The Scarlet laser is an ultra-intense, short pulse, laser system at The Ohio State University’s High Energy Density Physics group. Scarlet is a 400 Terawatt (TW) laser with an output of 15 Joules (J), in 40 femtoseconds (fs) at a rate of one shot per minute.
Scarlet Laser specifications:
400 TW System:
- 1021 W/cm2 intensity
- 400 TW peak power
- 800 nanometer wavelength
- 15 Joule per pulse
- 40 femtosecond pulse width
- 5 micron FWHM focal spot size
- 1 shot/minute repetition rate
- Greater than 1010:1 pulse contrast ratio
Laser Diagnostic devices:
- On-shot energy
- SPIDER Single Shot Pulse Width
- On-shot intensity spectrum
- Third-order Cross-Correlator for Pulse Contrast
- On-shot focal spot diagnostic
- Water-cell nanosecond pulse contrast
- Spatial mode cameras
- Spatial chirp diagnostic
Experimental Diagnostic devices:
- Electron/positron magnet based spectrometers
- Thomson parabola ion spectrometer
- Bremsstrahlung x-ray spectrometer (HXBS
- 68 eV XUV imager
- 256 eV XUV imager
- 394 eV XUV imager developed in collaboration with BNL
- Front and rear side HOPG x-ray spectrometer with flat crystals
- Curved HAPG spectrometer and imager
- Cu K-alpha imager based on spherically bent Bragg crystal
- Zr K-alpha imager based on spherically bent Bragg crystal
- Si He-alpha imager based on spherically bent Bragg crystal
- Radiochromic film pack (RCF)
- Single hit CCD spectrometer
- Cherenkov spectrometer
- Scintillator array
- Neutron detector (scintillator based)
- Image plate reader
![Rendering of the Laser Rendering of the Laser](/sites/default/files/styles/50/public/facilities-scarlet-laser-render_0.jpg?itok=RmkHYwnM)
Bringing the laser to the 400 TW level required the addition of a final 3-pass ti:sapp amplifier. This final amplifier is pumped with 50 J of green lasers. Now, the laser will propagate in vacuum to a compressor, which utilizes a pair of diffraction gratings measuring 36 cm and 56 cm in length. After compression, the laser continues, in vacuum, through a pellicle chamber, towards the target chamber. The pellicle chamber serves to isolate the compressor chamber from the target chamber by holding a 4 micron thick pellicle at Brewster angle. Once the beam enters the target chamber it is focused to a 5 micron focal spot which impinges on an engineered and expertly aligned target.
![Pellicle Chamber CAD Drawing Pellicle Chamber CAD Drawing](/sites/default/files/styles/50/public/facilities-cad-pellicle-chamber.jpg?itok=J84qcQsG)
![Target Chamber CAD drawing Target Chamber CAD drawing](/sites/default/files/styles/50/public/facilities-cad-target-chamber.jpg?itok=j1FwR3gr)
![Pellicle-Target Chamber in Place Pellicle-Target Chamber in Place](/sites/default/files/styles/50/public/facilities-pellicle-target-chamber-in-place.jpg?itok=XIyqTCow)
This 15 J, 40 fs pulse laser will fire at full power once per minute and reach intensities at focus of 1021 W/cm2. The resulting laser delivers more power in one shot than the world’s total annual power consumption.