Growth of large aperture LBO crystal applied in high power OPCPA schemes

13.4 fs, 0.1 Hz OPCPA Front End for the 100 PW-Class Laser Facility

“…Besides, the chromatic expanders will be used to replace the current expanders to optimize the space-time characterization after the compressor, which are essential for an ultrabroadband laser system to increase the actual focal-spot intensity [26]. At present, the crystal growth technology makes it possible to obtain an LBO crystal with size ~200 mm [23]. Therefore, it could support an output energy above 200 J.…”

“…The gain bandwidths of three crystals at 925 nm phasematching signal wavelength are shown in Figure 2 by solving the coupled wave equations that describe the nonlinear amplification process. Compared with BBO and DKDP (D = 80%), LBO features the moderate nonlinear coefficient (0.79 pm/V), the availability of large size at tens of millimeters [22,23], the smallest walk-off angle (0.47 deg), and the broadband gain spectrum (202 nm, full width at half maximum, FWHM) around 925 nm central wavelength. These features make LBO the excellent nonlinear gain medium for OPCPA.…”

A Review of Optical Parametric Amplification at the Vulcan Laser Facility

“…Naturally, over the past twenty years, technology and knowledge has improved substantially: improved crystal availability [12,13]; spectral shaping and phase control techniques [14][15][16]; compression from large, high-quality gratings; and high-energy nanosecond pumping availability have all contributed to a dramatic improvement in peak pulse intensities.…”

“…Recently, the drive to high-peak-power OPCPA is being simulated and developed in various facilities allowing 10s PW, 100s PW, and even EWs [31][32][33][34][35][36][37][38]. While there is growing demand for scaling LBO crystals [13,39,40], this is currently only possible with the largest available crystals: deuterated Potassium Dihydrogen Phosphate (DKDP), which was first found to be a promising OPCPA candidate in 2005 [41], harbouring broadband amplification from frequency-doubled Nedodymium-doped Yttrium Lithium Fluoride (Nd:YLF) lasers [42]. There has also been a growing interest in Petawatt-scaling using Yttrium Calcium Oxoborate (YCOB) [37,43], however these are not typical due to the limited number of suppliers.…”