A review of X-ray laser development at Rutherford Appleton 
Laboratory

Tallents, G. J.; Abou‐Ali, Y.; Edwards, M. H.; King, Robert; Pert, G.J.; Pestehe, S.J.; Strati, F.; Lewis, Ciaran; Keenan, R.; Topping, S.; Klisnick, A.; Guilbaud, Olivier; Ros, D.; Clarke, R. J.; Notley, M.; Neely, D.

doi:10.1017/s0263034602202074

Cited by 11 publications

(5 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The solid curves in Fig. 3 are f its of the data with the expression from Tallents et al 15 for the variation of the line intensity with plasma length, taking into account gain saturation. The resulting small-signal gain coefficient for the 18.9-nm line is 58 cm 21 , and the gain -length product GL reaches 15.5, a value that corresponds to saturated operation in collisional laser systems.…”

mentioning

confidence: 97%

Saturated high-repetition-rate 189-nm tabletop laser in nickellike molybdenum

et al. 2005

View full text Add to dashboard Cite

We report saturated operation of an 18.9-nm laser at 5-Hz repetition rate. An amplification with a gain -length product GL of 15.5 is obtained in the 4d 1 S 0 4p 1 P 1 laser line of Ni-like Mo in plasmas heated at grazing incidence with ϳ1-J pulses of 8.1-ps duration from a tabletop laser system. Lasing is obtained over a broad range of time delays and pumping conditions. We also measure a GL of 13.5 in the 22.6-nm transition of the same ion. The results are of interest for numerous applications requiring high-repetition-rate lasers at wavelengths below 20 nm. There is great interest in the development of compact saturated high-repetition-rate lasers capable of producing significant average output powers at soft-x-ray wavelengths for applications. Ne-like Ar capillary-discharge-pumped lasers operating at repetition rates of up to 10 Hz have been demonstrated to produce milliwatt average powers at 46.9 nm. 1,2More recently, saturated optical f ield ionization lasers operating in Pd-like Xe at 41.8 nm and in Ni-like Kr at 32.8 nm were obtained by use of 0.33-and 0.76-J pulses, respectively, from a femtosecond 10-Hz pump laser. 3,4 Longitudinal pumping of Mo plasma with short pulses from 10-Hz lasers produced nonsaturated amplification at 18.9 nm in Ni-like Mo, 5,6 a laser line first observed in a small-scale pump system using 80-ps pump pulses. 7Transient collisional electron excitation of targets at normal incidence with 3-10 J of pump energy has produced several saturated lasers in the 12-33-nm range at repetition rates of one shot every several minutes. 8,9 Excitation of a Mo target with 150-fs, 300-mJ pulses impinging at 60 ± from normal incidence resulted in the appearance of the 18.9-and 22.6-nm laser lines of Ni-like Mo. 10 Recently, it was shown that the pumping energy necessary for lasing could be significantly reduced by directing the short pulse onto the target at grazing incidence. 11,12This inherently traveling-wave pumping geometry takes advantage of the refraction of the pump beam to increase the path length of the rays in the gain region of the plasma, thereby increasing the fraction of the pump energy absorbed in that region. A gain -length product of ϳ15 was reported in the 18.9-nm line of Ni-like Mo with 150 mJ of total pumping energy from a 10-Hz laser. 13A normal-incidence 200-ps prepulse was focused into a 15-mm-wide line focus and followed by a 1.5-ps short pulse impinging at a grazing-incidence angle of 14 ± . Lasing was observed to occur over only an extremely narrow ϳ50-ps range of prepulse-to-short-pulse time delays.Herein, we report saturated laser operation in the 18.9-nm line of Ni-like Mo and strong amplif ication at 22.6 nm by use of a 5 -10-Hz tabletop pump laser.Lasing was obtained over a very broad range of time delays. The gain medium was created by the combination of laser pulses generated by an 800-nm tabletop Ti:sapphire laser system with three stages of amplification. A beam splitter directed 20% of the third-stage output to the prepulse arm (120 ps FWHM, 350 mJ), and the re...

show abstract

mentioning

confidence: 97%

Saturated high-repetition-rate 189-nm tabletop laser in nickellike molybdenum

et al. 2005

View full text Add to dashboard Cite

show abstract

“…The CLF also had the scientific, technical and engineering expertise to build specialized systems such as a split field microscope and an optical illumination system based on spherical aberration designed by I. Ross [236] . This delivered near-diffraction-limited straight line foci of aspect ratios up to 1000:1, ideal for pumping long plasma lengths enabling many X-ray Laser Consortium studies [237,238] .…”

Section: X-ray Laser Consortiummentioning

confidence: 99%

A history of high-power laser research and development in the United Kingdom

Danson

White

Barr

et al. 2021

High Pow Laser Sci Eng

View full text Add to dashboard Cite

The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.

show abstract

“…Saturation of the intensity is observed to have an onset at a plasma-column length of approximately 4 mm. A fit of the data with an expression that takes into account gain saturation [23] yields a gain coefficient of 33 cm À1 and a gain-length product of 14.6. The energy of the most intense laser pulses was estimated to be 2:7 J from the CCD counts.…”

Section: à2mentioning

confidence: 99%

Efficient Excitation of Gain-Saturated Sub-9-nm-Wavelength Tabletop Soft-X-Ray Lasers and Lasing Down to 7.36 nm

et al. 2011

View full text Add to dashboard Cite

We have demonstrated the efficient generation of sub-9-nm-wavelength picosecond laser pulses of microjoule energy at 1-Hz repetition rate with a tabletop laser. Gain-saturated lasing was obtained at ¼ 8:85 nm in nickel-like lanthanum ions excited by collisional electron-impact excitation in a precreated plasma column heated by a picosecond optical laser pulse of 4-J energy. Furthermore, isoelectronic scaling along the lanthanide series resulted in lasing at wavelengths as short as ¼ 7:36 nm. Simulations show that the collisionally broadened atomic transitions in these dense plasmas can support the amplification of subpicosecond soft-x-ray laser pulses. DOI: 10.1103/PhysRevX.1.021023 Subject Areas: Photonics, Plasma PhysicsThe high demand for bright soft-x-ray laser (SXRL) pulses greatly exceeds the beam time available at a few single-user free-electron laser facilities [1,2]. This motivates the development of more compact and widely accessible SXRLs for a broad range of experiments in small laboratory settings. Significant progress has been achieved in the past few years in the development of compact plasma-based soft-x-ray lasers [3][4][5][6][7][8][9][10]. However, repetitive operation of tabletop SXRLs has been limited to wavelengths above 10.9 nm [10]. At shorter wavelengths, the large pump energy required has limited the repetition rate to typically one shot per hour [11][12][13][14][15]. Soft-x-ray lasing at sub-10-nm wavelengths in lanthanide ions was first demonstrated using optical lasers of pump energy of several hundred joules [12,13]. Lasing in nickel-like lanthanum at ¼ 8:85 nm was later obtained by using 18-J pulses from a chirped-pulse-amplification (CPA) laser to achieve transient excitation, but with a gain-length product (g Â l ¼ 7:7) that remained insufficient to reach gain saturation [15]. Progress toward saturated lasing in this transition has been recently reported [16,17]. In turn, lasing at ¼ 7:36 nm in nickel-like Sm was initially demonstrated using 130-J pump pulses [12]. Later, gain saturation was reached using a picosecond-duration pump pulse with approximately 40 J of energy added to a prepulse of similar energy [14]. Also recently, the lasing threshold in this line was reached through the use of a total optical pump energy of 36 J [18]. However, the practical realization of highrepetition-rate tabletop lasers at sub-10-nm wavelengths requires obtaining gain-saturated lasing at significantly lower pump energies. We report the generation of gainsaturated picosecond SXRL pulses at ¼ 8:85 nm at 1-Hz repetition rate. The result is obtained by using a picosecond pump pulse with an unprecedentedly low energy of 4 J and a total optical pump energy of 7.5 J, that will make the operation at high-repetition rates possible. Furthermore, using the same pump energy, we observe lasing at wavelengths down to ¼ 7:36 nm in transitions of higher-Z nickel-like lanthanide ions, opening the prospect of practical gain-saturated tabletop lasers at shorter wavelengths. Modeling suggests that these dense-pl...

show abstract

A review of X-ray laser development at Rutherford Appleton Laboratory

Cited by 11 publications

References 22 publications

Saturated high-repetition-rate 189-nm tabletop laser in nickellike molybdenum

Saturated high-repetition-rate 189-nm tabletop laser in nickellike molybdenum

A history of high-power laser research and development in the United Kingdom

Efficient Excitation of Gain-Saturated Sub-9-nm-Wavelength Tabletop Soft-X-Ray Lasers and Lasing Down to 7.36 nm

Contact Info

Product

Resources

About