Described herein are electromagnetic traps or tweezers. Desired results
are achieved by combining two recently developed techniques, 3D negative
refraction flat lenses (3DNRFLs) and optical tweezers. The very unique
advantages of using 3DNRFLs for electromagnetic traps have been
demonstrated. Super-resolution and short focal distance of the flat lens
result in a highly focused and strongly convergent beam, which is a key
requirement for a stable and accurate electromagnetic trap. The
translation symmetry of 3DNRFL provides translation-invariance for
imaging, which allows an electromagnetic trap to be translated without
moving the lens, and permits a trap array by using multiple sources with
a single lens.