We develop a new score-driven model for the joint dynamics of fat-tailed realized covariance matrix observations and daily returns. The score dynamics for the unobserved true covariance matrix are robust to outliers and incidental large observations in both types of data by assuming a matrix-F distribution for the realized covariance measures and a multivariate Student's t distribution for the daily returns. The filter for the unknown covariance matrix has a computationally efficient matrix formulation, which proves beneficial for estimation and simulation purposes. We formulate parameter restrictions for stationarity and positive definiteness. Our simulation study shows that the new model is able to deal with high-dimensional settings (50 or more) and captures unobserved volatility dynamics even if the model is misspecified. We provide an empirical application to daily equity returns and realized covariance matrices up to 30 dimensions. The model statistically and economically outperforms competing multivariate volatility models out-of-sample. Supplementary materials for this article are available online.

In this paper, a scanning thermal microscopy (SThM) module with a modified Wheatstone bridge is presented. It is intended to be used with a novel four-terminal thermoresistive nanoprobe, which was designed for performing thermal measurements in standard static-mode atomic force microscopes. The modified Wheatstone bridge architecture is also compared to a Wheatstone bridge and a Thomson bridge in terms of their temperature measurement sensitivities. In fixed conditions, they are found to be (7.05 ± 0.04) μV K−1 for the modified Wheatstone, while (5.43 ± 0.06) μV K−1 for the Wheatstone and (0.91 ± 0.09) μV K−1 for the Thomson bridge. The usability of the three set-ups with four-terminal nanoprobes is also discussed. The design of devices included in the module is presented and the noise level of the modified Wheatstone bridge is estimated. A proportional–integral–derivative controller for active-mode SThM is also introduced.

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In this article, a novel microfabricated thermoresistive scanning thermal microscopy probe is presented. It is a V-shaped silicon nitride cantilever with platinum lines and a sharp off-plane nanotip. The cantilever fabrication sequence incorporates standard complementary metal oxide semiconductor technology processes and therefore provides high reproducibility, while the tip is additionally processed by focused ion beam, enabling high-sensitivity and high-resolution thermal sensing. The nanoprobe is designed for scanning thermal microscopes, operating in standard atomic force microscope setup with an optical detection system. The measurement setup, which is also presented, takes advantage of the four-point design of the probe by inclusion of a Thomson bridge and a modified Wheatstone bridge measurement electronics

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