Dynamical evolution of the Brillouin precursor in Rocard-Powles-Debye model dielectrics

When an ultrawide-band electromagnetic pulse penetrates into a causally dispersive dielectric, the interrelated effects of phase dispersion and frequency dependent attenuation alter the pulse in a fundamental way that results in the appearance of so-called precursor fields. For a Debye-type dielectric, the dynamical field evolution is dominated by the Brillouin precursor as the propagation depth typically exceeds a single penetration depth at the carrier frequency of the input pulse. This is because the peak amplitude in the Brillouin precursor decays only as the square root of the inverse of the propagation distance. This nonexponential decay of the Brillouin precursor makes it ideally suited for remote sensing. Of equal importance is the frequency structure of the Brillouin precursor. Although the instantaneous oscillation frequency is zero at the peak amplitude point of the Brillouin precursor, the actual oscillation frequency of this field structure is quite different, exhibiting a complicated dependence on both the material dispersion and the input pulse characteristics. Finally, a Brillouin pulse is defined and is shown to possess near optimal (if not optimal) penetration into a given Debye-type dielectric.

[1]  K. Oughstun,et al.  Noninstantaneous, finite rise-time effects on the precursor field formation in linear dispersive pulse propagation , 1995 .

[2]  L. Brillouin,et al.  Über die Fortpflanzung des Lichtes in dispergierenden Medien , 1914 .

[3]  J. McConnell,et al.  Rotational Brownian motion and dielectric theory , 1980 .

[4]  K. Oughstun Dynamical Structure of the Precursor Fields in Linear Dispersive Pulse Propagation in Lossy Dielectrics , 1995 .

[5]  D. A. Dunnett Classical Electrodynamics , 2020, Nature.

[6]  F. Olver Why Steepest Descents , 1970 .

[7]  R. Fox,et al.  Classical Electrodynamics, 3rd ed. , 1999 .

[8]  Jakob J. Stamnes,et al.  UNIFORM ASYMPTOTIC DESCRIPTION OF THE BRILLOUIN PRECURSOR IN A SINGLE-RESONANCE LORENTZ MODEL DIELECTRIC , 1998 .

[9]  George C. Sherman,et al.  Uniform asymptotic description of electromagnetic pulse propagation in a linear dispersive medium with absorption (the Lorentz medium) , 1989 .

[10]  Shane Cloude,et al.  Ultra-Wideband, Short-Pulse Electromagnetics 5 , 2002 .

[11]  A. Sommerfeld,et al.  Über die Fortpflanzung des Lichtes in dispergierenden Medien , 1914 .

[12]  George C. Sherman,et al.  Electromagnetic Pulse Propagation in Causal Dielectrics , 1994 .

[13]  C. Chester,et al.  An extension of the method of steepest descents , 1957, Mathematical Proceedings of the Cambridge Philosophical Society.

[14]  K. Oughstun Pulse propagation in a linear, causally dispersive medium , 1990, Proc. IEEE.

[15]  K. Oughstun,et al.  Dispersive pulse propagation in a double-resonance Lorentz medium , 1989 .

[16]  Electromagnetic impulse response of triply-distilled water , 1998 .

[17]  George C. Sherman,et al.  Description of Pulse Dynamics in Lorentz Media in Terms of the Energy Velocity and Attenuation of Time-Harmonic Waves , 1981 .

[18]  Sherman,et al.  Uniform asymptotic description of ultrashort rectangular optical pulse propagation in a linear, causally dispersive medium. , 1990, Physical review. A, Atomic, molecular, and optical physics.

[19]  K. Oughstun,et al.  Failure of the group-velocity description for ultrawideband pulse propagation in a causally dispersive, absorptive dielectric , 1999 .

[20]  L. Mandel Interpretation of Instantaneous Frequencies , 1974 .

[21]  Z. Kam,et al.  Absorption and Scattering of Light by Small Particles , 1998 .

[22]  G. Sherman,et al.  Propagation of electromagnetic pulses in a linear dispersive medium with absorption (the Lorentz medium) , 1988 .

[23]  P. Debye,et al.  Näherungsformeln für die Zylinderfunktionen für große Werte des Arguments und unbeschränkt veränderliche Werte des Index , 1909 .

[24]  Oughstun,et al.  Uniform asymptotic description of ultrashort Gaussian-pulse propagation in a causal, dispersive dielectric. , 1993, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[25]  Nicholas Chako,et al.  Wave propagation and group velocity , 1960 .

[26]  E. B. Wilson,et al.  The Theory of Electrons , 1911 .

[27]  K. Oughstun,et al.  Electromagnetic energy dissipation and propagation of an ultrawideband plane wave pulse in a causally dispersive dielectric , 1998 .