80 research outputs found
Improved solar cell contacting techniques Final report
Aluminum, nickel, and copper contacted solar cells using ion beam sputterin
Use of Switching Q in the Design of FET Microwave Switches
The application of FET's as microwave switches suitable for monolithic integration is analyzed by means of a procedure based on the switching Q of Kurokawa and Schlosser. Factors determining the Q of FET's for switching are discussed
Use of Switching Q in the Design of FET Microwave Switches
The application of FET's as microwave switches suitable for monolithic integration is analyzed by means of a procedure based on the switching Q of Kurokawa and Schlosser. Factors determining the Q of FET's for switching are discussed
Site-bond representation and self-duality for totalistic probabilistic cellular automata
We study the one-dimensional two-state totalistic probabilistic cellular
automata (TPCA) having an absorbing state with long-range interactions, which
can be considered as a natural extension of the Domany-Kinzel model. We
establish the conditions for existence of a site-bond representation and
self-dual property. Moreover we present an expression of a set-to-set
connectedness between two sets, a matrix expression for a condition of the
self-duality, and a convergence theorem for the TPCA.Comment: 11 pages, minor corrections, journal reference adde
Absorption problems for quantum walks in one dimension
This paper treats absorption problems for the one-dimensional quantum walk
determined by a 2 times 2 unitary matrix U on a state space {0,1,...,N} where N
is finite or infinite by using a new path integral approach based on an
orthonormal basis P, Q, R and S of the vector space of complex 2 times 2
matrices. Our method studied here is a natural extension of the approach in the
classical random walk.Comment: 15 pages, small corrections, journal reference adde
Lattice Kinetics of Diffusion-Limited Coalescence and Annihilation with Sources
We study the 1D kinetics of diffusion-limited coalescence and annihilation
with back reactions and different kinds of particle input. By considering the
changes in occupation and parity of a given interval, we derive sets of
hierarchical equations from which exact expressions for the lattice coverage
and the particle concentration can be obtained. We compare the mean-field
approximation and the continuum approximation to the exact solutions and we
discuss their regime of validity.Comment: 24 pages and 3 eps figures, Revtex, accepted for publication in J.
Phys.
Precise Critical Exponents for the Basic Contact Process
We calculated some of the critical exponents of the directed percolation
universality class through exact numerical diagonalisations of the master
operator of the one-dimensional basic contact process. Perusal of the power
method together with finite-size scaling allowed us to achieve a high degree of
accuracy in our estimates with relatively little computational effort. A simple
reasoning leading to the appropriate choice of the microscopic time scale for
time-dependent simulations of Markov chains within the so called quantum chain
formulation is discussed. Our approach is applicable to any stochastic process
with a finite number of absorbing states.Comment: LaTeX 2.09, 9 pages, 1 figur
A sufficient criterion for integrability of stochastic many-body dynamics and quantum spin chains
We propose a dynamical matrix product ansatz describing the stochastic
dynamics of two species of particles with excluded-volume interaction and the
quantum mechanics of the associated quantum spin chains respectively. Analyzing
consistency of the time-dependent algebra which is obtained from the action of
the corresponding Markov generator, we obtain sufficient conditions on the
hopping rates for identifing the integrable models. From the dynamical algebra
we construct the quadratic algebra of Zamolodchikov type, associativity of
which is a Yang Baxter equation. The Bethe ansatz equations for the spectra are
obtained directly from the dynamical matrix product ansatz.Comment: 19 pages Late
Directed Ising type dynamic preroughening transition in one dimensional interfaces
We present a realization of directed Ising (DI) type dynamic absorbing state
phase transitions in the context of one-dimensional interfaces, such as the
relaxation of a step on a vicinal surface. Under the restriction that particle
deposition and evaporation can only take place near existing kinks, the
interface relaxes into one of three steady states: rough, perfectly ordered
flat (OF) without kinks, or disordered flat (DOF) with randomly placed kinks
but in perfect up-down alternating order. A DI type dynamic preroughening
transition takes place between the OF and DOF phases. At this critical point
the asymptotic time evolution is controlled not only by the DI exponents but
also by the initial condition. Information about the correlations in the
initial state persists and changes the critical exponents.Comment: 12 pages, 10 figure
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