I already showed the vacuum system from my grad school days. This is the laser system that drove it. Slowing and trapping a thermal beam of atoms and then creating a new cold beam requires several lasers at different frequencies.

This first picture is a diode laser system, obviously home-built; this pre-dates any sort of commercially available system by several years, and perhaps a decade. On the far left are the electrical connections and the on/off switch. Power is needed for the laser, a piezoelectric transducer stack and the thermoelectic cooler, and a signal from a thermistor is fed back for coarse temperature tuning/stabilization of the wavelength. The diode is mounted in the thin rectangular block and has a collimating lens mounted in the thicker one; as I recall the lens position was adjusted with an external jig and then glued down.

Light leaves the diode and hits the grating, reflecting off to the bottom, but the grating is blazed — the lines are angled, and in this position one of the diffraction orders is reflected back into the laser, which forces the laser to operate at that frequency. Thus, by changing the angle slightly, the wavelength can be tuned over some small range, perhaps a few nanometers. The grating is mounted on a small kinematic mount, and this obscures a gap between two parts of the mount. At the lower right you can see the gap where the piezo stack is, and at the upper left, near the screw, is the pivot point.

The entire block is mounted on a thermoelectric cooler to stabilize the temperature. Laser diodes are coarsely temperature-tunable, so the temperature is chosen to get you close to the desired wavelength (780.24 nm for Rb-85). When operating, this would be covered with a plexiglass housing to act as a thermal barrier and a baffle for air currents, and on later designs contained a tray for a desiccant to help prevent condensation on the cold laser.

Here is the table, with a couple of lasers in the foreground. Light goes out of the side of the boxes and hits the turning mirrors; some of the light is picked off and sent into the spectroscopy cells visible just past the lasers (the one on the left is closer) This ensured the lasers were on resonance.

This is the whole laser table, showing the vacuum system on the right. Much of the equipment is on shelves above the optical table, and this design ensured the attraction of shorter personnel to the lab, as might be predicted by Murphy’s law.

The blue boxes on the center-line of the table are fast photodiodes; we used a beat between lasers to generate a locking signal for those not locked to the spectroscopy signals, and could tune the other lasers several MHz away using this technique. This allowed us to tune the trapping laser beams such that the trap was not stationary in the lab frame. The atoms would feel a force to eject them from the atomic funnel, and the lasers would become equal due to the Doppler shift, once they atoms were moving at the right speed.