Time-orbiting-potential chip trap for cold atoms

We present a design for an atom chip trap that uses the time-orbiting potential technique. The offers several advantages compared to other chip-trap methods. It simple crossed-wire pattern on chip, along with rotating bias field. is naturally close spherically symmetric, and it can be modified exactly symmetric in quadratic order of coordinates. Loading from magneto-optical facilitated because positioned arbitrary distance chip. fields provide gradient support against gravity, three-dimensional adiabatically transformed into two-dimensional guide.