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Geometric spin echo under zero field.

ABSTRACT: Spin echo is a fundamental tool for quantum registers and biomedical imaging. It is believed that a strong magnetic field is needed for the spin echo to provide long memory and high resolution, since a degenerate spin cannot be controlled or addressed under a zero magnetic field. While a degenerate spin is never subject to dynamic control, it is still subject to geometric control. Here we show the spin echo of a degenerate spin subsystem, which is geometrically controlled via a mediating state split by the crystal field, in a nitrogen vacancy centre in diamond. The demonstration reveals that the degenerate spin is protected by inherent symmetry breaking called zero-field splitting. The geometric spin echo under zero field provides an ideal way to maintain the coherence without any dynamics, thus opening the way to pseudo-static quantum random access memory and non-invasive biosensors.

SUBMITTER: Sekiguchi Y

PROVIDER: S-EPMC4874036 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Geometric spin echo under zero field.

Sekiguchi Yuhei Y Komura Yusuke Y Mishima Shota S Tanaka Touta T Niikura Naeko N Kosaka Hideo H

Nature communications 20160519

Spin echo is a fundamental tool for quantum registers and biomedical imaging. It is believed that a strong magnetic field is needed for the spin echo to provide long memory and high resolution, since a degenerate spin cannot be controlled or addressed under a zero magnetic field. While a degenerate spin is never subject to dynamic control, it is still subject to geometric control. Here we show the spin echo of a degenerate spin subsystem, which is geometrically controlled via a mediating state s ...[more]

PMID: 27193936

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