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Updated: Jul 6, 2026
11:42
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Fine structure constant defines visual transparency of graphene
R R Nair1, P Blake, A N Grigorenko
1Manchester Centre for Mesoscience and Nanotechnology, University of Manchester, M13 9PL Manchester, UK.
Science (New York, N.Y.)
|April 5, 2008
Summary
Graphene
Area of Science:
- Condensed matter physics
- Quantum electrodynamics
Background:
- Few phenomena in condensed matter physics depend solely on fundamental constants.
- Observing such phenomena typically requires specialized equipment and conditions.
Purpose of the Study:
- To demonstrate that graphene's opacity is determined exclusively by the fine structure constant.
- To highlight a material property defined by fundamental physics rather than material specifics.
Main Methods:
- Theoretical analysis of graphene's interaction with light.
- Experimental measurement of light absorption in suspended graphene.
Main Results:
- Graphene's opacity is solely defined by the fine structure constant (α).
- Suspended graphene absorbs a significant fraction (2.3%) of incident white light.
- This absorption is attributed to graphene's unique electronic structure.
Conclusions:
- Graphene exhibits a fundamental optical property linked to quantum electrodynamics.
- The material's one-atom thickness does not preclude a notable interaction with light.
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