8 research outputs found
Photonic crystal carpet: Manipulating wave fronts in the near field at 1550 nm
Ground-plane cloaks, which transform a curved mirror into a flat one, and
recently reported at wavelengths ranging from the optical to the visible
spectrum, bring the realm of optical illusion a step closer to reality.
However, all carpet-cloaking experiments have thus far been carried out in the
far-field. Here, we demonstrate numerically and experimentally that a
dielectric photonic crystal (PC) of a complex shape made of a honeycomb array
of air holes can scatter waves in the near field like a PC with a at boundary
at stop band frequencies. This mirage effect relies upon a specific arrangement
of dielectric pillars placed at the nodes of a quasi-conformal grid dressing
the PC. Our carpet is shown to work throughout the range of wavelengths 1500nm
to 1650nm within the stop band extending from 1280 to 1940 nm. The device has
been fabricated using a single- mask advanced nanoelectronics technique on
III-V semiconductors and the near field measurements have been carried out in
order to image the wave fronts's curvatures around the telecommunication
wavelength 1550 nm.Comment: 6 page
Microtechnologies for the monolithic fabrication of mm and submm non linear devices
We report on the recent development in microtechnology aimed at monolithically fabricating non linear devices at millimetre and submillimetre wavelengths. This approach will be illustrated with the fabrication of planar integrated Heterostructure Barrier Varactors and Schottky mixers for a use at 250 GHz and 500 GHz respectively. Also, epitaxial lift-off, followed by a transfer onto a host quartz substrate demonstrated here should permit us to further integrate the devices with the filtering and matching circuits in a monolithic fashion
Analytical model for the TeraHertz current noise in nanometric Schottky-barrier diodes and heterostructure barrier varactors
Dispersion engineering for multifunctional photonic crystal based nanophotonic devices at infrared wavelengths
TIn this paper, we report the design, the fabrication and the near field optical microscopy of Negative Index Material (NIM) and GRadient INdex (GRIN) photonic crystal based flat lenses. They were fabricated on the basis of an InPbased photonic crystal technological platform including hole and pillar networks fabrication at nanometer scale. They show the possibility of sub-wavelength focusing by all dielectric periodic or quasi-periodic crystals. Particular attention is paid to the analysis of SNOM images using three-dimensional simulations. Finally, in order to demonstrate the versatility of our approach, a two-dimensional cloaking device mixing hole and pillar arrays is evaluated to pave the way for future integrated nanophotonic devices with complex functionalities