In cooperation with the Iranian Nuclear Society

Document Type : Research Paper

Authors

Photonics and Quantum Technologies Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.Box: 14395-836, Tehran - Iran

Abstract

In this study, the amplification of Ti: sapphire laser pulses in a regenerative amplifier with Z geometric arrangement has been demonstrated based on chirped pulse amplification method. Two pocket cells were used to transfer the seed pulses to the amplifier cavity and extract the amplified pulses. Build up time of the amplified pulses according to the energy of the pump laser has been studied, and the dynamic evolution of the pulses inside the amplifier cavity has been investigated.  The pulse duration of the generated pulses inside the cavity without seed pulses is about 80 ns, and the buildup time is 38 ns. The 2 mJ amplified femtosecond laser pulses at a repetition rate of 10 Hz are obtained after 17 round trips using pump energy of 15 mJ at 532 nm. The amplified laser wavelength is 800 nm with 30 nm spectral bandwidth, which is 30 nm narrower than the oscillator bandwidth. The amplification efficiency relative to the pump energy is obtained at about 13%, and the amplification coefficient in this scheme reached 106.

Keywords

1. H. Kiriyama, et al., High-Contrast, High-Intensity Petawatt-Class Laser and Applications, IEEE J. Select. Top. Quantum Electron., 21, 232–249 (2015).
 
2. T. Asavei, et al., Materials in Extreme Environments for Energy, Accelerators and Space Applicaions at ELI-NP.Rom. Rep. Phys., 68, S275–S347 (2016).
 
3. D. Strickland, G. Mourou, Compression of Amplified Chirped Optical Pulses, Opt. Commun., 56, 219-221 (1985).
 
4. D.E. Spence, P.N. Kean, W. Sibbett, 60-fsec pulse generation from a self-mode-locked Ti:sapphire laser, Opt. Lett., 16, 42–44 (1991).
 
5. H. Kiriyama, et al., Petawatt Femtosecond Laser Pulses from Titanium-Doped Sapphire Crystal, Crystals, 10, 783 (2020).
 
6. J.W. Yoon, et al., Achieving the laser intensity of
5.5×1022 W/cm2 with a wavefront-corrected multi-PW laser
, Opt. Express, 27, 20412–20420 (2019).
 
7. F. Hajiesmaeilbaigi, A. Azima, Ultrashort pulse generation by self-mode-locked Ti:sapphire laser without apertures and with low pumping powers, Canadian Journal of Phusics, 76(6), 495-499 (1998).
 
8. T.J. Yu, et al., Generation of high-contrast, 30 fs, 1.5PW laser pulses from chirped-pulse amplification Ti:sapphire laser, Opt. Express, 20, 10807–10815, (2012).
 
9. H. Kiriyama, et al., High temporal and spatial quality petawatt class Ti:sapphire chirped pulse amplification laser system, Opt. Lett., 35, 1497-1499 (2010).
 
10. M. Cerchez, et al., ARCTURUS laser: a versatile high-contrast,high-power multi-beam laser system, High Power Laser Science and Engineering, 7(37), 11 (2019).
 
11. J. Jeong, et al., Modeling and Analysis of High Power Ti:sapphire Laser  amplifiers–A, Review Appl. Sci., 9, 2396 ( 2019).
 
12. S.J. Hwang, et al., Femtosecond Laser Pulse Distortion in Ti:sapphire Multipass Amplifier by Atomic Phase Shifts, J. Korean Phys. Soc., 71, 652–656 (2017).
 
13. Wei Zhang, et al., Efficient amplification of a femtosecond Ti:sapphire laser with a ring regenerative amplifier, Applied Optics, 52, 7 (2013).
 
14. J. Easter, et al., Stable Long-Cavity Regenerative Amplifier with 10-11 ASE Contrast, Conference Paper. June (2007). DOI: 10.1109/CLEO.2007.4453573. Source: IEEE Xplore.
 
15. J.C. Diels, Ultrashort Laser Pulse Phenomena: Fundamentals, Techniques, and Applications on a Femtosecond Time Scale, 2nd ed. (Elsevier/Academic Press Amsterdam, the Netherlands, 2006).
 
16. O. Svelto, Principles of lasers, 5th ed. (Springer, 2010, Chapter 8).