arXiv subjects

Timothy Holt

Publications and source records attributed to Timothy Holt.

4 recordsLinked to original sources

arXiv2026

Microwave Studies of Single Crystal TeO2 at Cryogenic Temperatures

We use whispering-gallery-mode analysis to characterise the microwave dielectric properties of single-crystal TeO$_2$ at cryogenic temperatures and compare its loss performance with other low-loss dielectric materials. Finite-element modelling is combined with measurements at room temperature, 4 K, and 20 mK to develop accurate cryogenic simulations and extract the anisotropic dielectric permittivities, giving $\varepsilon_\parallel=25.75\pm0.08$ and $\varepsilon_\perp=20.90\pm0.07$. Loss measurements reveal quality factors as high as $9\times10^6$ and minimum loss tangents approaching $3\times10^{-8}$, placing TeO$_2$ among promising low-loss dielectrics for cryogenic microwave applications. Electron-spin-resonance spectroscopy further indicates a clean spin environment, while identifying distinct spin systems consistent with the known properties of the crystal.

cond-mat.mtrl-sci↗

arXiv2026

Probing Light-Matter Interaction with Topological Data Analysis

We explore application of Topological Data Analysis to study light matter interaction through scattering response data in different dimensions. This method is robust against Fano resonance backgrounds in both strong and weak coupling regimes, maintaining accuracy even with reduced mode contrast, distorted lineshape, and the introduction of random trace noise. It scales to any number of interacting modes, reflecting the system's effective degrees of freedom. Crucially, TDA is not merely peak counting but reveals phase-encoded features in the scattering response and may be used even for a fully saturated amplitude response. The analysis is also applied to a three mode system with time reversal symmetry breaking, revealing change in apparent number of loops and voids in combined two way scattering data. This approach is demonstrated to differentiate the three Dyson ensembles through their topological complexity and probability density functions, enabling analysis of complex modal systems.

physics.app-ph↗

arXiv2021

Detecting Edgeworth Cycles

We develop and test algorithms to detect "Edgeworth cycles," which are asymmetric price movements that have caused antitrust concerns in many countries. We formalize four existing methods and propose six new methods based on spectral analysis and machine learning. We evaluate their accuracy in station-level gasoline-price data from Western Australia, New South Wales, and Germany. Most methods achieve high accuracy in the first two, but only a few can detect the nuanced cycles in the third. Results suggest whether researchers find a positive or negative statistical relationship between cycles and markups, and hence their implications for competition policy, crucially depends on the choice of methods. We conclude with a set of practical recommendations.

physics.soc-ph↗

arXiv2020

Enabling Effective Exoplanet / Planetary Collaborative Science

The field of exoplanetary science has emerged over the past two decades, rising up alongside traditional solar system planetary science. Both fields focus on understanding the processes which form and sculpt planets through time, yet there has been less scientific exchange between the two communities than is ideal. This white paper explores some of the institutional and cultural barriers which impede cross-discipline collaborations and suggests solutions that would foster greater collaboration. Some solutions require structural or policy changes within NASA itself, while others are directed towards other institutions, including academic publishers, that can also facilitate greater interdisciplinarity.

astro-ph.IM↗