Photoelastic in-fibre birefringence modulator operating at the fundamental transverse acoustic resonance

A Highly efficient photoelastic in-fiber birefringence modulator is demonstrated. It operates at the acoustic frequency ~23MHz which corresponds to the fundamental transverse acoustic resonance of a 125µm diameter silica fiber. Using an analyzer at the output end of the fiber we obtained ~90% amplitude modulation for an RF power of 0.7 W

Acousto-optic in-fibre modulator using acoustic focusing

A new efficient in-fibre acousto-optic phase modulator is demonstrated in which the acoustic wave is focused onto the fibre by reflection from a cylindrical surface. The device exhibits a phase modulation of 2.63 radians at the light wavelength of 1550 nm, using an RF frequency of 86 MHz and a power of 1W

Ultrafast Laser Nanostructured ITO Acts as Liquid Crystal Alignment Layer and Higher Transparency Electrode

Electrodes with higher transparency that can also align liquid crystals (LCs) are of high importance for improved costs and energy consumption of LC displays. Here we demonstrate for the first time alignment of liquid crystals on femtosecond laser nanostructured indium tin oxide (ITO) coated glass exhibiting also higher transparency due to the less interface reflections. The nano paterns were created by fs laser directlly on ITO films without any additional spin coating materials or lithography procces. Nine regions of laser-induced nanostructures were fabricated with different alignment orientations and various pulse energy levels on top of the ITO. The device interfacial anchoring energy was found to be comparable to the anchoring energy of nematic LC on photosensitive polymers. The device exhibits contrast of 30:1 and relaxation time of 330ms expected for thick LC devices. The measured transparency of the LC device with two ITO nanograting substrates is 10% higher than the uniform ITO film based LC devices. The alignment methodology presented here paves the way for improved LC displays and new structured LC photonic devices

Oblique frozen modes in periodic layered media

We study the classical scattering problem of a plane electromagnetic wave incident on the surface of semi-infinite periodic stratified media incorporating anisotropic dielectric layers with special oblique orientation of the anisotropy axes. We demonstrate that an obliquely incident light, upon entering the periodic slab, gets converted into an abnormal grazing mode with huge amplitude and zero normal component of the group velocity. This mode cannot be represented as a superposition of extended and evanescent contributions. Instead, it is related to a general (non-Bloch) Floquet eigenmode with the amplitude diverging linearly with the distance from the slab boundary. Remarkably, the slab reflectivity in such a situation can be very low, which means an almost 100% conversion of the incident light into the axially frozen mode with the electromagnetic energy density exceeding that of the incident wave by several orders of magnitude. The effect can be realized at any desirable frequency, including optical and UV frequency range. The only essential physical requirement is the presence of dielectric layers with proper oblique orientation of the anisotropy axes. Some practical aspects of this phenomenon are considered.Comment: text and 9 figure

Cavity dumping of neodymium-doped fibre lasers using acousto-optic modulator

We report high-repetition-rate pulses obtained by cavity dumping of a neodymium-doped phosphate glass fibre laser operating at 1053 nm using a specially constructed acoustooptic modulator. With 27 mW absorbed pump power at 812 nm we obtained stable trains of output pulses with repetition rate in the range 0.5 to 8MHz having corresponding pulse widths in the range 127 to 19 ns without significant sacrifice in the average output power of 8 mW

Guest editorial: Selected papers from the first joint israeli-turkish workshop on nanophotonics

[No abstract available

Special section guest editorial: Selected papers from the 4th Mediterranean Conference on Nanophotonics

[No abstract available

Guest editorial: Mediterranean nanophotonics

[No abstract available

Guest editorial: Selected papers from the 2nd mediterranean conference on nanophotonics

[No abstract available

Special section guest editorial: Selected papers from the 3rd mediterranean conference on nanophotonics

[No abstract available