1,721,096 research outputs found
New science and art of femtosecond laser writing
No full textCommon beliefs that laser writing does not change when reversing beam scan or propagation direction are challenged. Recently discovered phenomena of quill and non-reciprocal femtosecond laser writing in glasses and crystals are reviewed
Extraordinary stability of femtosecond direct written structures
No full textWe report novel results on the stability of femtosecond direct written structures: a silica sample previously irradiated with ultrashort pulses was annealed at increasing temperatures till 1400° C where it crystallized. Our results show that the birefringent direct written structures are stable till a temperature close to the glass transition of silica. After annealing at a temperature as high as 1100° C the form birefringence of the structures is still present, proving that the nature of the laser induced anisotropy is related to a structural change
Self-assembled sub-wavelength structures and form birefringence created by femtosecond laser writing in glass: properties and applications
No full textProperties and applications of self-assembled sub-wavelength structures and related form birefringence produced by femtosecond laser writing in silica glass are reviewed
Recent advances in femtosecond laser direct writing of integrated optical elements
No full textUltrafast-laser materials processing, including modification of transparent matter, has become an attractive and rapidly developing area of research with applications from integrated optics to laser surgery. Interaction of femtosecond light pulses with matter is not yet fully understood and can lead to unexpected findings. For instance, formation of self-assembled nanogratings was observed inside fused silica glass when irradiated with ultrafast-laser. This type of modification enables controlling anisotropic structures inside isotropic glass medium and can be applied for polarization control devices.Another intriguing effect is quill like behaviour of femtosecond laser beam with tilted intensity front. The effect manifests as the difference in material modification when moving a sample from left to right and vice versa. Recently, it was demonstrated that pulse front tilt can be responsible not only for directional dependence but also for anisotropic photosensitivity of isotropic medium. It was shown that pulse front tilt can be used as a new tool for laser processing and optical manipulation.In the nearest future we will seek for the applications of the observed effects in biology and quantum optics
Waveguide fabrication in bismuthate glasses using femtosecond laser pulses
No full textFemtosecond direct written waveguides in bismuthate glasses are reported. This is the first demonstration of direct written guiding channels in bismuthate glass which show an index of refractive change as high as 3 x 10-3
Ultrafast laser direct writing and nanostructuring in transparent materials
No full textAn overview of recent achievements in the field of femtosecond laser writing in transparent materials is presented. Thanks to the unique properties of light–matter interaction on the ultrashort time scale, this direct writing technique has led to observation of unique phenomena, including nonreciprocal writing and anisotropic photosensitivity, in transparent materials and allowed engineering of novel photonic devices
Fibre optics for atom detection
No full textThe use of atom chips for the manipulation cooling and investigation ofneutral atoms isnow well developed with the current carrying wires used for transport and production of magnetic traps being integral parts of the chip. Such devices offer the possibility of scalable quantum information processing. A further step towards compact efficient devices would be the integration of the required optical elements both for detection and manipulation of the atoms. To this end we are working to mount standard fibre optical components onto the chip with the goal of single atom detection. At present, two man directions are being pursued: Fluorescence detection and fibre Fabry Perot gap cavities Theoretical analysis has shown that both devices will have the ability to detect single atoms with the micro-cavities offering the possibility of non-destructive detection
Symmetric waveguides written in Er<sup>3+</sup>-doped Bi<sub>2</sub>O<sub>3</sub>-based glass using femtosecond laser pulses
No full textSingle-mode channel waveguides are fabricated in Er-based glass using femtosecond laser pulses at 800nm. A waveguide with circular transverse profile is demonstrated without using any beam shaping technique
Polarization sensitive camera by femtosecond laser nanostructuring
No full textA polarization imaging device based on a femtosecond laser nanostructured birefringent array is demonstrated. The device enables instant measurement of the distribution of the Stokes vectors in the visible spectrum. Polarimetric measurements with radially and circularly polarized light distributions are demonstrated
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