Broadband characterization of congruent lithium niobate from mHz to optical frequencies. (17th August 2017)

• Record Type: Journal Article
• Authors: Cochard, Charlotte; Spielmann, Thiemo; Bahlawane, Naoufal; Halpin, Alexei; Granzow, Torsten
• Is Part Of: Journal of physics. Volume 50:Number 36(2017)
• Publication Date: 2017-08-17
• Subjects: lithium niobate -- dielectric dispersion -- birefringence; Physics -- Periodicals; 530
• DOI: 10.1088/1361-6463/aa80b8
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: Lithium niobate (LiNbO3 ) is a well known uniaxial ferroelectric material. Using impedance measurement, quasi-optical free-space characterization, THz time domain spectroscopy (THz–TDS) and ellipsometry, its dielectric permittivity/refractive index was characterized depending on the crystal orientation over a broad frequency range: 1 mHz to 1 PHz ( λ = 300 nm). Three different frequency ranges, separated by well identified resonances, are observed: low frequency 'free-piezoelectric' response, intermediate frequency 'clamped-ionic' response and high frequency 'electronic' response. These features are discussed with an emphasis on the role of the crystallographic structure and piezoelectric response.