G. S. Agarwal

Class of solitary wave solutions of the one-dimensional Gross-Pitaevskii equation.

We present a large family of exact solitary wave solutions of the one-dimensional Gross-Pitaevskii equation, with time-varying scattering length and gain or loss, in both expulsive and regular parabolic confinement regimes. The consistency condition governing the soliton profiles is shown to map onto a linear Schrödinger eigenvalue problem, thereby enabling one to find analytically the effect of a wide variety of temporal variations in the control parameters, which are experimentally realizable. Corresponding to each solvable quantum mechanical system, one can identify a soliton configuration. These include soliton trains in close analogy to experimental observations of Streckeret al. [Nature (London) 417, 150 (2002)], spatiotemporal dynamics, solitons undergoing rapid amplification, collapse and revival of condensates, and analytical expression of two-soliton bound states, to name a few.

Fano resonances and their control in optomechanics

The Fano line profiles, originally discovered in the context of photoionization, have been found to occur in a large class of systems like resonators, metamaterials, plasmonics. We demonstrate the existence of such resonances in cavity optomechanics by identifying the interfering contributions to the fields generated at antiStokes and Stokes frequencies. Unlike the atomic systems, the optomechanical systems provide great flexibility as the width of the resonance is controlled by the coupling field. We further show how the double cavities coupled by a single optomechanical mirror can lead to the splitting of the Fano resonance and how the second cavity can be used to tune the Fano resonances. The Fano resonances are quite sensitive to the decay parameters associated with cavities and the mechanical mirror. Such resonances can be studied by both pump probe experiments as well as via the spectrum of the quantum fluctuations in the output fields.

Correlation measurements with on-off detectors

We present a general method to detect nonclassical radiation fields with systems of on-off detectors. We especially study higher order correlations for the identification of nonclassical radiation. This allows us to directly characterize quantum correlations by the statistics measured with systems of on-off detectors. Additionally, we generalize our method to multiple detector systems for measurements of correlations between light fields. We also consider multi-mode radiation fields and isolate nonclassicality in terms of the space time correlations. Finally, we present results for the quantum statistics using on-off detectors operating in nonlinear detection modes.

Nonlocal continuous-variable correlations and violation of Bell's inequality for light beams with topological singularities

We consider optical beams with topological singularities which possess Schmidt decomposition and show that such classical beams share many features of two mode entanglement in quantum optics. We demonstrate the coherence properties of such beams through the violations of Bell inequality for continuous variables using the Wigner function. This violation is a consequence of correlations between the

Large enhancement of Förster resonance energy transfer on graphene platforms

(x, p_x)

Einstein-Podolsky-Rosen steering using quantum correlations in non-Gaussian entangled states

and

Multimode phonon cooling via three-wave parametric interactions with optical fields

(y, p_y)

Dynamical quantum theory of heat transfer between plasmonic nanosystems

spaces which mathematically play the same role as nonlocality in quantum mechanics. The Bell violation for the LG beams is shown to increase with higher orbital angular momenta

Observation of electromagnetically induced transparency in evanescent fields.

l

Goos-Hänchen shifts in harmonic generation from metals

of the vortex beam. This increase is reminiscent of enhancement of nonlocality for many particle Greenberger-Horne-Zeilinger states or for higher spins. The states with large