Cold Atoms and Creation of New States of Matter: Bose-Einstein Condensates, Kapitza States, and '2D Magnetic Hydrogen Atoms'

TL;DR

This paper reports the creation of Bose-Einstein condensates with sodium atoms, explores wave guides for atomic matter waves, and introduces a hydrogenic spectrum of bound states using supersymmetry.

Contribution

It presents new methods for trapping and manipulating cold atoms, including a '4D' magnetic trap and novel wave guide structures, along with theoretical insights into atomic spectra.

Findings

Successful creation of Bose-Einstein condensates with 2 million sodium atoms.

Demonstration of distinct expansion modes of condensate and thermal cloud.

Derivation of a hydrogenic spectrum of bound states via supersymmetry.

Abstract

We have succeded in creating Bose-Einstein condensates with 2 million sodium atoms in a '4D' magnetic trap. We show the dynamic formation of a condensate as evaporative cooling proceeds. We also present a series of trap-release pictures clearly showing the distinctly different modes of expansion of condensate and thermal cloud. We further give two examples of wave guides for atomic de Broglie matter waves. One structure, the Kapitza wave guide, uses the interaction between an electrically polarizable atom and a charged wire. For stably bound orbits, a dynamical stabilization with time dependent potentials is necessary. This system, which can be tuned freely between classical and quantum regimes, shows chaotic behavior in the classical limit. The static counterpart of this wave guide leads to the introduction of the 'angular momentum quantum ladder' . The second wave guide structure is based upon the interaction between a current carrying wire and the magnetic dipole moment of an atom. A hydrogenic spectrum of bound states is derived through the concept of supersymmetry.