In this talk we will present an overview of recent development of ultrafast lasers sources and their applications. This talk will highlight some recent state of the art ultrafast pulse results from Ti:Sapphire and Ytterbium based laser systems. There are significant advantages in being able to directly diode pump Ytterbium materials resulting in more compact bulk solid state and fiber based laser systems. Several newly emerging technologies such as Optical Parametric Chirped Pulse Amplification, and Supercontinuum Generation have generated great excitement in recent years. The evolution of more compact and user friendly ultrafast laser systems has enabled completely new fields that take advantage of the extremely high peak powers and very short time duration of ultrafast laser pulses. Recent results in the fields of multiphoton microscopy, micromachining, 3-D fabrication, and spectroscopy will be discussed.

A high-precision 3D structuring of dielectrics by sub-1 ps pulses is possible by dielectric breakdown and opens an unique possibility to create a high temperature electrons inside material under processing. The 3D nano/micro-structuring by dielectric breakdown is numerically simulated by 3D finite-differences time domain (FDTD) calculations where the plasma is simulated by a nanosphere of metal (gold). The effect of anisotropic light scattering in the plane of incident polarization has been qualitatively explained by light inteaction with ionized (metalic) focal volume. It is shown that the experimentaly achieved densification of materials after irradiation by tightly focused sub1 ps pulses is consistent with formation of new high-pressure phases.

Thermal effects are unavoidable in laser material processing and are present, to some extent, even in the case when ultra-short (sub-picosecond) pulsed irradiation is used. We discuss here the matters of high-precision energy delivery into micrometer-sized volumes for three-dimensional (3D) laser microfabrication. Precise account of the absorbed energy, pulse duration, and focal spot size allows to optimize laser processing parameters. As an example, a 3D micro-structuring of silica with better than 15 mu m resolution is demonstrated by pulses of 11 ns duration and 266 nm wavelength (for a focusing by a low numerical aperture NA = 0.029 lens). The two photon absorption coefficient of silica, beta similar or equal to 60 +/- 10 cm/GW, at 266 nm has been determined.The thermal black-body type emission of non-equilibrated electrons is discussed as a possible light source for 3D modification and structuring of photo-sensitive and photo-polymerizable materials. It is also demonstrated that optical properties of ionized dielectrics can be used to determine the temperature.