Femtosecond and ultrashort pulsed lasers are finding potential new application in industrial and medical laser applications.  Finding solutions for laser beam shaping of intense laser pulses is critical to providing optimized, controlled and precision laser processing.  Many of the new methods being researched are going to presented at the LBS-IX conference and those abstracts are highlighted for review.

Smart spatio-temporal beam shaping with thin-film microoptics (Invited Paper) 

Paper 7062-1   
Author(s): Ruediger Grunwald, Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie (Germany)

Abstract

After two decades of research, the enormous potential of advanced thin-film microoptics for tailoring light fields of pulsed high-power laser even at extreme parameters is well demonstrated. This keynote lecture gives a comprehensive review of the state of the art and the most relevant aspects of this branch of modern optics. In particular, the application of structured dielectric, metallic and compound layers and programmable liquid-crystal devices for control and diagnostics of ultrashort pulses in space and time is discussed. Recent theoretical and experimental results of wavefront sensing, multichannel materials processing and information encoding are presented here.   

Formation of femtosecond bessel and conical light beams by single and double axicons 

Paper 7062-2   
Author(s): Svetlana N. Kurilkina, Vladimir N. Belyi, Nikolai S. Kazak, Anatolii A. Ryzhevich, B.I. Stepanov Institute of Physics (Belarus)

 
Abstract

The properties of the transformation of a pulse beam to femtosecond Bessel light beam (FBLB) using axicons are investigated theoretically and experimentally. The dependence of group velocity of FBLB on dispersion of the axicon material and its base angle is established. The appearance of super-short satellite pulse with envelope maximum depending on incident pulse duration is predicted and correctly explained. New techniques for controlling the spatial form of FBLB, based on including additional lenses and tunable-diameter diaphragm are developed and experimentally tested. A new method of forming the super-short pulsed beams of Bessel type using double-axicon is proposed and elaborated.   

     
       
Micro-optic array applications in terawatt ultrafast laser amplifiers 

Paper 7062-3   
Author(s): Barry C. Walker, Isaac Ghebregziabher, Sasi Palaniyappan, Anthony DiChiara, Univ. of Delaware

 
Abstract

Recent developments in micro-optics offer the potential of higher power, more robust ultrafast laser technology operating at high efficiency. Results using micro-optic lenslet arrays in an ultrafast, Ti:sapphire terawatt amplifier are presented. We report a final ultrafast amplified laser mode can be shaped to within 1% of the target Gaussian at a pump energy to laser pulse energy conversion efficiency of 35%. Focusing studies demonstrate the laser system with microlens arrays can achieve a peak intensity of 10^(19) W/cm^2. Future applications of microlens arrays in 100 terawatt and possibly petawatt peak power systems will be discussed.  

       
Compression of ultrashort pulses by using refractive elements 

Paper 7062-4   
Author(s): Cristtel Y. Ramírez-Corral, Martha Rosete-Aguilar, Jesus Garduño-Mejía, Roberto Ortega-Martínez, Univ. Nacional Autónoma de México (Mexico)


Abstract

In prisms the main effects that modify the temporal characteristics of the pulse is the group velocity dispersion which can be interpreted as a result of angular dispersion of each of the electromagnetic waves of the pulse and the group velocity dispersion introduced by the glass material constituting the prisms. A model for the compression of ultrashort light pulses is presented for a set of prisms. This model is then applied to refractive lenses. Preliminary theoretical results in our group suggest that it is possible to compensate temporal and spatial spreading of a pulse as it passes through the lens. Discussion and results are presented.

    
       
Optical pulse shaping and applications (Invited Paper) 

Paper 7062-6   
Author(s): Andrew M. Weiner, Purdue Univ.

Abstract

Femtosecond optical pulse shaping is by now an established technology allowing generation of essentially arbitrary ultrafast optical waveforms according to user specification. Waveform generation is accomplished via a Fourier synthesis method, which reflects phase, amplitude, and polarization information placed onto the optical spectrum via a spatial light modulator. Applications span lightwave communications, coherent control of quantum mechanical processes, few femtosecond pulse compression, nonlinear optical microscopy, and microwave photonics. In this talk I will first discuss the basics of pulse shaping and then survey recent topics of interest within my group at Purdue University.