More Like this

1. Photonic Crystal Slab Metalens

   https://doi.org/10.1109/IPC53466.2022.9975696  

   Liu, Zhonghe; Pan, Mingsen; Liu, Aaron; Kelly, George; Sampsell, Matthew; Liu, Jian; Zhou, Weidong (November 2022, IEEE)
2. Scalable Spike-and-Slab

   Biswas, Niloy; Mackey, Lester; Meng, Xiao-Li (July 2022, PMLR)

   Chaudhuri, Kamalika and (Ed.)

   Spike-and-slab priors are commonly used for Bayesian variable selection, due to their interpretability and favorable statistical properties. However, existing samplers for spike-and-slab posteriors incur prohibitive computational costs when the number of variables is large. In this article, we propose Scalable Spike-and-Slab (S^3), a scalable Gibbs sampling implementation for high-dimensional Bayesian regression with the continuous spike-and-slab prior of George & McCulloch (1993). For a dataset with n observations and p covariates, S^3 has order max{n^2 p_t, np} computational cost at iteration t where p_t never exceeds the number of covariates switching spike-and-slab states between iterations t and t-1 of the Markov chain. This improves upon the order n^2 p per-iteration cost of state-of-the-art implementations as, typically, p_t is substantially smaller than p. We apply S^3 on synthetic and real-world datasets, demonstrating orders of magnitude speed-ups over existing exact samplers and significant gains in inferential quality over approximate samplers with comparable cost. 

   more » « less
3. Lesser Antilles slab reconstruction reveals lateral slab transport under the Caribbean since 50 Ma

   https://doi.org/10.1016/j.epsl.2023.118561  

   Chen, Yi-Wei; Wu, Jonny; Goes, Saskia (February 2024, Earth and Planetary Science Letters)

   H Thybo (Ed.)

   The link between surface tectonic plates and mantle slabs is fundamental for paleo-tectonic reconstructions and for our understanding of mantle dynamics. Many seismic tomography-based studies have assumed vertical slab sinking and projected mantle features to the surface to reconstruct paleo-trench locations or explain tectonic features. Here, we used a slab-unfolding approach that does not require assumptions about sinking paths or rates to re-interpret the seismic structure of the Lesser Antilles slab underneath the Caribbean. A recent study invoked mainly vertical slab sinking and a highly folded and deformed slab to explain seismic Caribbean mantle structures. However, our results show that the upper-mantle Lesser Antilles slab structure can be better explained by limited intra-slab deformation and up to ~900 km lateral slab transport towards the northwest after subduction. Our results indicate that such lateral slab transport can occur even with probable weaknesses in the slab that originate from a subducted fossil ridge-transform system. We ascribe the lateral slab transport in the mantle to a kinematic connection with the North American plate, which has migrated northwestward since the Eocene. 

   more » « less
4. Spike-and-slab Lasso biclustering

   https://doi.org/10.1214/20-AOAS1385  

   Moran, Gemma E.; Ročková, Veronika; George, Edward I. (March 2021, The Annals of Applied Statistics)
5. Subduction Duration and Slab Dip

   https://doi.org/10.1029/2019GC008862  

   Hu, Jiashun; Gurnis, Michael (April 2020, Geochemistry, Geophysics, Geosystems)

   Abstract The dip angles of slabs are among the clearest characteristics of subduction zones, but the factors that control them remain obscure. Here, slab dip angles and subduction parameters, including subduction duration, the nature of the overriding plate, slab age, and convergence rate, are determined for 153 transects along subduction zones for the present day. We present a comprehensive tabulation of subduction duration based on isotopic ages of arc initiation and stratigraphic, structural, plate tectonic and seismic indicators of subduction initiation. We present two ages for subduction zones, a long‐term age and a reinitiation age. Using cross correlation and multivariate regression, we find that (1) subduction duration is the primary parameter controlling slab dips with slabs tending to have shallower dips at subduction zones that have been in existence longer; (2) the long‐term age of subduction duration better explains variation of shallow dip than reinitiation age; (3) overriding plate nature could influence shallow dip angle, where slabs below continents tend to have shallower dips; (4) slab age contributes to slab dip, with younger slabs having steeper shallow dips; and (5) the relations between slab dip and subduction parameters are depth dependent, where the ability of subduction duration and overriding plate nature to explain observed variation decreases with depth. The analysis emphasizes the importance of subduction history and the long‐term regional state of a subduction zone in determining slab dip and is consistent with mechanical models of subduction. 

   more » « less