Laser-focused atomic deposition is a technique with which nearly resonant light is used to pattern an atom beam.To solve the problem that the result of laser-cooled atoms cannot be monitored during the 30-min depositing time,we present a three-hole mechanically precollimated aperture apparatus.A 425 nm laser light standing wave is used to focus a beam of chromium atoms to fabricate the nanoscale grating.The period of the grating is 213±0.1 nm,the height is 4 nm and the full width at half miximum is 64±6 nm.
The use of the dipole force on atoms is a new technology that is used to build nanostructures.In this way,a high quality standard nano-grating can be obtained.Based on the semi-classical model,the motion equation is investigated and the trajectories of atoms in double half Gaussian standing wave field are simulated.Compared with the Gaussian standing wave field,the double half Gaussian standing wave can well focus the Cr atoms.In order to obtain this kind of beam,a prism is designed and the experimental result shows that the beam is well generated.
