Pulse compression

Yelin D, Meshulach D and Silberberg Y 1997 Adaptive femtosecond pulse compression Opt. Lett. 22 1793-5... 

Treacy E B 1969 Optical pulse compression with diffraction gratings IEEE J. Quantum. Electron. 5 454-8... 

Johnson A M and Shank C V 1989 Pulse compression in single-mode fibres—picoseconds to femtoseconds The Supercontinuum Laser Source ed R R Alfano (New York Springer) pp 399-449... 

To carry out a spectroscopy, that is the structural and dynamical determination, of elementary processes in real time at a molecular level necessitates the application of laser pulses with durations of tens, or at most hundreds, of femtoseconds to resolve in time the molecular motions. Sub-100 fs laser pulses were realised for the first time from a colliding-pulse mode-locked dye laser in the early 1980s at AT T Bell Laboratories by Shank and coworkers by 1987 these researchers had succeeded in producing record-breaking pulses as short as 6fs by optical pulse compression of the output of mode-locked dye laser. In the decade since 1987 there has only been a slight improvement in the minimum possible pulse width, but there have been truly major developments in the ease of generating and characterising ultrashort laser pulses. 

This technique will allow compression of a 100-femtosecond pulse down to 12 femtoseconds or even to 8 femtoseconds. (A femtosecond is a millionth of a billionth of a second or 1 x 10-15 s.) Pulse compression can be used to study chemical reactions, particularly intermediate states, at very high speeds. Alternatively, these optical pulses can be converted to electrical pulses to study electrical phenomena. This aspect, of course, is of great interest to people in the electronics industry because of their concern with the operation of high-speed electronic devices. It also is of great interest to people who are trying to understand the motion of biological objects such as bacteria. 

High resolution may be obtained either with a short-duration pulse or by a coded wide-bandwidth signal, such as a linear FM chirp or a step-frequency sequence, with the appropriate pulse compression processing. A short-duration pulse requires a high peak transmit power and instantaneously-broadband operation these requirements can be relaxed in the case of pulse compression. 

It is seen that longitudinal dependences of the variation in the pulse duration plotted for 2 of the same modulus but different signs are approximately symmetrical with respect to the curve obtained in the quasistatic approximation. Hence, at normal GVD, the pulse duration is shorter than the initial one as a result of the self-focusing effect until, owing to GVD, this duration continuously increases to its initial value (denoted by asterisks) and then exceeds it. The size of the region within which the pulse compression is observed at decreases with increasing 2 - In turn,... 

While periodically-poled materials are typically characterized by very narrow spectral acceptance bandwidths (< 1 nm), aperiodically-poled structures (characterized by a linear gradient in grating period) have the advantage of providing sufficiently broad spectral acceptance bandwidths to utilize more of the spectrum associated with picosecond and femtosecond" pulses. They can also simultaneously provide some pulse compression of sufficiently pre-chirped incident pulses ... 

P. Loza-Alvarez, D.T. Reid, P. Faller, M. Ebrahimzadeh, W. Sibbett, H. Karlsson, and F. Laurell, Simultaneous femtosecond-pulse compression and second-harmonic generation in aperiodically poled KTiOP04, Optics Letters 24(15), 1071-1073 (1999). 

M.A. Arbore, O. Marco, and M.M. Fejer, Pulse compression during second-harmonic generation in aperiodic quasi-phase-matching gratings. Optics Letters 22(12), 865-867 (1997). 

Khaydarov, J. D., Andrews, J. H., and Singer, K. D. 1994. Pulse compression in a synchronously pumped optical parametric oscillator from group-velocity mismatch. Opt. Lett. 19 831-33. 

FIGURE 7.7 Usage of the pulse shaper to simplify SPIDER pulse compression, as employed in the SAC-SPIDER method (von Vacano et al. 2006b, 2007). See text for details. 

Meshulach, D., Yelin, D., and Silberberg, Y. 1997. Adaptive ultrashort pulse compression and shaping. Opt. Comm. 138(4-6) 345 8. 

Verluise, R, Laude, V., Cheng, Z., Spiehnann, C., and Toumois, P. 2000. Amplitude and phase control of ultrashort pulses by use of an acousto-optic programmable dispersive filter Pulse compression and shaping. Opt. Lett. 25(8) 575-77. 

Yue, G. Q., Nikoonahad, M and Ash, E. A. (1982). Subsurface acoustic microscopy using pulse compression techniques. IEEE 1982 Ultrasonics Symposium, pp. 935-8. IEEE, New York. [70]... 

Fowle, 1967] Fowle, E. (1967). The design of FM pulse-compression signals. IEEE Trans. Information Theory, 10 61-67. 

Key et al., 1959] Key, E., Fowle, E., and Haggarty, R. (1959). A method of pulse compression employing nonlinear frequency modulation, Technical report 207, Lincoln Laboratory, M.I.T. 

Pulse compression in optical fibers to remove distortion (Na, Cs)... 

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