In cooperation with the Iranian Nuclear Society

Optimization of pump laser conditions for production of maximum gain of Ne-like Ge soft x-ray laser

Document Type : Research Paper

Authors

1 Hazrat-e Masoumeh University, P.O.BOX: 37115-145, Qom, Iran.

2 Plasma and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.BOX: 14399-51113, Tehran, Iran.

Abstract
Laser produced plasma can be used as the sources of soft X-ray laser. The ability to control the laser quality and its gain coefficient by controlling laser and plasma’s parameters is one of the advantages of this method. In this study, a pump pulse assistant along with a pre-pulse is irradiated on a geranium target as the plasma active medium, thenthe gain of soft X-ray laser at wavelength 19.6 nm is calculated. In order to analyze the effect of laser parameters such as intensity, pulse length, and time delay between two pulses, MED103 hydrodynamic code has been used. The simulation results show that there is optimal pulse duration for the pre-pulse as well as the main pump pulse to achieve the maximum gain of soft X-ray laser. In addition, according to the results, by increasing the pre-pulse intensity the amount of soft X-ray laser gain initially increases and then decreases, while by enhancing the main pulse intensity, it keeps increasing. Also, the optimal spatiotemporal regions of the soft X-ray laser gain for different time delays of two pulses are given.

Highlights

1.    H. Daido, Review of soft x-ray laser researches and developmentsRep. Prog. Phys. 65, 1513-1576 (2002).

 

2.  S. Suckewer and P. Jaegle, X-Ray laser: past, present, and futureLaser Phys. Lett. 6, 411–436 (2009).

 

3.   G. J. Tallents, The physics of soft x-ray lasers pumped by electron collisions in laser plasmasJ. Phys D: Appl. Phys. 36, R259 (2003).

 

4.    B. Rus, et al. Multi-millijoule, deeply saturated x-ray laser at 21.2 nm for applications in plasma physicsPlasma Phys. Control. Fusion 44, B207–B223 (2002).

 

5.  T. ‌Mocek et al. Beam properties of a deeply saturated, half-cavity zinc soft-x-ray laserJ. Opt. Soc. Am. B. 20, 1386 (2003).

 

6.   G. Ghani-Moghadam, A. H. Farahbod, Investigation of self-filtering unstable resonator for soft X-ray lasers, Opt. Commun. 371, 154 (2016).

 

7.     G. Ghani Moghadam and A. H. Farahbod, General formula for calculation of amplified spontaneous emission intensityOpt. Quant. Electron. 48, 227 (2016).

 

8.     D. L. Matthews et al. Demonstration of a soft x-ray amplifierPhys. Rev. Lett. 54, 110 (1985).

 

9.     P. Jaegle et al. High gain‐production efficiency and large brightness X‐UV laser at PalaiseauAIP Conference Proceedings 332, 25 (1995).

 

10.  A. Carillon et al. Saturated and near-diffraction-limited operation of an XUV laser at 23.6 nmPhys. Rev. Lett. 68, 2917 (1992).

 

11.  J. A. Koch et al. Observation of gain-narrowing and saturation behavior in Se x-ray laser line profilesPhys. Rev. Lett. 68, 3291 (1992).

 

12.  J. Nilsen et al. Prepulse technique for producing low-Z Ne-like x-ray lasersPhys. Rev. A 48, 4682 (1993).

 

13.   G. F. Cairns et al. Using low and high prepulses to enhance the J= 0− 1 transition at 19.6 nm in the Ne-like germanium XUV laserOpt. Commun. 123, 777 (1996).

 

14.   J. Nilsen and J. C. Moreno, Nearly Monochromatic Lasing at 182 Å in Neonlike SeleniumPhys. Rev. Lett. 74, 3376 (1995).

 

15.  A. Behjat et al. The effects of multi-pulse irradiation on X-ray laser mediaOpt. Commun. 135, 49 (1997).

 

16.  E. Oliva et al. Hydrodynamic study of plasma amplifiers for soft-x-ray lasers: A transition in hydrodynamic behavior for plasma columns with widths ranging from 20 μm to 2 mmPhys. Rev. E. 82, 056408, (2010).

 

17.   J. Dunn et al. Demonstration of x-ray amplification in transient gain nickel-like palladium schemePhys. Rev. Lett. 80, 2825 (1998).

 

 

18.   J. Dunn et al. Demonstration of transient gain x-ray lasers near 20 nm for nickellike yttrium, zirconium, niobium, and molybdenumOpt. Lett. 24, 101 (1999).

 

19.  M. P. Kalachnikov et al. Saturated operation of a transient collisional x-ray laserPhys. Rev. A 57, 4778 (1998).

 

20.  Y. L. Li et al. Saturated tabletop x-ray laser system at 19 nmJ. Opt. Soc. Am. B 17, 1098 (2000).

 

21.  K. A. Janulewicz et al. Influence of pump pulse parameters on the collisionally pumped germanium X-ray laser in the transient gain regimeOpt. Commun. 168, 183-193 (1999).

 

22.   P. B. Holden et al. A computational investigation of the neon-like germanium collisionally pumped laserJ. Phys. B: At. Mol. Opt. Phys. 27, 341-367 (1994).

 

23.  S. B. Healy et al. Transient high gains at 196 Å produced by picosecond pulse heating of a preformed germanium plasmaOpt. Commun. 132, 442-448 (1996).

 

24.   P. J. Warwick et al. Observation of high transient gain in the germanium x-ray laser at 19.6 nmJ. Opt. Soc. Am. B. 15, 6, 1808-1814 (1998).

 

25.  S. Eliezer, The Interaction of High-Power Lasers with Plasmas, (IOP Publishing Ltd, Philadelphia, 2002).

 

26. P. Gibbon, short pulse laser interactions with matter: An introduction, (Imperical College Press, London, 2005).

 

27.  A. Djaoui and S.J. Rose, Calculation of the time-dependent excitation and ionization in a laser-produced plasma, J. Phys B: At. Mol. Opt. Phys. 25, 2745-2762 (1992).

 

28. A. Djaoui, A user guide for the laser-plasma simulation code: MED103PAL-TR-96-099 (1996).

 

29.   Y. J. Li, X. Lu, J. Zhang, Effects of delay time on transient Ni-like x-ray lasersPhys. Rev. E. 66, 046501, (2002).

 

30.   X. Lu, Y. J. Li, J. Zhang, Transient characteristics of a neon-like x-ray laser at 19.6 nmPhysics Of Plasmas, 9, 4, 1412-1415 (2002).

 

31.  X. Lu, Y. J. Li, J. Zhang, Optimization of Drive Pulse Configuration for a High-Gain Transient X-Ray Laser at 19.6 nmCHIN. PHYS. LETT. 18, 10, 1353 (2001).

 

32.  D. Alessi et al. High repetition rate operation of saturated tabletop soft x-ray lasers in transitions of neon-like ions near 30 nmOpt. Express, ‌13, 2093 (2005).

 

33. D. Alessi et al. Efficient Excitation of Gain-Saturated Sub-9-nm-Wavelength Tabletop Soft-X-Ray Lasers and Lasing Down to 7.36 nmPhys. Rev. X. 1, 2, 021023 (2011).

 

34.  G. Ghani Moghadam et al. in: 7th conference on engineering and physics of plasma, (Shahrood University of Technology, Shahrood, Iran, 2019) (In Persian).

 

35. X. Lu et al. Numerical optimization of a picosecond pulse driven Ni-like Nb x-ray laser at 20.3 nmPhysics Of Plasmas, 10, 7, 2978 (2003).

 

 

Keywords


1.    H. Daido, Review of soft x-ray laser researches and developments, Rep. Prog. Phys. 65, 1513-1576 (2002).
 
2.  S. Suckewer and P. Jaegle, X-Ray laser: past, present, and future, Laser Phys. Lett. 6, 411–436 (2009).
 
3.   G. J. Tallents, The physics of soft x-ray lasers pumped by electron collisions in laser plasmas, J. Phys D: Appl. Phys. 36, R259 (2003).
 
4.    B. Rus, et al. Multi-millijoule, deeply saturated x-ray laser at 21.2 nm for applications in plasma physics, Plasma Phys. Control. Fusion 44, B207–B223 (2002).
 
5.  T. ‌Mocek et al. Beam properties of a deeply saturated, half-cavity zinc soft-x-ray laser, J. Opt. Soc. Am. B. 20, 1386 (2003).
 
6.   G. Ghani-Moghadam, A. H. Farahbod, Investigation of self-filtering unstable resonator for soft X-ray lasers, Opt. Commun. 371, 154 (2016).
 
7.     G. Ghani Moghadam and A. H. Farahbod, General formula for calculation of amplified spontaneous emission intensity, Opt. Quant. Electron. 48, 227 (2016).
 
8.     D. L. Matthews et al. Demonstration of a soft x-ray amplifier, Phys. Rev. Lett. 54, 110 (1985).
 
9.     P. Jaegle et al. High gain‐production efficiency and large brightness X‐UV laser at Palaiseau, AIP Conference Proceedings 332, 25 (1995).
 
10.  A. Carillon et al. Saturated and near-diffraction-limited operation of an XUV laser at 23.6 nm, Phys. Rev. Lett. 68, 2917 (1992).
 
11.  J. A. Koch et al. Observation of gain-narrowing and saturation behavior in Se x-ray laser line profiles, Phys. Rev. Lett. 68, 3291 (1992).
 
14.   J. Nilsen and J. C. Moreno, Nearly Monochromatic Lasing at 182 Å in Neonlike Selenium, Phys. Rev. Lett. 74, 3376 (1995).
 
15.  A. Behjat et al. The effects of multi-pulse irradiation on X-ray laser media, Opt. Commun. 135, 49 (1997).
 
16.  E. Oliva et al. Hydrodynamic study of plasma amplifiers for soft-x-ray lasers: A transition in hydrodynamic behavior for plasma columns with widths ranging from 20 μm to 2 mm, Phys. Rev. E. 82, 056408, (2010).
 
17.   J. Dunn et al. Demonstration of x-ray amplification in transient gain nickel-like palladium scheme, Phys. Rev. Lett. 80, 2825 (1998).
 
 
18.   J. Dunn et al. Demonstration of transient gain x-ray lasers near 20 nm for nickellike yttrium, zirconium, niobium, and molybdenum, Opt. Lett. 24, 101 (1999).
 
19.  M. P. Kalachnikov et al. Saturated operation of a transient collisional x-ray laser, Phys. Rev. A 57, 4778 (1998).
 
20.  Y. L. Li et al. Saturated tabletop x-ray laser system at 19 nm, J. Opt. Soc. Am. B 17, 1098 (2000).
 
21.  K. A. Janulewicz et al. Influence of pump pulse parameters on the collisionally pumped germanium X-ray laser in the transient gain regime, Opt. Commun. 168, 183-193 (1999).
 
22.   P. B. Holden et al. A computational investigation of the neon-like germanium collisionally pumped laser, J. Phys. B: At. Mol. Opt. Phys. 27, 341-367 (1994).
 
23.  S. B. Healy et al. Transient high gains at 196 Å produced by picosecond pulse heating of a preformed germanium plasma, Opt. Commun. 132, 442-448 (1996).
 
24.   P. J. Warwick et al. Observation of high transient gain in the germanium x-ray laser at 19.6 nm, J. Opt. Soc. Am. B. 15, 6, 1808-1814 (1998).
 
25.  S. Eliezer, The Interaction of High-Power Lasers with Plasmas, (IOP Publishing Ltd, Philadelphia, 2002).
 
26. P. Gibbon, short pulse laser interactions with matter: An introduction, (Imperical College Press, London, 2005).
 
27.  A. Djaoui and S.J. Rose, Calculation of the time-dependent excitation and ionization in a laser-produced plasma, J. Phys B: At. Mol. Opt. Phys. 25, 2745-2762 (1992).
 
28. A. Djaoui, A user guide for the laser-plasma simulation code: MED103, PAL-TR-96-099 (1996).
 
29.   Y. J. Li, X. Lu, J. Zhang, Effects of delay time on transient Ni-like x-ray lasers, Phys. Rev. E. 66, 046501, (2002).
 
30.   X. Lu, Y. J. Li, J. Zhang, Transient characteristics of a neon-like x-ray laser at 19.6 nm, Physics Of Plasmas, 9, 4, 1412-1415 (2002).
 
31.  X. Lu, Y. J. Li, J. Zhang, Optimization of Drive Pulse Configuration for a High-Gain Transient X-Ray Laser at 19.6 nm, CHIN. PHYS. LETT. 18, 10, 1353 (2001).
 
32.  D. Alessi et al. High repetition rate operation of saturated tabletop soft x-ray lasers in transitions of neon-like ions near 30 nm, Opt. Express, ‌13, 2093 (2005).
 
33. D. Alessi et al. Efficient Excitation of Gain-Saturated Sub-9-nm-Wavelength Tabletop Soft-X-Ray Lasers and Lasing Down to 7.36 nm, Phys. Rev. X. 1, 2, 021023 (2011).
 
34.  G. Ghani Moghadam et al. in: 7th conference on engineering and physics of plasma, (Shahrood University of Technology, Shahrood, Iran, 2019) (In Persian).
 
35. X. Lu et al. Numerical optimization of a picosecond pulse driven Ni-like Nb x-ray laser at 20.3 nm, Physics Of Plasmas, 10, 7, 2978 (2003).