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1. Interfacial cavitation

   https://doi.org/10.1093/pnasnexus/pgac217  

   Henzel, Thomas; Nijjer, Japinder; Chockalingam, S.; Wahdat, Hares; Crosby, Alfred J.; Yan, Jing; Cohen, Tal; Grest, ed., Gary (October 2022, PNAS Nexus)

   Abstract Cavitation has long been recognized as a crucial predictor, or precursor, to the ultimate failure of various materials, ranging from ductile metals to soft and biological materials. Traditionally, cavitation in solids is defined as an unstable expansion of a void or a defect within a material. The critical applied load needed to trigger this instability -- the critical pressure -- is a lengthscale independent material property and has been predicted by numerous theoretical studies for a breadth of constitutive models. While these studies usually assume that cavitation initiates from defects in the bulk of an otherwise homogeneous medium, an alternative and potentially more ubiquitous scenario can occur if the defects are found at interfaces between two distinct media within the body. Such interfaces are becoming increasingly common in modern materials with the use of multimaterial composites and layer-by-layer additive manufacturing methods. However, a criterion to determine the threshold for interfacial failure, in analogy to the bulk cavitation limit, has yet to be reported. In this work, we fill this gap. Our theoretical model captures a lengthscale independent limit for interfacial cavitation, and is shown to agree with our observations at two distinct lengthscales, via two different experimental systems. To further understand the competition between the two cavitation modes (bulk versus interface), we expand our investigation beyond the elastic response to understand the ensuing unstable propagation of delamination at the interface. A phase diagram summarizes these results, showing regimes in which interfacial failure becomes the dominant mechanism. 

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2. Excitation of interfacial waves via surface–interfacial wave interactions

   https://doi.org/10.1017/jfm.2019.1033  

   Zaleski, Joseph; Zaleski, Philip; Lvov, Yuri V. (March 2020, Journal of Fluid Mechanics)

   We consider interactions between surface and interfacial waves in a two-layer system. Our approach is based on the Hamiltonian structure of the equations of motion, and includes the general procedure for diagonalization of the quadratic part of the Hamiltonian. Such diagonalization allows us to derive the interaction cross-section between surface and interfacial waves and to derive the coupled kinetic equations describing spectral energy transfers in this system. Our kinetic equation allows resonant and near-resonant interactions. We find that the energy transfers are dominated by the class III resonances of Alam ( J. Fluid Mech. , vol. 691, 2012, pp. 267–278). We apply our formalism to calculate the rate of growth for interfacial waves for different values of wind velocity. Using our kinetic equation, we also consider the energy transfer from wind-generated surface waves to interfacial waves for the case when the spectrum of the surface waves is given by the JONSWAP spectrum and interfacial waves are initially absent. We find that such energy transfer can occur along a time scale of hours; there is a range of wind speeds for the most effective energy transfer at approximately the wind speed corresponding to white capping of the sea. Furthermore, interfacial waves oblique to the direction of the wind are also generated. 

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3. Generalization of interfacial thermal conductance based on interfacial phonon localization

   https://doi.org/10.1016/j.mtphys.2024.101516  

   Al_Keyyam, Ibrahim; Wang, Xinwei (August 2024, Materials Today Physics)
4. Chemical sensing by interfacial voltage

   https://doi.org/10.1016/j.xcrp.2022.101119  

   Wang, Yecheng; Zhang, Shuwen; Bai, Yang; Jia, Kun; Suo, Zhigang (November 2022, Cell Reports Physical Science)

   "Developing methods for chemical sensing is of importance in broad ap­ plications, including food safety, healthcare, and ecology. The work herein describes an approach to chemical sensing by interfacial voltage. A test electrode is coated with a dielectric and a receptor. When the test electrode contacts an electrolyte, the receptor adsorbs an analyte from the electrolyte. The adsorption generates an interfacial voltage, a measurement of which reports the concentration of the an­ alyte. This design de-integrates two aspects of sensing: adsorption and detection. Consequently, the test electrode can be made of any elec­ tronic conductor. This flexibility enables sensors to be fabricated without microelectronic facilities. Several species of ions and organic molecules are detected, and a wearable chemical sensor worn on a fingertip is demonstrated. Needle-shaped electrodes are developed to test soft biological tissues. Chemical sensing by interfacial voltage holds promise for the development of ubiquitous sensing technology." 

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5. Interfacial Flow around Brownian Colloids

   https://doi.org/10.1103/PhysRevLett.126.228003  

   Molaei, Mehdi; Chisholm, Nicholas G.; Deng, Jiayi; Crocker, John C.; Stebe, Kathleen J. (June 2021, Physical Review Letters)