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Ultralong Spin Lifetime in Light Alkali Atom Doped Graphene.

ABSTRACT: Today's great challenges of energy and informational technologies are addressed with a singular compound, Li- and Na-doped few-layer graphene. All that is impossible for graphite (homogeneous and high-level Na doping) and unstable for single-layer graphene works very well for this structure. The transformation of the Raman G line to a Fano line shape and the emergence of strong, metallic-like electron spin resonance (ESR) modes attest the high level of graphene doping in liquid ammonia for both kinds of alkali atoms. The spin-relaxation time in our materials, deduced from the ESR line width, is 6-8 ns, which is comparable to the longest values found in spin-transport experiments on ultrahigh-mobility graphene flakes. This could qualify our material as a promising candidate in spintronics devices. On the other hand, the successful sodium doping, this being a highly abundant metal, could be an encouraging alternative to lithium batteries.

SUBMITTER: Markus BG

PROVIDER: S-EPMC7315639 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Ultralong Spin Lifetime in Light Alkali Atom Doped Graphene.

Márkus B G BG Szirmai P P Edelthalhammer K F KF Eckerlein P P Hirsch A A Hauke F F Nemes N M NM Chacón-Torres Julio C JC Náfrádi B B Forró L L Pichler T T Simon F F

ACS nano 20200610 6

Today's great challenges of energy and informational technologies are addressed with a singular compound, Li- and Na-doped few-layer graphene. All that is impossible for graphite (homogeneous and high-level Na doping) and unstable for single-layer graphene works very well for this structure. The transformation of the Raman G line to a Fano line shape and the emergence of strong, metallic-like electron spin resonance (ESR) modes attest the high level of graphene doping in liquid ammonia for both ...[more]

PMID: 32484657

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