Negative dielectric permittivity of nonmagnetic crystals in the terahertz waveband

• Опубліковано в: : Semiconductor Physics Quantum Electronics & Optoelectronics
• Дата: 2012
• Автори: Felinskyi, S.G., Korotkov, P.A., Felinskyi, G.S.
• Формат: Стаття
• Мова: Англійська
• Опубліковано: Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України 2012
• Онлайн доступ: https://nasplib.isofts.kiev.ua/handle/123456789/118282
• Назва журналу: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Цитувати: Negative dielectric permittivity of nonmagnetic crystals in the terahertz waveband / S.G. Felinskyi, P.A. Korotkov, G.S. Felinskyi // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2012. — Т. 15, № 1. — С. 83-88. — Бібліогр.: 9 назв. — англ.

Physical conditions for occurrence of the spectral bands with the negative
 dielectric permittivity in nonmagnetic crystalline media in the terahertz waveband have
 been studied in this work. It has been shown that damping the polar vibrations has a
 primary effect on formation of the negative dielectric permittivity in real crystals at
 resonance (terahertz) frequencies, and phonon attenuation imposes significant restrictions
 both on the frequency range and the minimum achievable value for all dielectric tensor
 components. Within frameworks of the single-oscillator model, the authors have
 obtained: i) the criterion for the existence of the negative dielectric permittivity, which is
 based on physical and spectroscopic parameters of the crystal, ii) analytical expressions
 for calculation of the frequency band where the dielectric permittivity takes negative
 values. Frequency regions and the minimum value of negative dielectric permittivity are
 quantitatively defined in the crystal LiTaO₃. It is proved the applicability of the obtained
 relationships in cases of relatively complex phonon vibration spectra.