A very sensitive dielectric resonator technique is employed to measure loss tangent and relative permittivity of lanthanum aluminate single crystals at 4–300 K and 4–12 GHz. A variety of single crystals grown by different techniques and purchased from different suppliers are considered. For the loss tangent is almost sample independent with linear frequency dependence and monotonous temperature variation from at 300 K to at 150 K and 4.1 GHz. In this temperature range the experimental data are explained by a model based on lifetime broadened two-phonon difference processes. The loss tangent below 150 K is characterized by a peak in at about 70 K. The height of this peak is frequency and strongly sample dependent. This leads to a variation of the loss tangent from to at 77 K and 8.6 GHz, the lowest values are generally achieved with Verneuil grown crystals and approach the intrinsic lower limit predicted by the phonon model. The peak is explained by defect dipole relaxation (local motions of ions). The activation energy of the relaxation process is determined from the measured data to be 31 meV. This low value indicates that the defect dipoles are associated with interstitials, possibly impurities in interstitial positions. Considering absorption due to phonons and due to defect dipole relaxation the loss tangent is calculated for a wide frequency range.
Skip Nav Destination
Article navigation
1 December 1997
Research Article|
December 01 1997
Microwave absorption in single crystals of lanthanum aluminate
Claudio Zuccaro;
Claudio Zuccaro
Forschungszentrum Jülich GmbH, Institut für Festkörperforschung, D-52425 Jülich, Germany
Search for other works by this author on:
Michael Winter;
Michael Winter
Forschungszentrum Jülich GmbH, Institut für Festkörperforschung, D-52425 Jülich, Germany
Search for other works by this author on:
Norbert Klein;
Norbert Klein
Forschungszentrum Jülich GmbH, Institut für Festkörperforschung, D-52425 Jülich, Germany
Search for other works by this author on:
Knut Urban
Knut Urban
Forschungszentrum Jülich GmbH, Institut für Festkörperforschung, D-52425 Jülich, Germany
Search for other works by this author on:
J. Appl. Phys. 82, 5695–5704 (1997)
Article history
Received:
June 02 1997
Accepted:
August 29 1997
Citation
Claudio Zuccaro, Michael Winter, Norbert Klein, Knut Urban; Microwave absorption in single crystals of lanthanum aluminate. J. Appl. Phys. 1 December 1997; 82 (11): 5695–5704. https://doi.org/10.1063/1.366433
Download citation file:
Sign in
Don't already have an account? Register
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Pay-Per-View Access
$40.00
Citing articles via
A step-by-step guide to perform x-ray photoelectron spectroscopy
Grzegorz Greczynski, Lars Hultman
Selecting alternative metals for advanced interconnects
Jean-Philippe Soulié, Kiroubanand Sankaran, et al.
Machine learning for thermal transport
Ruiqiang Guo, Bing-Yang Cao, et al.
Related Content
Analysis and simulation of optical and magnetic properties of lanthanide aluminates LnMgAl11O19 (Ln=La/Nd,La/Eu,Pr) with magnetoplumbite‐like structure
J. Chem. Phys. (June 1985)
Growth and Characterization of Spinel Single Crystals for Substrate Use in Integrated Electronics
J. Appl. Phys. (August 1969)
Dielectric properties of highly resistive GaN crystals grown by ammonothermal method at microwave frequencies
AIP Advances (March 2016)
Preparation, structure, optical, and magnetic properties of lanthanide aluminate single crystals (LnMAl11O19)
J. Appl. Phys. (November 1981)
Steady‐State Studies in the Conventional Verneuil Process—A Working Model for Burnout
J. Chem. Phys. (July 1966)