Fast Incomplete Decoherence of Nuclear Spins in Quantum Hall Ferromagnet

Physical Review B (Impact Factor: 3.77). 11/2000; DOI:10.1103/PhysRevB.64.193306
Source: arXiv

ABSTRACT A scenario of quantum computing process based on the manipulation of a large number of nuclear spins in Quantum Hall (QH) ferromagnet is presented. It is found that vacuum quantum fluctuations in the QH ferromagnetic ground state at filling factor $\nu =1$, associated with the virtual excitations of spin waves, lead to fast incomplete decoherence of the nuclear spins. A fundamental upper bound on the length of the computer memory is set by this fluctuation effect.

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