Quantum Teleportation and Quantum Memory in the Same Experiment

Tuesday, March 18, 2008 | 20:19

An important step for future quantum technologies:

[A]n unknown quantum state of a photonic qubit is transferred into quantum memory via teleportation and is stored by two clusters of rubidium atoms. Each cluster contains approximately one million atoms, collected by a magneto-optical trap. The teleported photonic qubit can be stored in memory and read out up to eight microseconds (millionths of a second) before the state is lost. […]

The quantum states carried by the photonic qubits are encoded in the photons' polarization, or the alignment of the photons' emitted electric fields. Each rubidium cluster encodes the information as a collective spin state over all of the electrons in the cluster. Like other unchangeable properties like mass and charge, spin, or angular momentum, is an intrinsic characteristic of an electron. #

The very short storage time and the low teleportation probability are problems that remain to be solved.