TOPAS-SHBC-400 combines a second harmonic bandwidth compressor (SHBC) and an optical parametric amplifier (OPA) for the generation of tunable pulses with a spectral bandwidth of 3 – 20 cm^-1 when pumped by femtosecond pulses with a spectral bandwidth of 150 – 500 cm^-1. The device is designed to be pumped by a fundamental harmonic of a femtosecond Ti:Sapphire laser and covers a wavelength range from 480 to 2400 nm. Optional frequency mixers extend the tuning range down to 240 nm and up to 10 μm.

Specifications Notes

TOPAS-SHBC-400 specifications are given for the following SHBC output parameters:

400 nm wavelength
0.5 mJ pulse energy

Note 1: Specifications depend on SHBC output wavelength. If it differs from the value above, contact sales@lightcon.com.

Note 2: TOPAS-SHBC-400 output pulse energy scales linearly in 0.5 – 2 mJ range, provided the device is installed and optimized for particular pump energy. The device has to be re-optimized if the pump energy changes more than 10% from the installation value.

Pump Laser Requirements

Model	TOPAS-SHBC-400
Pump wavelength	770 – 830 nm
Pump pulse energy	0.3 – 5 mJ
Pump pulse duration (FWHM)	20 – 200 fs
Repetition rate	< 25 kHz
Maximum pump power	25 W ¹⁾
Polarization	Linear, horizontal
Spectral bandwidth	< 1.2× transform limit
Pulse-to-pulse energy stability	< 1% RMS deviation ²⁾
Pulse duration stability	< 1% pulse-to-pulse ³⁾
Pulse front tilt	< 10% of pulse duration
Pulse contrast	< 1 : 20
Beam quality (M²)	< 1.3 ⁴⁾
Beam astigmatism	< 0.15 ⁵⁾
Beam spatial profile	Gaussian – Super Gaussian
Intensity modulation	< 15%, no hotspots ⁶⁾
Beam pointing stability	< 10 μrad ⁷⁾
Beam divergence	< 1.2× diffraction limit
Beam height from optical table	125 – 185 mm
Beam diameter (1/e²)	< 8 mm ⁸⁾

Contact sales@lightcon.com for higher pump power options.
Normalized to average pulse energy, NRMSD.
Normalized to average pulse duration, NRMSD.
M² specification valid for Gaussian beam.
Normalized astigmatism – difference of the waist positions, divided by Rayleigh length.
Normalized to Gaussian or Super-Gaussian fits, NRMSD.
NRMSD, full angle.
Optional external telescope can be ordered for the beam size 8 – 28 mm.

SHBC Output

Model	SHBC
Output wavelength	385 – 415 nm
Conversion efficiency	> 25% (20 – 70 fs), > 35% (70 – 200 fs)
Spectral bandwidth	< 10 cm^-1
Time-bandwidth product	< 1.2
Polarization	Horizontal
Pulse-to-pulse energy stability	< 3% RMS deviation ¹⁾

Normalized to average pulse energy, NRMSD.

TOPAS-SHBC-400 Output

Model	TOPAS-SHBC-400
Tuning range	480 – 800 nm (Signal) ¹⁾800 – 2400 nm (Idler)
Conversion efficiency at peak (Signal and Idler combined)	> 20% ²⁾
Spectral bandwidth	< 20 cm^-1 @ 500 – 730 nm, 870 – 2400 nm
Time-bandwidth product	< 1.2
Polarization	Vertical (Signal) Horizontal (Idler)
Pulse-to-pulse energy stability	< 6% RMS deviation ³⁾ @ 500 – 700 nm, 900 – 2000 nm

Some energy and spectrum modulation possible in the 730 – 870 nm range.
Assuming 0.5 mJ, 400 nm pump from SHBC. Conversion efficiency at peak of > 20%.
Normalized to average pulse energy, NRMSD.

UV extensions (240 – 480 nm)

Extension	SHS	SHI
Tuning range	240 – 400 nm	400 – 480 nm
Conversion efficiency at peak	> 4% ¹⁾	> 3% ¹⁾
Spectral bandwidth	< 20 cm^-1	< 20 cm^-1
Polarization	Horizontal	Vertical