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Thermoelectric effects in graphene at high bias current and under microwave irradiation.

ABSTRACT: We use a split top gate to induce doping of opposite signs in different parts of a graphene field-effect transistor, thereby effectively forming a graphene thermocouple. The thermocouple is sensitive to the electronic temperature in graphene, which can be several hundred kelvin higher than the ambient one at sufficiently high bias current. Combined with the high thermoelectric power of graphene, this allows for i) simple measurements of the electronic temperature and ii) building thermoelectric radiation detectors. A simple prototype graphene thermoelectric detector shows a temperature-independent optical responsivity of around 400?V/W at 94?GHz at temperatures of 4-50?K.

SUBMITTER: Skoblin G

PROVIDER: S-EPMC5686182 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Thermoelectric effects in graphene at high bias current and under microwave irradiation.

Skoblin Grigory G Sun Jie J Yurgens August A

Scientific reports 20171114 1

We use a split top gate to induce doping of opposite signs in different parts of a graphene field-effect transistor, thereby effectively forming a graphene thermocouple. The thermocouple is sensitive to the electronic temperature in graphene, which can be several hundred kelvin higher than the ambient one at sufficiently high bias current. Combined with the high thermoelectric power of graphene, this allows for i) simple measurements of the electronic temperature and ii) building thermoelectric ...[more]

PMID: 29138495

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