Wireless adiabatic power transfer

We propose a technique for efficient mid-range wireless power transfer between two coils, by adapting the process of adiabatic passage for a coherently driven two-state quantum system to the realm of wireless energy transfer. The proposed technique is shown to be robust to noise, resonant constraints, and other interferences that exist in the neighborhood of the coils.Comment: 11 pages, 6 figure

Quantum coherent control of highly multipartite continuous-variable entangled states by tailoring parametric interactions

The generation of continuous-variable multipartite entangled states is important for several protocols of quantum information processing and communication, such as one-way quantum computation or controlled dense coding. In this article we theoretically show that multimode optical parametric oscillators can produce a great variety of such states by an appropriate control of the parametric interaction, what we accomplish by tailoring either the spatio-temporal shape of the pump, or the geometry of the nonlinear medium. Specific examples involving currently available optical parametric oscillators are given, hence showing that our ideas are within reach of present technology.Comment: 14 pages, 5 figure

Quasicrystals: Making invisible materials

All-dielectric photonic quasicrystals may act as zero-refractive-index homogeneous materials despite their lack of translational symmetry and periodicity, stretching wavelengths to infinity and offering applications in light wavefront sculpting and optical cloaking.Comment: 5 pages, 2 figure

Highly efficient broadband sum-frequency generation in the visible wavelength range

We report on efficient broadband sum-frequency generation, converting a 140 THz near-infrared bandwidth to the visible regime with photon conversion efficiency greater than 90%. Using a 20-mm-long aperiodically adiabatively poled KTP crystal, the spectral range 660–990 nm was converted to 405–500 nm using a strong pump wave at 1030 nm. The photon conversion efficiency was confirmed to be 92±0.5% when pumped with an intensity of 0.94  GW/cm2. Our experimental results agreed very well with analytic predictions and numerical simulations