and the peaks disappear beyond this angle. The localization probability is independent of the Bragg angle, while the spatial resolution varies with change in Bragg angle. However, the probe detuning and amplitudes of Rabi frequencies change the localization probability. Inside the optical lattice of the silica crystal, waveguide channels and particle traps are generated which may be utilized to guide electromagnetic radiations and trap quantum particles. This work is useful for coherent control information of crystal planes, optical trapping, waveguide channels of nano crystals and data storage.

The absorption coefficients, refractive/group indices, phase shifts and fractional change of birefringence beams through dynamic chiral atomic medium are investigated under the effect of quantum tunnelling. The birefringence of phase indices Δ n = n r ( + ) − n r ( − ) and group indices Δ n g = n g ( + ) − n g ( − ) are controlled and modified through induced dynamic chiral medium by tunnelling effect. The group indices n g ( ± ) = ± 500 and group velocities v g ( ± ) = ± c / 500 are reported with the tunnelling effect. The maximum change in birefringent phase shifts is calculated to 5 microradian with tunnelling frequency at a speed of v = 10 cm/s of the chiral medium in the right circularly polarized (RCP) and left circularly polarized (LCP) beams. A 60% fractional change in the phase shift of RCP and LCP beams are investigated through induced chiral medium when the medium is at rest and when it is moving with the speed of v = 10 cm/s. These results will play an important role in scatterplate phase shifting interferometry.

The dielectric tensor of four level atomic medium coupled with dielectric function of silver silica nano-composites material to modify dispersion relation of surface plasmon polaritons (SPPs). The rapid damping of SPPs is used to localized atomic particles in two dimension inverse position space. Directions, phases and intensity of the control field play important roles in the localization of atoms in a unit wavelength domain. Ten, six, four and two localization peaks are investigated by SPPs damping in different quadrants. A single broad localized peak symmetric about origin are also investigated. The theoretical work of this article may be useful for quantum information in Plasmonster technology.

The birefringence of rotary photon drags is investigated through induced chiral atomic medium. The birefringence of refractive and group indices, divergent angle and rotary photon drags were controlled and modified with detuning, phases and strength of Rabi frequencies of the driving fields. The value of divergent angle oscillated between ±0.01 radian with phases of control fields 3,4 and is minimum at 3 = π, while maximum at 4 = π. The left and right circularly polarized beams are drag clockwise due clockwise spinning of the medium in the normal dispersive region, while the left and right circularly polarized beams are drag clockwise due anticlockwise spinning of the medium in anomalous dispersive region. The maximum rotary photon drags of birefringent beams of light is calculated to ±5 milli radian. The results show advancement in molecular structure, dual image coding and image designing technology.

We investigate the behavior of light propagation in an N-type four-level gain assisted model (Agarwal and Dasgupta 2004 Phys. Rev. A 70 023802) under poly-chromatic pump fields. The system exhibits interesting results of multiple controllable pairs of the gain doublet profile with changes in the intensity of the control field. We observe multiple anomalous dispersive regions for superluminal propagation in the medium. A negative group velocity of −37.50 m s−1 with a negative time delay of −8 ms is observed between each gain doublet in anomalous dispersive regions. This generalized model and its predictions can be tested with existing experimental setups.