Journal ArticleDOI
Analysis of Gaussian beam propagation and diffraction by inhomogeneous wave tracking
S. Choudhary,L.B. Felsen +1 more
- Vol. 62, Iss: 11, pp 1530-1541
TLDR
In this paper, a previously developed asymptotic theory for high-frequency propagation and scattering of such waves is applied to the propagation of paraxial Gaussian beams in free space, to beams in a lens-like medium with parabolic variation of the refractive index and to beam reflection by a cylindrical obstacle.Abstract:
Inhomogeneous waves behave locally like A(r) exp[ikS(r)], where A and S are spatially dependent complex amplitude and phase functions, and k is the (large) free-space wavenumber. A previously developed asymptotic theory for high-frequency propagation and scattering of such waves is here applied to the propagation and scattering of paraxial Gaussian beams. Attention is given to Gaussian beams in free space, to beams in a lens-like medium with parabolic variation of the refractive index, and to beam reflection by a cylindrical obstacle. In the latter instance, the obstacle size may be comparable to the incident beamwidth, thereby introducing substantial distortion into the reflected beam. The results obtained from the asymptotic theory are verified by comparison with rigorously derived solutions, thereby confirming the validity of the theory, which can also be applied to more general medium and obstacle configurations.read more
Citations
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Techniques for High-Frequency Problems
TL;DR: In this article, the authors employ approximations based on high-frequency techniques for performing an efficient analysis of electromagnetic radiating systems that are large in terms of the wavelength, which is not the case for most of the existing techniques.
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Gaussian beam and pulsed-beam dynamics: complex-source and complex-spectrum formulations within and beyond paraxial asymptotics.
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References
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Journal ArticleDOI
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Journal ArticleDOI
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