LE-0600 Diode pumped Nd:YAG Laser

A. LE-0600 Diode pumped Nd:YAG Laser with hemi-spherical cavity

B. LE-0600 Diode pumped Nd:YAG Laser with concentric cavity

Optical pumping in conjunction with Nd:YAG lasers is of particular interest, because these have become widely accepted for industrial use, along with the CO2 laser. The laser-active material which, in the case of the Nd:YAG laser, is excited by optical pumping, consists of Neodymium atoms that are accommodated in a transparent YAG host crystal (Yttrium Aluminum Garnet).
Whereas up to a few years ago Nd:YAG lasers were always excited using discharge lamps, optical pumping with laser diodes is becoming more and more significant. This is because laser diodes are available economically and they emit narrow band light at high optical powers, which matches the energy levels of the Nd:YAG crystal. The advantage over the discharge lamp is that the emission of laser diodes is nearly completely absorbed by the Nd:YAG, whereas the very wide spectral emission of discharge lamps is absorbed to only a small extent only.
The four level system is explained, a theoretical analysis of the Nd:YAG laser is performed, and a rate equation model derived. The steady state solution is presented, and the dynamic situation considered to investigate spiking.
Besides the set-up with a hemi-spherical cavity (Fig. A.), a concentric cavity (Fig. B.) can also be arranged. In this case, the Nd:YAG rod has only an anti-reflection coating and is placed in the center of the cavity.
The kit contains all components necessary to assemble a diode pumped Nd:YAG laser - a 1 W diode (LD) with driver and Peltier controller, collimating (CO) and focusing optics (FL), Nd:YAG crystal (ND), laser mirror (M1), a photodiode detector (PD) with filer (FI) and all necessary mounts etc.
The stability criterion of the resonator are verified experimentally. The dependence of the pump wavelength on diode temperature and drive current are proven, and the absorption spectrum of Nd:YAG derived. By using a few additional modules, this basic set-up can be up-graded to LE-0700 „Frequency Doubling with KTP“ or LE-0800 „Generation of short pulses“. Furthermore the components for the oscillation at 1.3 µm including frequency doubling to "red" or an active or passive Q-switch are available as options.