14,579 research outputs found
Scattering of magnetic edge states
We consider a charged particle following the boundary of a two-dimensional
domain because a homogeneous magnetic field is applied. We develop the basic
scattering theory for the corresponding quantum mechanical edge states. The
scattering phase attains a limit for large magnetic fields which we interpret
in terms of classical trajectories.Comment: 34 pages, 2 figure
Analysis and optimization of an omnidirectional direction-finding system
System determines the direction of arrival of an electromagnetic wave with the direction information in a readily usable form. It presents a relatively small physical structure and does not require mechanical positioning
The heat kernel expansion for the electromagnetic field in a cavity
We derive the first six coefficients of the heat kernel expansion for the
electromagnetic field in a cavity by relating it to the expansion for the
Laplace operator acting on forms. As an application we verify that the
electromagnetic Casimir energy is finite.Comment: 12 page
A general resonance theory based on Mourre's inequality
We study the perturbation of bound states embedded in the continuous spectrum
which are unstable by the Fermi Golden Rule. The approach to resonance theory
based on spectral deformation is extended to a more general class of quantum
systems characterized by Mourre's inequality and smoothness of the resolvent.
Within the framework of perturbation theory it is still possible to give a
definite meaning to the notion of complex resonance energies and of
corresponding metastable states. The main result is a quasi-exponential decay
estimate up to a controlled error of higher order in perturbation theory.Comment: 17 page
A study of antenna and radio frequency tracking system Final summary report, 1 Feb. 1963 - 30 Nov. 1965
Phase stability of very low frequency radio signal propagation, electronically scanned tracking antenna array, and inverted rf tracking syste
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