Robust storage of a qubit in a three-atom system

Seminar

Three spin-1/2 half atoms have joint states with j=3/2 and j=1/2, with two kinds of j=1/2 states. This duplication permits the encoding of a qubit in rotationally invariant states, which are completely insensitive to magnetic stray fields that affect all atoms in the same way. For realistic experimental parameters, storage with very high fidelity is possible for hours. A sequence of single-qubit and two-qubit gates can be used for the encoding, and the reversed sequence for the decoding. The over-all fidelity of encoding, storage, and decoding appears to be limited by the achievable gate fidelity.

Back to list