Beam Me Up Ion Traps

As will be spreading through the mainstream news shortly, I’m sure, Nature has two papers out today demonstrating the teleportation of the internal states of trapped ions. Both the NIST and Innsbruck groups have, using fairly different ion trap systems, succeeded in deterministic teleportation of the internal states of the ions. Woot! Woot! Not only are both of these experiements gorgeous, they are sure the sign of much more interesting protocols to be implemented in the near furuture (or, well, the experimentalist’s version of the near furture.) This is the first demonstration of deterministic teleportation of massive qubit systems (there has been a continuous quantum variable deterministic teleportation experiment done using light.)
A few stats.
Ions
NIST: 9Be+
Innsbruck: 40Ca+
Fidelitity
NIST: 76% to 80%
Innsbruck: 73% to 76%
Distance teleported
NIST: 100s of micrometers (?)
Innsbruck: 10 micrometers
Qubit teleported
NIST: Hyperfine ground states: F=1,m=-1 and F=2,m=-2
Innsbruck: ground state S_1/2 (m_J=-1/2) and metastable state D_5/2(m_J=-1/2)
The main difference between these two experiments is in how they achieve individual addressing. The NIST group has these really neat traps which allow you to move the ions into different sets of trapped ions and then address them spatially. The Innsbruck group uses some neat tricks that allow the internal states to guide which qubits they are coupling their laser light to.
It’s experiments like these that make me even more of an optimist about quantum computing (are we all supposed to use the work reaganist instead of optimist now?) Sure we’ve seen teleportation before. But, especially in the NIST experiment, not in such a way that it is clear that it is just the beginning of a long line of rockin bigger and better experiments (ion traps rock, man!)