Laser micro-fabrication/manipulation of dielectric materials

We describe microfabrication of various materials by multi-photon absorption (MPA) of femtosecond (120-150 fs) light pulses. The photo-modification at the focal point of tightly focused laser beam occurs inherently within volume smaller than that defined by the diffraction limit. The achievable lateral resolution is compared with that obtainable by lithography which uses near-field optical microscopy (NSOM). This technique can in principle lead to the realization of 3D optical memory and photonic crystals (PhC) with arbitrary lattice in polymers and silica glass, 3D prototyping in polymerizable resins, and etching of 3D structures guided by the optically damaged pattern in silica. Another topic also discussed in this work deals with laser micromanipulation using continuos wave (cw) laser operating at 1.06 mum. Light-controlled revolution of liquid crystal droplet and volume-phase transition of gel will be described.