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9: Plane Waves I

  • Page ID
    22852
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    The use of phasors to describe the propagation of plane waves through space.

    • 9.1: Introduction to Plane Waves
      This page explores electric and magnetic fields from an oscillating dipole, using complex notation for energy density calculations and the Poynting vector. It elaborates on electromagnetic plane waves derived from Maxwell's equations, emphasizing the orthogonality of electric and magnetic fields, and discusses average energy densities and energy transport.
    • 9.2: Phasors
      It is very convenient to represent sinusoidal functions i.e. sines and cosines, by complex exponential functions when dealing with linear differential equations such as Maxwell’s equations.
    • 9.3: Elliptically Polarized Plane Waves
      This page explains the superposition of two plane waves of the same frequency but varying electric field orientations and phase shifts. It covers four cases of polarization: in phase results in linear polarization, 90° out of phase creates right-hand elliptical polarization, 270° yields left-hand elliptical polarization, and a 45° phase shift causes right-hand elliptical polarization with non-aligned axes.
    • 9.4: Gaussian Light Beams
      This page covers the theory of unbounded plane waves and their application in describing finite radiation beams, particularly Gaussian beams. It addresses the complex radius of curvature and its implications for beam propagation, detailing how electric fields change with distance and defining key concepts like the Rayleigh range.

    Thumbnail: The wavefronts of a plane wave traveling in 3-space. (Public Domain; Quibik via Wikipedia)


    This page titled 9: Plane Waves I is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by John F. Cochran and Bretislav Heinrich via source content that was edited to the style and standards of the LibreTexts platform.