An inverse problem framework for reconstruction of phonon properties using solutions of the Boltzmann transport equation

A methodology for reconstructing phonon properties in a solid material, such as the frequency-dependent relaxation time distribution, from thermal spectroscopy experimental results is proposed and extensively validated. The reconstruction is formulated as a non-convex optimization problem whose goal is to minimize the difference between the experimental results and the one calculated by a Boltzmann transport equation (BTE)-based model of the experimental process, with the desired material property treated as the unknown in the optimization process. Crucially, the proposed approach makes no assumption of an underlying Fourier behavior, thus avoiding all approximations associated with that assumption. The proposed method combines a derivative-free optimization method, referred to as the Nelder-Mead algorithm, with a graduated (multi-stage) optimization framework.

Name thesis:degree_name

Doctoral

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Mechanical Engineering

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2019

Author dc:creator

• Forghani, Mojtaba.

Advisor dc:contributor.advisor

• Nicolas G. Hadjiconstantinou.

• Mechanical Engineering.

Statement dc:rights

• MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

https://hdl.handle.net/1721.1/123770

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/123770