APE picoEMERALD OPO

picoEmerald inside

The picoEMERALD was especially designed as a light source for CARS- and coherent RAMAN microscopy.

The picoEMERALD combines a picosecond OPO (optical parametric oscillator) and its pump laser in a single integrated housing. Besides the wavelengths of the OPO, the fundamental wavelength of the pump laser at 1064 nm is available to the user as well. The OPO itself is pumped with the frequency doubled wavelength at 532 nm.
The optics modules were optimized by finite element analysis and mechanical stability algorithms (misalignment sensitivity optimization) to obtain maximum passive stability. In addition, the OPO resonator can be actively controlled with the user interface and optimized by software routines.
The picoEMERALD supplies fully automated three temporally and spatially overlapping picosecond pulse trains: the fundamental of the pump laser at a wavelength of 1064 nm, the OPO Signal and the OPO Idler. The wavelength of the OPO Signal is selected via the user terminal and is actively being held at the target wavelength with the use of a built in high resolution spectrometer.
Independent power adjustments for the laser fundamental beam at 1064 nm as well as for the OPO Signal and sensors for spatial and temporal overlap are part of the device. With independent feedback loops, the output power of the laser fundamental and the OPO Signal (with blocked Idler) can be held at a constant user selectable value. The pulses from the laser fundamental and the pulses of the OPO Idler can be independently combined with the pulses of the OPO Signal, or blocked.
Raman vibrational excitation modi have a typical bandwidth of ~ 10 cm^-1, thus requiring excitation pulses of maximally the same bandwidth for best spectroscopic resolution. The picoEMERALD fulfills this condition by delivering nearly transform limited pulses of approx. 7 ps at 1064 nm and 5 ... 6 ps from the OPO. To suppress the non resonant background by Stimulated RAMAN Scattering (SRS) or heterodyne CARS microscopy measurements, an integrated amplitude or phase modulation of the 1064 nm beam up to 10 MHz synchronized to the pulse train is optionally available.

Features

Fully remote-controlled and hands free
Three output wavelengths perfectly overlapped in space and time monitored by sensors
Jitter free pulse generation
Constant power control
Picosecond pulses for best resolution in vibrational spectroscopy
Optional modulation of the 1064 nm-beam for SRS microscopy

Specifications
Tuning ranges
	Signal	720 ... 990 nm¹⁾
	Idler	1150 ... 2030 nm
	Δν Signal - Idler	1350 ... 9000 cm^-1
	Δν Signal - 1064 nm	700 ... 4500 cm^-1
Output power
	Signal (@ 750 ... 990 nm)	> 600 mW
	Idler (@ 1150 ... 1350 nm)	> 500 mW
	Laser fundamental @ 1064 nm	> 750 mW
Repetition rate		80 MHz
Pulse width @ 1064 nm		typ. 7 ps
Pulse width OPO		typ. 5 ... 6 ps
Spectral bandwidth (Signal)		typ. 0.3 ... 0.4 nm
Time bandwidth product (Signal, Idler)		typ. 0.6

^{1) The signal range is limited to 780 ... 990 nm when using "Signal only" or "Signal + 1064" (limitation by the output filter).}