[PDF]    http://dx.doi.org/10.3952/lithjphys.45305

Open access article / Atviros prieigos straipsnis

Lith. J. Phys. 45, 161–165 (2005)


PHASE AND GROUP VELOCITIES IN THE MEDIA WITH NON-DEBYE RELAXATION
P. Miškinis
Department of Physics, Faculty of Fundamental Sciences, Vilnius Gediminas Technical University, Saulėtekio 11, LT-10223 Vilnius, Lithuania
E-mail: paulius.miskinis@fm.vtu.lt

Received 24 May 2005

Dispersion and absorption in the media with stretch exponential or Kohlrausch–Williams–Watts relaxation are considered. The frequency-dependent dispersion and absorption coefficients, phase and group velocities are obtained and compared with Debye–Mandelshtam–Leontovich expressions.
Keywords: non-Debye relaxation, phase and group velocities
PACS: 51.40.+p, 62.60.+v, 62.80.+f


FAZINIS IR GRUPINIS GREIČIAI NE DEBAJAUS RELAKSACIJOS APLINKOJE
P. Miškinis
Vilniaus Gedimino technikos universitetas, Vilnius, Lietuva

Pateikiamos fazinio ir grupinio greičių išraiškos ne Debajaus relaksacijos aplinkoje. Parodyta, kad Kohlrausch, Williams ir Watts relaksacijos atveju dažninės fazinio ir grupinio greičių priklausomybės kokybiškai skiriasi nuo analogiškų priklausomybių Debajaus relaksacijos atveju. Įvertinti dispersijos ir sugerties koeficientai. Šitokiu metodu gali būti nagrinėjami dispersiniai sąryšiai ir kitose aplinkose su kitomis relaksacijos funkcijomis.


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