Tymofiy Khodkov | Searcharxiv

arXiv2021

Engineering tunable strain fields in suspended graphene by microelectromechanical systems

Here, we present a micro-electromechanical system (MEMS) for the investigation of the electromechanical coupling in graphene and potentially related 2D materials. Key innovations of our technique include: (1) the integration of graphene into silicon-MEMS technology; (2) full control over induced strain fields and doping levels within the graphene membrane and their characterization via spatially resolved confocal Raman spectroscopy; and (3) the ability to detect the mechanical coupling of the graphene sheet to the MEMS device with via their mechanical resonator eigenfrequencies.

cond-mat.mes-hall↗

arXiv2020

Far-field Excitation of Single Graphene Plasmon Cavities with Ultra-compressed Mode-volumes

Acoustic-graphene-plasmons (AGPs) are highly confined electromagnetic modes, carrying large momentum and low loss in the mid-infrared/Terahertz spectra. Owing to their ability to confine light to extremely small dimensions, they bear great potential for ultra-strong light-matter interactions in this long wavelength regime, where molecular fingerprints reside. However, until now AGPs have been restricted to micron-scale areas, reducing their confinement potential by several orders-of-magnitude. Here, by utilizing a new type of graphene-based magnetic-resonance, we realize single, nanometric-scale AGP cavities, reaching record-breaking mode-volume confinement factors of $\thicksim5\cdot10^{-10}$. This AGP cavity acts as a mid-infrared nanoantenna, which is efficiently excited from the far-field, and electrically tuneble over an ultra-broadband spectrum. Our approach provides a new platform for studying ultra-strong-coupling phenomena, such as chemical manipulation via vibrational-strong-coupling, and a path to efficient detectors and sensors, in this challenging spectral range.

physics.optics↗