Thomas W. Ebbesen

Bio: Thomas W. Ebbesen is an academic researcher from University of Strasbourg. The author has contributed to research in topics: Surface plasmon & Plasmon. The author has an hindex of 99, co-authored 305 publications receiving 70789 citations. Previous affiliations of Thomas W. Ebbesen include NEC & Aalborg University.

Surface plasmon subwavelength optics

Abstract: Surface plasmons are waves that propagate along the surface of a conductor. By altering the structure of a metal's surface, the properties of surface plasmons--in particular their interaction with light--can be tailored, which offers the potential for developing new types of photonic device. This could lead to miniaturized photonic circuits with length scales that are much smaller than those currently achieved. Surface plasmons are being explored for their potential in subwavelength optics, data storage, light generation, microscopy and bio-photonics.

Extraordinary optical transmission through sub-wavelength hole arrays

Abstract: The desire to use and control photons in a manner analogous to the control of electrons in solids has inspired great interest in such topics as the localization of light, microcavity quantum electrodynamics and near-field optics1,2,3,4,5,6. A fundamental constraint in manipulating light is the extremely low transmittivity of apertures smaller than the wavelength of the incident photon. While exploring the optical properties of submicrometre cylindrical cavities in metallic films, we have found that arrays of such holes display highly unusual zero-order transmission spectra (where the incident and detected light are collinear) at wavelengths larger than the array period, beyond which no diffraction occurs. In particular, sharp peaks in transmission are observed at wavelengths as large as ten times the diameter of the cylinders. At these maxima the transmission efficiency can exceed unity (when normalized to the area of the holes), which is orders of magnitude greater than predicted by standard aperture theory. Our experiments provide evidence that these unusual optical properties are due to the coupling of light with plasmons — electronic excitations — on the surface of the periodically patterned metal film. Measurements of transmission as a function of the incident light angle result in a photonic band diagram. These findings may find application in novel photonic devices.

Exceptionally high Young's modulus observed for individual carbon nanotubes

Abstract: CARBON nanotubes are predicted to have interesting mechanical properties—in particular, high stiffness and axial strength—as a result of their seamless cylindrical graphitic structure1–5. Their mechanical properties have so far eluded direct measurement, however, because of the very small dimensions of nanotubes. Here we estimate the Young's modulus of isolated nanotubes by measuring, in the transmission electron microscope, the amplitude of their intrinsic thermal vibrations. We find that carbon nanotubes have exceptionally high Young's moduli, in the terapascal (TPa) range. Their high stiffness, coupled with their low density, implies that nanotubes might be useful as nanoscale fibres in strong, lightweight composite materials.

Large-scale synthesis of carbon nanotubes

Abstract: INTEREST in carbon fibres1,2 has been stimulated greatly by the recent discovery of hollow graphitic tubules of nanometre dimensions3. There has been much speculation about the properties and potential application of these nanotubes4–8. Theoretical studies predict that their electronic properties will depend on their diameter and degree of helicity4,5. Experimental tests of these ideas has been hampered, however, by the lack of macroscopic quantities of the material. Here we report the synthesis of graphitic nanotubes in gram quantities. We use a variant of the standard arc-discharge technique for fullerene synthesis under a helium atmosphere. Under certain conditions, a carbonaceous deposit forms on one of the graphite rods, consisting of a macroscopic (diameter of about 5 mm) cylinder in which the core comprises pure nanotubes and nanoscale particles in high yield. The purity and yield depend sensitively on the gas pressure in the reaction vessel. Preliminary measurements of the conductivity of the bulk nanotube material indicate a conductivity of about 100 S cm–11.

Electrical-Conductivity of Individual Carbon Nanotubes

Abstract: THE interest in carbon nanotubes has been greatly stimulated by theoretical predictions that their electronic properties are strongly modulated by small structural variations1–8. In particular, the diameter and the helicity of carbon atoms in the nanotube shell are believed to determine whether the nanotube is metallic or a semiconductor. Because of the enormous technical challenge of making measurements on individual nanotubes, however, experimental studies have been limited mainly to bulk measurements9, which indicate only that a fraction of the nanotubes are metallic or narrow-band semiconductors10. Recently, measurements of the magneto-conductance of a single multi-shell nanotube in a two-probe configuration showed that the transport is characterized by disorder and localization phenomena11. To avoid possible ambiguities due to poor sample contacts, four-probe measurements are needed. Here we report four-probe measurements on single nanotubes made by lithographic deposition of tungsten leads across the tubes. We find that each multi-shell nanotube has unique conductivity properties. Both metallic and non-metallic behaviour are observed, as well as abrupt jumps in conductivity as the temperature is varied. The differences between the electrical properties of different nanotubes are far greater than expected. Our results suggest that differences in geometry play a profound part in determining the electronic behaviour.

Electric Field Effect in Atomically Thin Carbon Films

Abstract: We describe monocrystalline graphitic films, which are a few atoms thick but are nonetheless stable under ambient conditions, metallic, and of remarkably high quality. The films are found to be a two-dimensional semimetal with a tiny overlap between valence and conductance bands, and they exhibit a strong ambipolar electric field effect such that electrons and holes in concentrations up to 10 13 per square centimeter and with room-temperature mobilities of ∼10,000 square centimeters per volt-second can be induced by applying gate voltage.

The rise of graphene

Abstract: Graphene is a rapidly rising star on the horizon of materials science and condensed-matter physics. This strictly two-dimensional material exhibits exceptionally high crystal and electronic quality, and, despite its short history, has already revealed a cornucopia of new physics and potential applications, which are briefly discussed here. Whereas one can be certain of the realness of applications only when commercial products appear, graphene no longer requires any further proof of its importance in terms of fundamental physics. Owing to its unusual electronic spectrum, graphene has led to the emergence of a new paradigm of 'relativistic' condensed-matter physics, where quantum relativistic phenomena, some of which are unobservable in high-energy physics, can now be mimicked and tested in table-top experiments. More generally, graphene represents a conceptually new class of materials that are only one atom thick, and, on this basis, offers new inroads into low-dimensional physics that has never ceased to surprise and continues to provide a fertile ground for applications.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Measurement of the Elastic Properties and Intrinsic Strength of Monolayer Graphene

Abstract: We measured the elastic properties and intrinsic breaking strength of free-standing monolayer graphene membranes by nanoindentation in an atomic force microscope. The force-displacement behavior is interpreted within a framework of nonlinear elastic stress-strain response, and yields second- and third-order elastic stiffnesses of 340 newtons per meter (N m(-1)) and -690 Nm(-1), respectively. The breaking strength is 42 N m(-1) and represents the intrinsic strength of a defect-free sheet. These quantities correspond to a Young's modulus of E = 1.0 terapascals, third-order elastic stiffness of D = -2.0 terapascals, and intrinsic strength of sigma(int) = 130 gigapascals for bulk graphite. These experiments establish graphene as the strongest material ever measured, and show that atomically perfect nanoscale materials can be mechanically tested to deformations well beyond the linear regime.