Optical dipole trap
= Optical dipole trap
A far-detuned <laser> produces an atomic <AC Stark shift> approximately $U=-\operatorname{Re}\alpha(\omega)|E_0|^2/4$. Its spatial gradient creates a conservative dipole force. For a suitable red-detuned ground-state atom, high intensity is an <energy> minimum and can confine several hyperfine states without relying on nonzero permanent magnetic moments. Photon scattering, differential light shifts and intensity noise remain limitations. This atomic use is more specific than a general dielectric-particle <optical trap>.