Laser-diode-tuned chromium-atom trapping and fabrication with atom-optics technology

We developed a laser-beam-controlled atom-manipulation system to deposit nanometric structure of atoms on a substrate. Atom beam of chromium is thermally evaporated and collimated with Doppler cooling technique using frequency-tuned laser diode. The gradient force is exerted on atoms by a standing wave over the substrate, and atoms are trapped in a low potential region of the standing wave. Consequently, a series of lines are formed on the substrate with the same periodicity to the standing wave. We present the analysis of trajectories of atoms in the light force potential to find conditions of the laser power, the sign and the degree of the detuning of the laser frequency from the resonance frequency of the atom, to reduce the width of the structure.