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Electron spin coherence near room temperature in magnetic quantum dots.

ABSTRACT: We report on an example of confined magnetic ions with long spin coherence near room temperature. This was achieved by confining single Mn(2+) spins in colloidal semiconductor quantum dots (QDs) and by dispersing the QDs in a proton-spin free matrix. The controlled suppression of Mn-Mn interactions and minimization of Mn-nuclear spin dipolar interactions result in unprecedentedly long phase memory (TM ~ 8 ?s) and spin-lattice relaxation (T1 ~ 10 ms) time constants for Mn(2+) ions at T = 4.5 K, and in electron spin coherence observable near room temperature (TM ~ 1 ?s).

SUBMITTER: Moro F

PROVIDER: S-EPMC4455149 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Electron spin coherence near room temperature in magnetic quantum dots.

Moro Fabrizio F Turyanska Lyudmila L Wilman James J Fielding Alistair J AJ Fay Michael W MW Granwehr Josef J Patanè Amalia A

Scientific reports 20150604

We report on an example of confined magnetic ions with long spin coherence near room temperature. This was achieved by confining single Mn(2+) spins in colloidal semiconductor quantum dots (QDs) and by dispersing the QDs in a proton-spin free matrix. The controlled suppression of Mn-Mn interactions and minimization of Mn-nuclear spin dipolar interactions result in unprecedentedly long phase memory (TM ~ 8 μs) and spin-lattice relaxation (T1 ~ 10 ms) time constants for Mn(2+) ions at T = 4.5 K, a ...[more]

PMID: 26040432

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