A graphene sheet biased with a drift electric current offers a unique opportunity to attain unidirectional, backscattering-immune, and subwavelength light propagation, as proposed by T. A. Morgado and M. G. Silveirinha [ACS Photonics 5, 4253 (2018)]. Here, we investigate in detail the impact of the intrinsic nonlocal response of graphene in the dispersion characteristics of the current-driven plasmons supported by single-layer and double-layer graphene systems. It is theoretically shown that even though the nonlocal effects weaken the spectral asymmetry of the plasmon dispersion, the studied platforms can support unidirectional backscattering-immune guided modes. Our analysis also confirms that the drift-current bias can effectively pump the graphene plasmons and enhance the propagation distance. Moreover, it is shown that the nonreciprocity and optical isolation can be boosted by pairing two drift-current-biased graphene sheets due to the enhanced radiation drag by the drifting electrons.
https://journals.aps.org/prb/abstract/10.1103/PhysRevB.102.075102
encompassing an effect of spatial dispersion, i.e., nonlocality, which, by means of inverse Fourier transformation, can be translated to the optical domain as a dependence of electric permittivity on the wavevector.One of the first studies concerning nonlocality in photonic nanostructures has revealed that wire media exhibit strong nonlocality at any frequency, leading to substantial inconsistency with the local model description [1]https://www.osapublishing.org/oe/fulltext.cfm?uri=oe-28-10-15447&id=431581
Due to the essential roles of entangled microtubule networks in complicated cellular activities such as mechanotransduction, improving the insight into their mechanical properties and dynamic load-transfer mechanisms can be inspiring to design new bio-nano-metamaterials. Damping effects arising from the polymeric nature of the microtubules as well as the surrounding cytosol in vivo and stabilizing agents in vitro can play significant roles in the dynamic behavior of the individual microtubules and their networks. Hence, this paper presents a comprehensive analysis of damping effects on elastic wave-propagation characteristics of microtubule-based metamaterials.
https://www.sciencedirect.com/science/article/abs/pii/S0020740320311085
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