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   https://doi.org/10.1103/PhysRevB.109.L121102  

   Wang, Xuepeng; Moessner, Roderich; Chowdhury, Debanjan (March 2024, Physical Review B)
2. Frictional Damping from Biomimetic Scales

   https://doi.org/10.1038/s41598-019-50944-0  

   Ali, Hessein; Ebrahimi, Hossein; Ghosh, Ranajay (December 2019, Scientific Reports)

   null (Ed.)

   Abstract Stiff scales adorn the exterior surfaces of fishes, snakes, and many reptiles. They provide protection from external piercing attacks and control over global deformation behavior to aid locomotion, slithering, and swimming across a wide range of environmental condition. In this report, we investigate the dynamic behavior of biomimetic scale substrates for further understanding the origins of the nonlinearity that involve various aspect of scales interaction, sliding kinematics, interfacial friction, and their combination. Particularly, we study the vibrational characteristics through an analytical model and numerical investigations for the case of a simply supported scale covered beam. Our results reveal for the first time that biomimetic scale beams exhibit viscous damping behavior even when only Coulomb friction is postulated for free vibrations. We anticipate and quantify the anisotropy in the damping behavior with respect to curvature. We also find that unlike static pure bending where friction increases bending stiffness, a corresponding increase in natural frequency for the dynamic case does not arise for simply supported beam. Since both scale geometry, distribution and interfacial properties can be easily tailored, our study indicates a biomimetic strategy to design exceptional synthetic materials with tailorable damping behavior. 

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3. Giant nonlinear damping in nanoscale ferromagnets

   https://doi.org/10.1126/sciadv.aav6943  

   Barsukov, I.; Lee, H. K.; Jara, A. A.; Chen, Y.-J.; Gonçalves, A. M.; Sha, C.; Katine, J. A.; Arias, R. E.; Ivanov, B. A.; Krivorotov, I. N. (October 2019, Science Advances)

   Magnetic damping is a key metric for emerging technologies based on magnetic nanoparticles, such as spin torque memory and high-resolution biomagnetic imaging. Despite its importance, understanding of magnetic dissipation in nanoscale ferromagnets remains elusive, and the damping is often treated as a phenomenological constant. Here, we report the discovery of a giant frequency-dependent nonlinear damping that strongly alters the response of a nanoscale ferromagnet to spin torque and microwave magnetic field. This damping mechanism originates from three-magnon scattering that is strongly enhanced by geometric confinement of magnons in the nanomagnet. We show that the giant nonlinear damping can invert the effect of spin torque on a nanomagnet, leading to an unexpected current-induced enhancement of damping by an antidamping torque. Our work advances the understanding of magnetic dynamics in nanoscale ferromagnets and spin torque devices. 

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4. Damping of gravitational waves by matter

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   Baym, Gordon; Patil, Subodh P.; Pethick, C. J. (October 2017, Physical Review D)
5. Plasmonic Landau damping in active environments

   https://doi.org/10.1103/PhysRevB.97.121403  

   Thakkar, Niket; Montoni, Nicholas P.; Cherqui, Charles; Masiello, David J. (March 2018, Physical Review B)