Scientists at Caltech have developed an approach for quantum storage that could help pave the way for the development of large-scale optical quantum networks.
The new system relies on nuclear spins oscillating collectively as a spin wave. This collective oscillation effectively chains up several atoms to store information.
The study utilizes a qubit made from an ion of ytterbium (Yb), a rare earth element also used in lasers. The team embedded the ion in a transparent crystal of yttrium orthovanadate (YVO4) and manipulated its quantum states via a combination of optical and microwave fields. The team then used the Yb qubit to control the nuclear spin states of multiple surrounding vanadium atoms in the crystal.
This new technique to utilize entangled nuclear spins as a quantum memory was inspired by methods used in Nuclear Magnetic Resonance (NMR).
A unique feature of this system is the pre-determined placement of vanadium atoms around the ytterbium qubit as prescribed by the crystal lattice. Every qubit the team measured had an identical memory register, meaning it would store the same information. (Phys.org)
The paper has been published in the journal Nature.
