| 1. |
- Karch, J., et al.
(författare)
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Terahertz Radiation Driven Chiral Edge Currents in Graphene
- 2011
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Ingår i: Physical Review Letters. - : American Physical Society. - 1079-7114 .- 0031-9007. ; 107:27
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Tidskriftsartikel (refereegranskat)abstract
- We observe photocurrents induced in single-layer graphene samples by illumination of the graphene edges with circularly polarized terahertz radiation at normal incidence. The photocurrent flows along the sample edges and forms a vortex. Its winding direction reverses by switching the light helicity from left to right handed. We demonstrate that the photocurrent stems from the sample edges, which reduce the spatial symmetry and result in an asymmetric scattering of carriers driven by the radiation electric field. The developed theory based on Boltzmann's kinetic equation is in a good agreement with the experiment. We show that the edge photocurrents can be applied for determination of the conductivity type and the momentum scattering time of the charge carriers in the graphene edge vicinity.
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| 2. |
- Drexler, C., et al.
(författare)
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Terahertz radiation induced edge currents in graphene
- 2011
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Ingår i: RMMW-THz 2011 - 36th International Conference on Infrared, Millimeter, and Terahertz Waves. - 9781457705090
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Konferensbidrag (refereegranskat)abstract
- We report on the observation of the terahertz radiation induced edge photogalvanic effect. The directed net electric current is generated in single layer graphene by the irradiation of the samples' edges with linearly or circularly polarized terahertz laser radiation at normal incidence. We show that the directed net electric current stems from the sample edges, which reduce locally the symmetry and result in an asymmetric scattering of carriers driven by the radiation field.
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| 3. |
- Karch, J., et al.
(författare)
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Dynamic Hall Effect Driven by Circularly Polarized Light in a Graphene Layer
- 2010
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Ingår i: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 105:22, s. 227402-
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Tidskriftsartikel (refereegranskat)abstract
- We report the observation of the circular ac Hall effect where the current is solely driven by the crossed ac electric and magnetic fields of circularly polarized radiation. Illuminating an unbiased monolayer sheet of graphene with circularly polarized terahertz radiation at room temperature generates-under oblique incidence-an electric current perpendicular to the plane of incidence, whose sign is reversed by switching the radiation helicity. Alike the classical dc Hall effect, the voltage is caused by crossed E and B fields which are, however rotating with the lights frequency.
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| 4. |
- Bilski, P., et al.
(författare)
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The problems associated with the monitoring of complex workplace radiation fields at European high-energy accelerators and thermonuclear fusion facilities
- 2007
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Ingår i: Radiation Protection Dosimetry. - : Oxford University Press (OUP). - 0144-8420 .- 1742-3406. ; 126:1-4, s. 491-496
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Tidskriftsartikel (refereegranskat)abstract
- The European Commission is funding within its Sixth Framework Programme a three-year project (2005-2007) called CONRAD, COordinated Network for RAdiation Dosimetry. The organisational framework for this project is provided by the European Radiation Dosimetry Group EURADOS. One task within the CONRAD project, Work Package 6 (WP6), was to provide a report outlining research needs and research activities within Europe to develop new and improved methods and techniques for the characterisation of complex radiation fields at workplaces around high-energy accelerators, but also at the next generation of thermonuclear fusion facilities. The paper provides an overview of the report, which will be available as CERN Yellow Report.
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