In this thesis work a study on lattice dynamics of Cerium Bismuth and phonon anomalies of Cerium Antimony by means of IXS and TDS is presented. The study of lattice dynamics allow to obtain the dispersion curves of the material, and from these it is possible to have access to a lot of physical properties such as sound velocities and elastic constants. The analysis of the phonon anomalies is performed at low temperature, 14 K, where it is possible to observe super-lattice structures made by a periodic succession of paramagnetic and ferromagnetic planes. At the end, in order to give an explanation to the experimental data, a possible alternative model is presented.
Questa tesi tratta lo studio della dinamica reticolare nel Cerio Bismuto e l'analisi delle anomalie strutturali nel Cerio Antimonio, utilizzando due tecniche sperimentali: IXS e TDS. Lo studio della dinamica reticolare porta ad acquisire le curve di dispersione del composto, dalle quali è possibile determinare diverse proprietà del materiale come velocità del suono e costanti elastiche. L'analisi delle anomalie è invece fatta a bassa temperatura, 14 K, dove si osservano delle super strutture formate da piani atomici paramagnetici e ferromagnetici in successione periodica. Data la particolarità dei dati ottenuti, viene infine presentato un possible modello alternativo per l'interpretazione di queste anomalie.
Lattice dynamics and phonon anomalies in Cerium compounds. The particular case of CeBi and CeSb
MARIANI, EDOARDO
2016/2017
Abstract
In this thesis work a study on lattice dynamics of Cerium Bismuth and phonon anomalies of Cerium Antimony by means of IXS and TDS is presented. The study of lattice dynamics allow to obtain the dispersion curves of the material, and from these it is possible to have access to a lot of physical properties such as sound velocities and elastic constants. The analysis of the phonon anomalies is performed at low temperature, 14 K, where it is possible to observe super-lattice structures made by a periodic succession of paramagnetic and ferromagnetic planes. At the end, in order to give an explanation to the experimental data, a possible alternative model is presented.File | Dimensione | Formato | |
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https://hdl.handle.net/10589/136944