|<<< | >>>|
Optical pulses and regular optical pulse trains can be characterized in various respects:
- The pulse repetition rate is usually measured with a fast photodiode and an electronic spectrum analyzer.
- The pulse duration can be measured with various methods, e.g. with an autocorrelator or a streak camera. Optical sampling techniques can be used when a shorter reference pulse is available.
- The pulse energy may be measured directly or (for pulse trains) calculated from the average power and repetition rate.
- The peak power may be directly measured with a photodiode or calculated from pulse energy, pulse duration and pulse shape.
- The optical center frequency and spectral shape can be obtained with an optical spectrum analyzer.
- The carrier–envelope offset frequency is of special interest in optical metrology, and may be measured with an f−2f interferometer.
- The chirp can be measured e.g. with frequency-resolved optical gating.
- The timing jitter of a pulse train can be measured with various methods.
- The coherence (e.g. of subsequent pulses) can be characterized e.g. with an interferometer.
There are methods of complete pulse characterization , which reveal the electric field versus time or the complex spectrum (including spectral shape and spectral phase) of ultrashort pulses. The most prominent techniques for this purpose are FROG (frequency-resolved optical gating ) and SPIDER (spectral interferometry for direct electric-field reconstruction , → spectral interferometry). The results can be visualized in various ways, e.g. with graphs of time- or frequency-dependent functions, or with spectrograms.
Note that apart from the temporal aspect, there is also the spatial aspect . Both aspects are often approximately separated in the sense that the whole spatio-temporal profile of the electric field of a pulse can be specified as the product of two functions, one depending only on time and the other only on the spatial position. However, a significant coupling of temporal and spatial properties can occur in various situations. For example, pulses from Kerr lens mode-locked lasers often exhibit a time-dependent beam radius, which makes the complete characterization (and modeling) very challenging. Another spatio-temporal aspect is pulse front tilt, which is related to angular dispersion and can, e.g., result from a misaligned pulse compressor.
|||C. Yan and J. C. M. Diels, “Amplitude and phase recording of ultrashort pulses”, J. Opt. Soc. Am. B 8 (6), 1259 (1991)|
|||D. J. Kane and R. Trebino, “Characterization of arbitrary femtosecond pulses using frequency-resolved optical gating”, IEEE J. Quantum Electron. 29 (2), 571 (1993)|
|||K. C. Chu et al., “Direct measurement of the spectral phase of femtosecond pulses”, Opt. Lett. 20 (8), 904 (1995)|
|||I. A. Walmsley and V. Wong, “Characterization of the electric field of ultrashort optical pulses”, J. Opt. Soc. Am. B 13 (11), 2453 (1996)|
|||I. D. Jung et al., “High-dynamic-range characterization of ultrashort pulses”, Appl. Phys. B 65, 307 (1997)|
|||R. Trebino et al., “Measuring ultrashort laser pulses in the time–frequency domain using frequency-resolved optical gating”, Rev. Sci. Instrum. 68, 3277 (1997)|
|||C. Iaconis and I. A. Walmsley, “Spectral phase interferometry for direct electric-field reconstruction of ultrashort optical pulses”, Opt. Lett. 23 (10), 792 (1998)|
|||L. Gallmann et al., “Characterization of sub-6-fs optical pulses with spectral phase interferometry for direct electric-field reconstruction”, Opt. Lett. 24 (18), 1314 (1999)|
|||L. Gallmann et al., “Techniques for the characterization of sub-10-fs optical pulses: a comparison”, Appl. Phys. B 70, S67 (2000)|
|||L. Gallmann et al., “Spatially resolved amplitude and phase characterization of femtosecond optical pulses”, Opt. Lett. 26 (2), 96 (2001)|
|||J. W. Nicholson and W. Rudolph, “Noise sensitivity and accuracy of femtosecond pulse retrieval by phase and intensity from correlation and spectrum only (PICASO)”, J. Opt. Soc. Am. B 19 (2), 330 (2002)|
|||T. Hirayama and M. Sheik-Bahae, “Real-time chirp diagnostic for ultrashort laser pulses”, Opt. Lett. 27 (10), 860 (2002)|
|||E. M. Kosik et al., “Interferometric technique for measuring broadband ultrashort pulses at the sampling limit”, Opt. Lett. 30 (3), 326 (2005)|
|||S. Akturk et al., “The general theory of first-order spatio-temporal distortions of Gaussian pulses and beams”, Opt. Express 13 (21), 8642 (2005)|
|||A. S. Wyatt et al., “Sub-10 fs pulse characterization using spatially encoded arrangement for spectral phase interferometry for direct electric field reconstruction”, Opt. Lett. 31 (12), 1914 (2006)|
|||C. Dorrer, “High-speed measurements for optical telecommunication systems”, IEEE J. Sel. Top. Quantum Electron. 12 (4), 843 (2006)|
|||P. K. Bates et al., “Ultrashort pulse characterization in the mid-infrared”, Opt. Lett. 35 (9), 1377 (2010)|
|||M. Chini et al., “Characterizing ultrabroadband attosecond lasers”, Opt. Express 18 (12), 13006 (2010)|
|||G. Pariente et al., “Space–time characterization of ultra-intense femtosecond laser beams”, Nature Photonics 10 (547 (2016)|
See also: pulses, spectral phase, carrier–envelope offset, autocorrelators, frequency-resolved optical gating, spectral interferometry, streak cameras
and other articles in the categories optical metrology, light pulses
In the RP Photonics Buyer's Guide, 29 suppliers for equipment for pulse characterization are listed.
If you like this article, share it with your friends and colleagues, e.g. via social media: