Modes, electromagnetic transverse electric

In a rectangular cavity, electromagnetic waves are classified as transverse electric (TE) or transverse magnetic (TM) modes. AU the field combinations can be obtained by the superposition of TE and TM modes. TE modes are defined as the waves that have no electric field component in a defined propagation direction. In this discussion, the propagation direction is assumed to be the f-direction. Similarly, TM modes have no magnetic field component in the f - direction. By assuming a cavity with dimensions, a X b X d in the x-,y-, and z-directions, respectively, the frequencies at which nontrivial solutions of the Helmholtz Equation occur are... 

TE (transversal electric) mode Electromagnetic field distribution in which electric field vector lies in the plane perpendicular to the propagation direction. 

The Gaussian mode is a specific case of the more generalized Hermite-Gaussian (HG) modes these are also referred to as transverse electromagnetic (TEM) modes. The TEM modes carry indices / and m, namely TEM/ where / is the number of intensity minima in the direction of the electric field oscillation, and m is the number of minima in the direction of the magnetic field oscillation (basically, the formula describing the TEMqo mode distribution (Equation (3.4)) is modified by multiplication with so-called Hermite polynomials Him x,y, 2 L). 

Both acoustic modes are polar and split into transverse A u (TO) and longitudinal (LO) with different frequencies due to macroscopic electric field. All other branches show finite nonzero frequencies at F and are known as optical modes, because they correspond to unit-cell dipole moment oscillations that can interact with an electromagnetic radiation. 

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