Laser, high repetition rate

To observe the transient spatiotemporal structure of the WP interference, we have performed the fs pump-fs probe experiment [37], The sample gas was prepared by molecular jet expansion of the mixture of iodine vapor and Ar buffer gas into a vacuum chamber. A continuous gas jet is preferable when we use a high-repetition-rate laser system. The estimated vibrational temperature was 170K[37]. 

An additional component of this application is the use of a high-repetition-rate laser that delivers pulses at frequencies up to 1400 Hz. Historically, MALDI ion... 

Hatsis, P., Brombacher, S., Corr, J., Kovarik, P., and Volmer, D. A. (2003). Quantitative analysis of small pharmaceutical drugs using a high repetition rate laser matrix-assisted laser/ desorption ionization source. Rapid Commun. Mass Spectrom. 17 2303-2309. 

Stimpfle R. M. and Anderson J. G. (1988) In situ detection of OH in the lower stratosphere with a balloon borne high repetition rate laser system. Geophys. Res. Lett. 15, 1503-1506. 

Falconieri, M. Thermo-optical effects in Z-scan measurements using high-repetition-rate lasers. J. Opt. A Pure Appl. Opt. 1, 662-667 (1999)... 

Hz however, higher repetition rafe lasers radiaf-ing in the same wavelength region do exist. The problem with using these high repetition rate lasers is that the CARS data acquisition hardware is limited by the rate at which it can store the spectra. If fhe number of points per spectrum was reduced and/or the data capture rate limit is increased then lasers with higher repetition rate could be used. The next most important component in the CARS setup is the detection system. As indicated above, a sensitive detector with the least susceptibility to noise and non-linearities will result in measurements with the least machine dependant statistics. Commercially available dye lasers can be used for the Stokes laser however, for reasons of expediency, simplicity, and economy, a home built dye laser is sufficient. 

For a long time the most difficult problem of pulse-group multiplexing has been the lasers. Conventional high-repetition rate lasers cannot be turned off and on at sub-ps speed, and simple optical switches of the required speed and on-off ratio do not exist. Picosecond diode lasers, however, can be switehed on within less than a microsecond and switched off within one or two pulse periods. Diode lasers with multiplexing capability are currently available for 375 nm, 405 nm,... 

The simplest and most accurate way to calibrate a TCSPC system is to use the pulse period of a high repetition rate laser as a time standard. The pulse period of Ti Sapphire lasers is between 78 and 90 MHz and accurately known. Diode lasers are usually controlled by a quartz oscillator and have an absolute frequency accuracy of the order of several tens of ppm. The signal is recorded in the reversed start-stop mode with a frequency divider in the reference path. The recorded waveform covers several laser periods, and the time between the pulses can be measured and compared with the known pulse period. 

Experimental Setup. In general, at the heart of a continuum pump-probe experiment is a high repetition rate laser. This can be a passively mode-locked CPM laser which is pumped by a cw Ar laser and which produces pulses typically shorter than 100 fsec around 620 nm with a pulse energy of approximately 0.1 nJ. Alternatively, a mode-locked Nd-YAG laser (532 nm) pumps a dye laser. In that case pulses at somewhat shorter wavelengths can be obtained, which are higher in energy when the same repetition rate is used (typically 0.5 nJ), but the pulses are usually longer, even after pulse compression (>100 fsec). 

Saiki T, Motokoshi S, Imasaki K, Fujioka K, Yoshida H, Fujita H et al (2(K)9) High repetition rate laser pulses amplified by Nd/CnYAG ceramic amplifier under CW are-lamp-light pumping. Opt Commun 282 2556—2559... 

Recently (Corr 2006) a detailed account of design considerations for, and initial performance characteristics of, a MALDI-MS/MS instrument for high speed quantitative analysis of small molecules has described incorporation of most of the considerations of the preceding paragraph. The use of a triple quadrupole analyzer in MRM mode with a high repetition rate laser avoids the disadvantages associated with use of an o-MALDI-TOF... 

Golberg D, Rode A, Bando Y et al (2003) Boron nitride nanostructures formed by ultra-high-repetition rate laser ablation. Diamond Relat Mater 12 1269-1274... 

Rode, A.V., Gamaly, E.G., Luther-Davies, B., 2000. Formation of cluster-assembled carbon nano-foam by high-repetition-rate laser ablation. Appbed Physics A 70 (2), 135—144. 

Photopolymerization processes using high repetition rate laser pulses... 

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