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Register a new userTrapping of ultra-cold atoms with the magnetic field of vortices in a thin film superconducting micro-structure
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We store and control ultra-cold atoms in a new type of trap using magnetic fields of vortices in a high temperature superconducting micro-structure. This is the first time ultra-cold atoms have been trapped in the field of magnetic flux quanta. We generate the attractive trapping potential for the atoms by combining the magnetic field of a superconductor in the remanent state with external homogeneous magnetic fields. We show the control of crucial atom trap characteristics such as an efficient intrinsic loading mechanism, spatial positioning of the trapped atoms and the vortex density in the superconductor. The measured trap characteristics are in good agreement with our numerical simulations.
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In this chapter we review the field of radio-frequency dressed atom trapping. We emphasise the role of adiabatic potentials and give simple, but generic models of electromagnetic fields that currently produce traps for atoms at microkelvin temperatures and below. The paper aims to be didactic and starts with general descriptions of the essential ingredients of adiabaticity and magnetic resonance. As examples of adiabatic potentials we pay attention to radio-frequency dressing in both the quadrupole trap and the Ioffe-Pritchard trap. We include a description of the effect of different choices of radio-frequency polarisation and orientations or alignment. We describe how the adiabatic potentials, formed from radio-frequency fields, can themselves be probed and manipulated with additional radio-frequency fields including multi-photon-effects. We include a description of time-averaged adiabatic potentials. Practical issues for the construction of radio-frequency adiabatic potentials are addressed including noise, harmonics, and beyond rotating wave approximation effects.
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