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831
Diffusion in disordered media
 ADVANCES IN PHYSICS, 51: 1, 187 — 292
, 2002
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Some interesting properties of metals confined in time and nanometer space of different shapes
 Acc. Chem. Res
, 2001
"... The properties of a material depend on the type of motion its electrons can execute, which depends on the space available for them (i.e., on the degree of their spatial confinement). Thus, the properties of each material are characterized by a specific length scale, usually on the nanometer dimensio ..."
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Cited by 47 (1 self)
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The properties of a material depend on the type of motion its electrons can execute, which depends on the space available for them (i.e., on the degree of their spatial confinement). Thus, the properties of each material are characterized by a specific length scale, usually on the nanometer dimension. If the physical size of the material is reduced below this length scale, its properties change and become sensitive to its size and shape. In this Account we describe some of the observed new chemical, optical, and thermal properties of metallic nanocrystals when their size is confined to the nanometer length scale and their dynamical processes are observed on the femto to picosecond time scale. I.
An introduction to computational nano mechanics and materials
 Computer Methods in Applied Mechanics and Engineering 193
, 2004
"... Accepted for publication in Handbook of Theoretical and Computational ..."
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Cited by 41 (10 self)
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Accepted for publication in Handbook of Theoretical and Computational
Some largescale matrix computation problems
, 1996
"... There are numerous applications in physics, statistics and electrical circuit simulation where it is required to bound entries and the trace of the inverse and the determinant of a large sparse matrix. All these computational tasks are related to the central mathematical problem studied in this pape ..."
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Cited by 35 (4 self)
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There are numerous applications in physics, statistics and electrical circuit simulation where it is required to bound entries and the trace of the inverse and the determinant of a large sparse matrix. All these computational tasks are related to the central mathematical problem studied in this paper, namely, bounding the bilinear form uXf(A)v for a given matrix A and vectors u and v, wherefis a given smooth function and is defined on the spectrum of A. We will study a practical numerical algorithm for bounding the bilinear form, where the matrix A is only referenced through matrixvector multiplications. A Monte Carlo method is also presented to efficiently estimate the trace of the inverse and the determinant of a large sparse matrix.
Fundamental transmitting properties of carbon nanotube antennas
 TRANS. ANTENNAS PROPAGATION
, 2005
"... Fundamental properties of dipole transmitting antennas formed by carbon nanotubes are investigated. Since carbon nanotubes can be grown to centimeter lengths, and since they can be metallic, the properties of carbon nanotubes as antenna elements are of fundamental interest. In this paper, dipole c ..."
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Cited by 35 (4 self)
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Fundamental properties of dipole transmitting antennas formed by carbon nanotubes are investigated. Since carbon nanotubes can be grown to centimeter lengths, and since they can be metallic, the properties of carbon nanotubes as antenna elements are of fundamental interest. In this paper, dipole carbon nanotube antennas are investigated via a classical Hallen'stype integral equation, based on a quantum mechanical conductivity. The input impedance, current profile, and efficiency are presented, and the radiation pattern is discussed, as are possible applications.
Size and Temperature Dependence of the Plasmon Absorption of Colloidal Gold Nanoparticles
 J. Phys. Chem. B
, 1999
"... nanoparticles in aqueous solution. The plasmon bandwidth is found to follow the predicted behavior as it increases with decreasing size in the intrinsic size region (mean diameter smaller than 25 nm), and also increases with increasing size in the extrinsic size region (mean diameter larger than 25 ..."
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Cited by 34 (0 self)
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nanoparticles in aqueous solution. The plasmon bandwidth is found to follow the predicted behavior as it increases with decreasing size in the intrinsic size region (mean diameter smaller than 25 nm), and also increases with increasing size in the extrinsic size region (mean diameter larger than 25 nm). Because of this pronounced size effect a homogeneous size distribution and therefore a homogeneous broadening of the plasmon band is concluded for all the prepared gold nanoparticle samples. By applying a simple twolevel model the dephasing time of the coherent plasmon oscillation is calculated and found to be less than 5 fs. Furthermore, the temperature dependence of the plasmon absorption is examined. A small temperature effect is observed. This is consistent with the fact that the dominant electronic dephasing mechanism involves electronelectron interactions rather than electronphonon coupling.
Domain wall theory for ferroelectric hysteresis
 Journal of Intelligent Material Systems and Structures
, 1999
"... This paper addresses the modeling of hysteresis in ferroelectric materials through consideration of domain wall bending and translation. The development is considered in two steps. In the rst step, dielectric constitutive relations are obtained through consideration of Langevin, Ising spin and prefe ..."
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Cited by 33 (23 self)
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This paper addresses the modeling of hysteresis in ferroelectric materials through consideration of domain wall bending and translation. The development is considered in two steps. In the rst step, dielectric constitutive relations are obtained through consideration of Langevin, Ising spin and preferred orientation theory with domain interactions incorporated through mean eld relations. This yields a model for the anhysteretic polarization that occurs in the absence of domain wall pinning. In the second step, hysteresis is incorporated through the consideration of domain wall dynamics and the quanti cation of energy losses due to inherent inclusions or pinning sites within the material. This yields a model analogous to that developed by Jiles and Atherton for ferromagnetic materials. The viability of the model is illustrated through comparison with experimental data from a PMNPTBT actuator operating at a temperature within the ferroelectric regime. i 1
Fractal Renewal Processes Generate 1/f Noise
, 1993
"... f D noise occurs in an impressive variety of physical systems, and numerous complex theories have been proposed to explain it. We construct two relatively simple renewal processes whose power spectral densities vary as 1=f D : 1) a standard renewal point process, with 0 ! D ! 1; and 2) a finite ..."
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Cited by 33 (5 self)
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f D noise occurs in an impressive variety of physical systems, and numerous complex theories have been proposed to explain it. We construct two relatively simple renewal processes whose power spectral densities vary as 1=f D : 1) a standard renewal point process, with 0 ! D ! 1; and 2) a finitevalued alternating renewal process, with 0 ! D ! 2. The resulting event number statistics, coincidence rates, minimal coverings, and autocorrelation functions are shown also to follow powerlaw forms. These fractal characteristics derive from intereventtime probability density functions which themselves decay in a powerlaw fashion. A number of applications are considered: trapping in amorphous semiconductors, electronic burst noise, movement in systems with fractal boundaries, the digital generation of 1=f D noise, and ionic currents in cell membranes. 05.40.+j, 02.50.+s, 72.20.Jv, 72.80.Ng, 87.10.+e Typeset using REVT E X 1 I.
Lattice sums for the Helmholtz equation
 SIAM Review
"... Abstract. A survey of different representations for lattice sums for the Helmholtz equation is given. These sums arise naturally when dealing with wave scattering by periodic structures. One of the main objectives is to show how the various forms depend on the dimension d of the underlying space and ..."
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Cited by 31 (2 self)
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Abstract. A survey of different representations for lattice sums for the Helmholtz equation is given. These sums arise naturally when dealing with wave scattering by periodic structures. One of the main objectives is to show how the various forms depend on the dimension d of the underlying space and the lattice dimension dΛ. Lattice sums are related to, and can be calculated from, the quasiperiodic Green’s function and this object serves as the starting point of the analysis.
Firstprinciples elastic constants for the hcp transition metals Fe, Co, and Re at high pressure.
 Phys. Rev. B
, 1999
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