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arXiv · 2012.08509

Maximum-likelihood parameter estimation in terahertz time-domain spectroscopy

Laleh Mohtashemi·Paul Westlund·Derek G. Sahota·Graham B. Lea·Ian Bushfield·Payam Mousavi·J. Steven Dodge
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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.

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Laleh Mohtashemi, Paul Westlund, Derek G. Sahota, Graham B. Lea, Ian Bushfield, Payam Mousavi, J. Steven Dodge. 2020-12-15. Maximum-likelihood parameter estimation in terahertz time-domain spectroscopy. https://doi.org/10.1364/oe.417724

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