# 2019 CAP Congress / Congrès de l'ACP 2019

2-7 June 2019
Simon Fraser University
America/Vancouver timezone
Welcome to the 2019 CAP Congress Program website! / Bienvenue au siteweb du programme du Congrès de l'ACP 2019 !

## Elastic Properties of Natural Biotite Crystals by Brillouin Spectroscopy

Jun 3, 2019, 1:45 PM
15m
SCP 8445.2 (Simon Fraser University)

### SCP 8445.2

#### Simon Fraser University

Oral Competition (Graduate Student) / Compétition orale (Étudiant(e) du 2e ou 3e cycle) Condensed Matter and Materials Physics / Physique de la matière condensée et matériaux (DCMMP-DPMCM)

### Speaker

Mr Dillon Hanlon (Department of Physics and Physical Oceanography, Memorial University of Newfoundland)

### Description

Experiments were performed on natural crystals of biotite in an attempt to quantify the effects of impurities on acoustic phonon behaviour and elastic properties in this mica series. Electron probe microanalyzer(EPMA) was used to quantify the chemical compositions of biotite with differing concentrations of Fe and Mg. Brillouin light scattering spectra of these samples contained peaks due to pure transverse, quasi-transverse and quasi-longitudinal acoustic phonon modes. Analysis of these spectra permitted determination directional dependence of the velocities of these modes in the ac and bc crystallographic planes as well as the elastic constants $C_{11}$, $C_{22}$, $C_{33}$, $C_{44}$, $C_{55}$, $C_{66}$, $C_{13}$, $C_{15}$, $C_{23}$, $C_{25}$, $C_{35}$, and $C_{46}$. In general, the acoustic mode velocities decrease with increasing Fe concentration. The values of some elastic constants also appear to show a dependence on impurity and concentration.

### Primary authors

Mr Dillon Hanlon (Department of Physics and Physical Oceanography, Memorial University of Newfoundland) Dr Todd Andrews (Department of Physics and Physical Oceanography, Memorial University of Newfoundland)

### Co-author

Dr Roger Mason (Department of Earth Sciences, Memorial University of Newfoundland)