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Mildred S. Dresselhaus

Bio: Mildred S. Dresselhaus is an academic researcher from Massachusetts Institute of Technology. The author has contributed to research in topics: Carbon nanotube & Raman spectroscopy. The author has an hindex of 136, co-authored 762 publications receiving 112525 citations. Previous affiliations of Mildred S. Dresselhaus include University of California, Los Angeles & Universidade Federal de Minas Gerais.


Papers
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Patent
25 Oct 2012
TL;DR: In this paper, a Bi1-xSbx thin film is provided that includes a Dirac-cone with different degrees of anisotropy in their electronic band structure by controlling the stoichiometry, film thickness and growth orientation of the thin film.
Abstract: A Bi1-xSbx thin film is provided that includes a Dirac-cone with different degrees of anisotropy in their electronic band structure by controlling the stoichiometry, film thickness, and growth orientation of the thin film, so as to result in a consistent inverse-effective mass tensor including non-parabolic or linear dispersion relations

2 citations

Journal ArticleDOI
TL;DR: In this article, a thermoelectric transport property study of Bi 1−x Sb x alloy nanowires embedded in a dielectric matrix is presented, where temperature-dependent resistance measurements exhibit nonmonotonic trends as the antimony mole fraction (x) increases.
Abstract: We present here a thermoelectric transport property study of Bi 1−x Sb x alloy nanowires embedded in a dielectric matrix. Temperature-dependent resistance measurements exhibit nonmonotonic trends as the antimony mole fraction (x) increases, and a theoretical model is presented to explain the features that are related to the unusual band structure of Bi 1−x Sb x systems. Seebeck coefficient measurements are performed on nanowires with different diameters and compositions, showing enhanced thermopower over bulk Bi. The magneto-Seebeck coefficient of these nanowires also exhibits an unusual field dependence that is absent in bulk samples.

2 citations

Journal ArticleDOI
TL;DR: The microstructure and electrochemical properties of polyparaphenylene (PPP)-based carbons prepared by the Kovacic and Yamamoto methods have been comparatively studied after heat-treatment up to 3000°C as discussed by the authors.
Abstract: The microstructure and electrochemical properties of polyparaphenylene (PPP)-based carbons prepared by the Kovacic and the Yamamoto methods have been comparatively studied after heat-treatment up to 3000°C. The results obtained by X-ray diffraction can clarify the specific electrochemical properties of PPP-based carbons and graphites.

2 citations

Book ChapterDOI
01 Jan 1988
TL;DR: Ion implantation is an important technique for modifying material properties through the introduction of impurity atoms or the creation of lattice defects in a controlled way as mentioned in this paper, and it is important in the semiconductor industry for making p-n junctions by implanting n-type impurities into p-type host materials.
Abstract: Ion implantation is an important technique for modifying material properties through the introduction of impurity atoms or the creation of lattice defects in a controlled way. The technique is important in the semiconductor industry for making p-n junctions by, for example, implanting n-type impurities into p-type host materials. From a materials science point of view, ion implantation allows essentially any element of the periodic table to be introduced into the near-surface region of essentially any host material, with quantitative control over the depth and composition profile of the impurity by proper choice of ion energy and fluence (i.e., the total number of implanted ions per unit area of sample). Furthermore an important application of ion implantation is in the synthesis of metastable alloys which could not be produced by other means.

2 citations


Cited by
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Journal ArticleDOI
22 Oct 2004-Science
TL;DR: Monocrystalline graphitic 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.
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.

55,532 citations

Journal ArticleDOI
Sumio Iijima1
01 Nov 1991-Nature
TL;DR: Iijima et al. as mentioned in this paper reported the preparation of a new type of finite carbon structure consisting of needle-like tubes, which were produced using an arc-discharge evaporation method similar to that used for fullerene synthesis.
Abstract: THE synthesis of molecular carbon structures in the form of C60 and other fullerenes1 has stimulated intense interest in the structures accessible to graphitic carbon sheets. Here I report the preparation of a new type of finite carbon structure consisting of needle-like tubes. Produced using an arc-discharge evaporation method similar to that used for fullerene synthesis, the needles grow at the negative end of the electrode used for the arc discharge. Electron microscopy reveals that each needle comprises coaxial tubes of graphitic sheets, ranging in number from 2 up to about 50. On each tube the carbon-atom hexagons are arranged in a helical fashion about the needle axis. The helical pitch varies from needle to needle and from tube to tube within a single needle. It appears that this helical structure may aid the growth process. The formation of these needles, ranging from a few to a few tens of nanometres in diameter, suggests that engineering of carbon structures should be possible on scales considerably greater than those relevant to the fullerenes. On 7 November 1991, Sumio Iijima announced in Nature the preparation of nanometre-size, needle-like tubes of carbon — now familiar as 'nanotubes'. Used in microelectronic circuitry and microscopy, and as a tool to test quantum mechanics and model biological systems, nanotubes seem to have unlimited potential.

39,086 citations

Journal ArticleDOI
TL;DR: 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 can now be mimicked and tested in table-top experiments.
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.

35,293 citations

01 May 1993
TL;DR: Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems.
Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

29,323 citations

Journal ArticleDOI
TL;DR: In this paper, the basic theoretical aspects of graphene, a one-atom-thick allotrope of carbon, with unusual two-dimensional Dirac-like electronic excitations, are discussed.
Abstract: This article reviews the basic theoretical aspects of graphene, a one-atom-thick allotrope of carbon, with unusual two-dimensional Dirac-like electronic excitations. The Dirac electrons can be controlled by application of external electric and magnetic fields, or by altering sample geometry and/or topology. The Dirac electrons behave in unusual ways in tunneling, confinement, and the integer quantum Hall effect. The electronic properties of graphene stacks are discussed and vary with stacking order and number of layers. Edge (surface) states in graphene depend on the edge termination (zigzag or armchair) and affect the physical properties of nanoribbons. Different types of disorder modify the Dirac equation leading to unusual spectroscopic and transport properties. The effects of electron-electron and electron-phonon interactions in single layer and multilayer graphene are also presented.

20,824 citations