Advances in Ultrafast Optics || 1. Ultrafast ultrahigh-intensity laser pulses
DOI:10.1515/9783110304558-001
出版年份:2018
更新时间:2025-09-16 10:30:52
摘要:
Generation of high intensity laser pulses has been regarded as one of the most important research topics since the invention of lasers. High intensity lasers are normally constructed using the master oscillator power amplifier (MOPA) configuration to boost the energy of short laser pulses. This configuration has been used in various locations such as the Shenguang facilities in China and the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) in the USA; the latter is currently the largest laser facility in the world. This type of giant laser facility is usually employed for high-cost and large-scale scientific projects involving complex technology and only a few countries can perform this type of laser research. Because of the low repetition rate and long pulse duration of the achieved laser pulses, these laser facilities are not suitable for large-scale applied research. Furthermore, the output laser intensity is limited. For example NIF, constructed in 2009, includes 192 ultraviolet (UV) beams with the total energy up to 1.8 megajoules (MJ, 106 J). However, the peak power is only approximately 500 terawatts (TW; 1012 W) [1] because the pulse duration is at the nanosecond (ns; 10?9 s) level; the separation time between two pulses is as long as a few hours. At the other end of the scale, several research institutes have developed tabletop laser systems within regular-scale labs through the amplification of ultrashort-pulse lasers at the femtosecond (fs; 10?15 s) level. These lasers have peak powers at the petawatt (PW; 1015 W) level [2–4], a repetition rate of 1 hertz (Hz) [5], and a focus intensity reaching 1022 W/cm2 [6]. As a result of the 1991 discovery of the Kerr-lens mode-locking (KLM) phenomenon by the Sibbett group in the UK [7], along with the development of chirped pulse amplification (CPA) technology by the US-based Mourou group in 1985 [8], and research on ultrashort pulses, ultrahigh-intensity lasers have been advancing at an unprecedented pace since the late 1980s. New scientific records associated with significant breakthroughs have been made on a continuous basis. Ultrashort-pulse laser research has developed in two explorative directions. One path of development targets extremely short pulse duration promoted by mode-locking technology. Currently, laser pulse duration can reach the few-cycle level; in addition, attosecond (as; 10?18 s) laser pulses can be achieved using new physical mechanisms [9–11]. The second research trend is the ongoing extension of the laser peak power limit. An increasing number of femtosecond ultrahigh-intensity laser facilities with peak powers at the terawatt or even petawatt level have been developed [2–5], serving as powerful tools for in-depth research on ultrafast, ultrahigh-intensity laser pulses. Ultrashort pulses and ultrahigh-intensity laser technology are not only extensively employed in the fields of micromanufacturing [12–14] and medicine [15, 16] but have also been successfully and prominently implemented in various research areas, such as the exploration of atomic and molecular motion patterns [17, 18], laboratory simulations in astrophysics [19], and precision spectroscopy [20]. These applications have facilitated the emergence of many new subfields and groundbreaking scientific achievements. One of the two most representative events was the award of the 1999 Nobel Prize in Chemistry to the American researcher, Prof. A. H. Zewail. This prize was awarded for work on chemical kinetics using femtosecond laser pulses. The second representative achievement was the joint sharing of one half of the 2005 Nobel Prize in Physics by Profs. J. L. Hall and T. W. H?nsch; this prize was awarded for their achievements regarding the femtosecond laser frequency comb technique. With state-of-the-art features and innovative applications, ultrashort pulses, ultrahigh-intensity lasers have become crucial tools in the field of optical physics. Therefore, this chapter will first briefly review the essential technology and associated progress in research.
作者:
Zhiyi Wei,Shaobo Fang