And here it is, modelled using LTSpice. It is the same circuit as the classic simple precision rectifier (set to pass the negative half-sine), but with the non-inverting input of the op-amp connected ...

The basis of a solid-state diode laser is, of course, the diode. Laser diodes can have different emission wavelength—most of them have between 405 nm to 808 nm. The diodes usually have TO3, TO5, TO9, ...