Quantum bits with molecules

Photonics.com reports that researchers at the Max Planck Institute have developed a novel method of trapping molecules in a lattice of overlapping laser beams and keeping them there.

The work was achieved by physicists at the Max Planck Institute of Quantum Optics in Garching, and the resulting shape of the optical lattice resembles a stack of egg cartons, with exactly two atoms placed into the each well of the carton. By applying a magnetic field, these atom pairs are associated to molecules. The work is reported in the Sept. 24 edition of the journal Nature Physics.

Researchers created the optical lattice by intersecting several laser beams and transferred a very cold gas of rubidium atoms, also called a Bose-Einstein condensate, into the lattice.
The laser lattice looks like a stack of egg cartons with the wells representing locations where the rubidium atoms tend to settle.

The depth of the lattice sites depends on laser intensity. At low laser
intensities, the atoms can move almost freely in the optical lattice
and move from site to site. With increasing laser intensities, the
wells become deeper and deeper and at some point the atoms cannot
escape from the well in which they find themselves — they are trapped
and localized. The resulting highly ordered state is called a Mott
insulator state. Changing the overall atom number in the lattice, the
physicists were able to create a situation with exactly two atoms per
site in the center of the lattice.

Continue reading Quantum bits with molecules