We introduce and analyze a one-dimensional quantum walk with two time-independent rotations on the coin. We study the influence on the property of quantum walk due to the second rotation on the coin. Based on the asymptotic solution in the long time limit, a ballistic behaviour of this walk is observed. This quantum walk retains the quadratic growth of the variance if the combined operator of t...

In zero magnetic field, conductance measurements of clean one-dimensional (1D) constrictions defined in GaAs/AlGaAs heterostructures show twenty-six quantized ballistic plateaux, as well as a structure close to 0.7(2e 2 /h). In an in-plane magnetic field all the 1D subbands show Zeeman splitting and in the wide channel limit the g-factor is | g |= 0.4, close to that of bulk GaAs. For the last s...

Nonstationary properties of ballistic constrictions N cS ′ S with disordered S ′ S electrodes are analyzed theoretically. Amplitudes of Andreev and normal reflections at the constriction are related to the solutions of a stationary Green function problem in an inhomogeneous S ′ S electrode in a dirty limit. This provides a generalization of the model of Blonder, Tinkham and Klapwijk for a spati...

The calculation of the Kapitza boundary resistance between dissimilar harmonic solids has since long (Little [Can. J. Phys. 37, 334 (1959)]) suffered from a paradox: this resistance erroneously tends to a finite value in the limit of identical solids. We resolve this paradox by calculating temperature differences in the final heat-transporting state, rather than with respect to the initial stat...

Charge transport in semiconducting single-walled nanotubes (SWNTs) with Schottky-barrier contacts has been studied at high bias. We observe nearly symmetric ambipolar transport with electron and hole currents significantly exceeding 25 microA, the reported current limit in metallic SWNTs due to optical phonon emission. Four simple models for the field-dependent velocity (ballistic, current satu...

Diffusive-ballistic heat conduction of finite-length single-walled carbon nanotubes has been studied by means of non-equilibrium molecular dynamics simulations. The length-dependence of thermal conductivity is quantified for a range of nanotube-lengths up to a micrometer at room temperature. A gradual transition from nearly pure ballistic to diffusive-ballistic heat conduction was identified fr...

A battle management system for comprehensive ballistic missile defense must perform with near perfection and extraordinarily reliability. It will be complex to an unprecedented degree, untestable in a realistic environment, and provide minimal time for human intervention. The feasibility of designing and developing such a system (requiring upwards of ten million lines of code) is examined in li...

The terrorist attacks of September 11, 2001 illustrated in graphic terms the vulnerability of the United States to asymmetrical attack. The relative ease with which the nineteen Al Qaeda terrorists hijacked four airplanes and used them as deadly ballistic missiles was inconceivable to the citizens of the world’s only remaining superpower. In an instant, it became painfully clear that despite it...

Amodel is proposed for describing the penetration of a monolithic semi-infinite and finite FRP laminates struck transversely by a rigid projectile with an arbitrary 3-D shape. Relationships for calculating the characteristics of penetration and perforation (ballistic limit velocity, depth of penetration, etc.) are derived. It is showed that some typical problems of optimization of the shape of ...