Maximum-Likelihood Parameter Estimation in Terahertz Time-Domain Spectroscopy

Peer reviewed: 
Yes, item is peer reviewed.
Scholarly level: 
Faculty/Staff
Final version published as: 

Mohtashemi, L., Westlund, P., Sahota, D. G., Lea, G. B., Bushfield, I., Mousavi, P., & Dodge, J. S. (2021). Maximum-likelihood parameter estimation in terahertz time-domain spectroscopy. Opt. Express, 29(4), 4912–4926. https://doi.org/10.1364/OE.417724.

Date created: 
2021-02-15
Identifier: 
DOI: 10.1364/OE.417724
Keywords: 
Terahertz Time-Domain Spectroscopy
Abstract: 

We present a maximum-likelihood method for parameter estimation in terahertz time-domain spectroscopy. We derive the likelihood function for a parameterized frequency response function, given a pair of time-domain waveforms with known time-dependent noise amplitudes. The method provides parameter estimates that are superior to other commonly used methods and provides a reliable measure of the goodness of fit. We also develop a simple noise model that is parameterized by three dominant sources and derive the likelihood function for their amplitudes in terms of a set of repeated waveform measurements. We demonstrate the method with applications to material characterization.

Language: 
English
Document type: 
Article
File(s): 
Sponsor(s): 
Natural Sciences and Engineering Research Council of Canada (NSERC)
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