Accession Number : ADA546659


Title :   Single-cycle Pulse Synthesis by Coherent Superposition of Ultra-broadband Optical Parametric Amplifiers


Descriptive Note : Final rept. 2 Sep 2009-2 Sep 2010


Corporate Author : POLITECNICO DI MILANO (ITALY)


Personal Author(s) : Cerullo, Giulio


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a546659.pdf


Report Date : Aug 2011


Pagination or Media Count : 45


Abstract : Ultrafast optical science has experienced major breakthroughs in the last years, driven by two main accomplishments: (i) generation of light pulses with duration of just a few cycles of the optical carrier wave; (ii) control of the carrier-envelope phase (CEP) of light pulses, enabling the production of optical waveforms with reproducible electric field. The generation of extremely short light pulses with controlled CEP allows exploring new frontiers of light-matter interaction, entering the so-called ?extreme nonlinear optics regime. In particular, by focusing high-intensity pulses in a noble gas jet, it is possible to produce coherent bursts of XUV radiation by the so-called High Harmonic Generation (HHG) process. Such pulses can have a duration down to approximately 100 as. Attosecond pulses open entirely new perspectives in the study of ultrafast processes relevant to chemical reactions, material science and most importantly the structure and function of biomolecules. Approaching the pulse duration limit set by the period of the optical carrier wavelength (2-3 fs in the visible to near-IR range) is challenging because of the requirement to control the pulse spectral amplitude and phase over an ultrabroad bandwidth. It has long been recognized that (sub)single-cycle optical pulses may be generated through phase coherent superposition of several independent few-cycle laser pulses tuned to different carrier frequencies. A great deal of experimental work has been carried out on coherent pulse synthesis from two separate broadband mode-locked laser oscillators; such task is however very demanding because it requires synchronization of two laser cavities to within a fraction of the carrier period (100- 200 as). In addition, synchronization of two oscillators allows generating only limited pulse energies (of the order of 1 nJ), which are not sufficient to drive the HHG process.


Descriptors :   *AMPLIFIERS , *OPTICAL PROPERTIES , REQUIREMENTS , OPTICS , HIGH RATE , PRODUCTION , INTERACTIONS , SYNTHESIS , MATERIALS , WAVEFORMS , COHERENCE , INTENSITY , ELECTRIC FIELDS , NONLINEAR OPTICS , PULSE RATE , SPECTRA , LIMITATIONS , LIGHT PULSES , CHEMICAL REACTIONS , VISIBILITY , BROADBAND , SYNCHRONIZATION(ELECTRONICS) , FOCUSING , REPRODUCIBILITY , NEAR INFRARED RADIATION , WAVES , SHORT PULSES , CARRIER FREQUENCIES , PULSE AMPLITUDE , MODE LOCKED LASERS , RARE GASES , BIOMOLECULES , HARMONIC GENERATORS , FAR ULTRAVIOLET RADIATION , OSCILLATORS , LASER CAVITIES


Subject Categories : Electrical and Electronic Equipment
      Optics


Distribution Statement : APPROVED FOR PUBLIC RELEASE