English
Related papers

Related papers: Simple approach for high-contrast optical imaging …

200 papers

We show that it is possible to prepare and identify ultra--thin sheets of graphene on crystalline substrates such as SrTiO$_3$, TiO$_2$, Al$_2$O$_3$ and CaF$_2$ by standard techniques (mechanical exfoliation, optical and atomic force…

Materials Science · Physics 2009-11-06 S. Akcoeltekin , M. El Kharrazi , B. Koehler , A. Lorke , M. Schleberger

We investigate graphene and graphene layers on different substrates by monochromatic and white-light confocal Rayleigh scattering microscopy. The image contrast depends sensitively on the dielectric properties of the sample as well as the…

Materials Science · Physics 2008-01-07 C. Casiraghi , A. Hartschuh , E. Lidorikis , H. Qian , H. Harutyunyan , T. Gokus , K. S. Novoselov , A. C. Ferrari

We report a new method for quantitative estimation of graphene layer thicknesses using high contrast imaging of graphene films on insulating substrates with a scanning electron microscope. By detecting the attenuation of secondary electrons…

Mesoscale and Nanoscale Physics · Physics 2012-03-28 Vidya Kochat , Atindra Nath Pal , Sneha E. S. , Arjun B. S. , Anshita Gairola , S. A. Shivashankar , Srinivasan Raghavan , Arindam Ghosh

We study the optical contrast for single and multilayer graphene deposited on a Au/SiO2/Si substrate. Our results prove that optical microscopy allows for easy and quick localization, identification and counting of graphene layers.…

Mesoscale and Nanoscale Physics · Physics 2012-11-07 Igor Wlasny , Pawel Dabrowski , Zbigniew Klusek

The visibility of graphene sheets on different types of substrates has been investigated both theoretically and experimentally. Although single layer graphene is observable on various types of dielectrics under an optical microscope, it is…

Materials Science · Physics 2009-12-29 Guoquan Teo , Haomin Wang , Yihong Wu , Jun Zhang , Zaibing Guo , Zhenhua Ni , Zexiang Shen

A friction based method is proposed for obtaining graphite layers. Freestanding thin structures of graphite containing several layers of graphene are obtained by rubbing a graphite rod on the surfaces of NaCl substrate and then dissolving…

Materials Science · Physics 2014-11-26 Manuel Mailian , Kamran ul Hasan , Aram Mailian

Exfoliated graphene monolayers are identified by optical inspection. In order to improve the monolayer detection, we investigate the angle dependence of the optical contrast of graphene on a 90nm SiO$_2$/Si substrate. We observe a…

Mesoscale and Nanoscale Physics · Physics 2009-10-14 Victor Yu , Michael Hilke

Graphene and graphene-based materials exhibit exceptional optical and electrical properties with great promise for novel applications in light detection. However, several challenges prevent the full exploitation of these properties in…

Materials Science · Physics 2018-09-20 Adolfo De Sanctis , Jake D. Mehew , Monica F. Craciun , Saverio Russo

While silicon has dominated solid-state electronics for more than four decades, a variety of new materials have been introduced into photonics to expand the accessible wavelength range and to improve the performance of photonic devices. For…

Mesoscale and Nanoscale Physics · Physics 2010-09-24 Thomas Mueller , Fengnian Xia , Phaedon Avouris

Gold is widely used as the substrate material in many graphene devices, due to its superior optoelectronic properties and chemical stability. However, there has been little experimental investigation on the optical contrast of graphene…

Optical reflection microscopy is one of the main imaging tools to visualize graphene microstructures. Here is reported a novel method that employs refractive index optimization in an optical reflection microscope, which greatly improves the…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 H. Gonçalves , L. Alves , C. Moura , M. Belsley , T. Stauber , P. Schellenberg

A simple analysis is performed for the absorption properties of graphene; sandwiched between two media. For a proper choice of media and graphene doping/gating one can approach 50-100% absorption in the GHz-THz range for the one atom thick…

Optics · Physics 2012-01-17 S. P. Apell , G. W. Hanson , C. Hägglund

It was demonstrated that optical modulation together with simultaneous terahertz (THz) imaging application enables an increase in contrast by an order of magnitude illustrating hence the technique as convenient contactless tool for…

Imaging ellipsometry studies of graphene on SiO2/Si and crystalline GaAs are presented. We demonstrate that imaging ellipsometry is a powerful tool to detect and characterize graphene on any flat substrate. Variable angle spectroscopic…

Graphene is of increasing interest for optoelectronic applications exploiting light detection, light emission and light modulation. Intrinsically light matter interaction in graphene is of a broadband type. However by integrating graphene…

Single-layer graphene exhibits exceptional mechanical properties attractive for optomechanics: it combines low mass density, large tensile modulus, and low bending stiffness. However, at visible wavelengths, graphene absorbs weakly and…

Optics · Physics 2014-06-10 S. Hossein Mousavi , Peter T. Rakich , Zheng Wang

We demonstrate greatly enhanced light absorption by monolayer graphene over a broad spectral range, from visible to near infrared, based on the attenuated total reflection. In the experiment, graphene is sandwiched between two dielectric…

Optics · Physics 2013-10-01 Wangshi Zhao , Kaifeng Shi , Zhaolin Lu

Implementing new materials as alternative to silicon for application in photonic devices has been the center of attention in the scientific community. Two-Dimensional (2D) materials have shown a great capacity to be next alternative to…

Monolayer graphene absorbs 2.3 percent of the incident visible light. This 'small' absorption has been used to emphasize the visual transparency of graphene, but it in fact means that multilayer graphene absorbs a sizable fraction of…

Graphene has many unique properties that make it an ideal material for fundamental studies as well as for potential applications. Here we review the recent results on the Raman spectroscopy and imaging of graphene. Raman spectroscopy and…

Materials Science · Physics 2008-10-17 Zhen hua Ni , Ying ying Wang , Ting Yu , Ze xiang Shen
‹ Prev 1 2 3 10 Next ›