Measurement of Refractive Index and Absorption Coefficient of Congruent and Stoichiometric Lithium Niobate in the Terahertz Range

Márta Unferdorben, Zsuzsanna Szaller, Ivett Hajdara, János Hebling, László Pálfalvi

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33 Citations (Scopus)


Time domain THz spectroscopy measurements were performed on a series of undoped and Mg-doped congruent lithium niobate crystals with 1.2, 6.1, and 8.4 mol% Mg concentrations and on undoped and Mg-doped stoichiometric lithium niobate crystals with 0.7, 1.5, and 4.2 mol% Mg concentrations with polarization parallel (extraordinary) and perpendicular (ordinary) to the z axis of the crystal at 300 K. The absorption coefficient and refractive index spectra were determined in the THz frequency range from 0.25 to ~2.5 THz. In the case of congruent samples for both polarizations, both the refractive index and the absorption coefficient have minimal values for compositions close to the photorefractive threshold. In the case of stoichiometric samples, similar tendencies close to the photorefractive threshold at lower Mg concentration were observed but only for extraordinary polarization, while for ordinary polarization the measured values, especially for the absorption coefficient, were only weakly dependent on the Mg content.

Original languageEnglish
Pages (from-to)1203-1209
Number of pages7
JournalJournal of Infrared, Millimeter, and Terahertz Waves
Issue number12
Publication statusPublished - Dec 1 2015



  • Absorption coefficient
  • Congruent lithium niobate
  • Refractive index
  • Stoichiometric lithium niobate
  • Terahertz frequency range
  • Time domain terahertz spectroscopy

ASJC Scopus subject areas

  • Radiation
  • Instrumentation
  • Condensed Matter Physics
  • Electrical and Electronic Engineering

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