Pump-Probe Spectroscopy & Rotational-Anisotropy Second-Harmonic Generation
Femtosecond Laser and Amplifiers
From Spectra-Physics, we utilize the Spirit HE as a high-power femtosecond laser in combination with two Spirit-NOPA amplifiers. The Spirit HE is a class IV, femtosecond laser with a wavelength of 1040 nm, an output power of 16-30 W, and a pulse energy of 120 μJ. The Spirit-NOPAs are our non-collinear optical parametric amplifiers with a repetition rate of 4.3 MHz, pump power of 70 W, tunable wavelength of 650-900 nm for signal and 1200-2500 nm for idler, and pulse compression of 70 and 100 fs for the signal and idler respectively. These power the Rotational-Anisotropic Second-Harmonic Generation (RA-SHG) as well as the Pump-Probe Spectroscopic experiments.
Cryostation
The Cryostation s50 is a closed-cycle optical cryostat with the ability to control the pressure and temperature parameters of a sample environment. This allows the temperature of the sample to 3.6K with a temperature stability of <20mK. It takes roughly 10 hours and 75mW of power to cool down to 4.2K and able to reach pressures as low as mTorr.
Photon Detector
The detection device used in the RA-SHG experiment. This camera is capable of single photon senstivity.
Frequency-Resolved Optical Gating (FROG)
This experiment allows us to measure the phase of the electric field in the frequency domain of ultrashort laser pulses (femtosecond).