In this study, we present a novel platform based on scanning microwave microscopy for manipulating and detecting tiny vibrations of nanoelectromechanical resonators using a single metallic tip. The tip is placed on the top of a grounded silicon nitride membrane, acting as a movable top gate of the coupled resonator. We demonstrate its ability to map mechanical modes and investigate mechanical damping effects in a capacitive coupling scheme, based on its spatial resolution.
View Article and Find Full Text PDFIn this paper, we report on an enhancement of mm-wave power performances with a vertically scaled AlN/GaN heterostructure. An AlGaN back barrier is introduced underneath a non-intentionally doped GaN channel layer, enabling the prevention of punch-through effects and related drain leakage current under a high electric field while using a moderate carbon concentration into the buffer. By carefully tuning the Al concentration into the back barrier layer, the optimized heterostructure offers a unique combination of electron confinement and low trapping effects up to high drain bias for a gate length as short as 100 nm.
View Article and Find Full Text PDFIn this work, we present the effects of stochastic force generated by white noise on the nonlinear dynamics of a circular silicon nitride membrane. By tuning the membrane to the Duffing nonlinear region, detected signals switching between low- and high-amplitudes have been observed. They are generated by noise-assisted random jumps between bistable states at room temperature and exhibit high sensitivity to the driving frequency.
View Article and Find Full Text PDFCoupled electromechanical resonators that can be independently driven/detected and easily integrated with external circuits are essential for exploring mechanical modes based signal processing and multifunctional integration. One of the main challenges lies in controlling energy transfers between distinct resonators experiencing nanoscale displacements. Here, we present a room temperature electromechanical system that mimics a "phonon-cavity", in analogy with optomechanics.
View Article and Find Full Text PDFSilicon nitride (SiN) mechanical resonators with high quality mechanical properties are attractive for fundamental research and applications. However, it is challenging to maintain these mechanical properties while achieving strong coupling to an electrical circuit for efficient on-chip integration. Here, we present a SiN drum resonator covered with an aluminum thin film, enabling large capacitive coupling to a suspended top-gate.
View Article and Find Full Text PDFRecently, we reported our methodology for isolating plasma membrane and lysosome from eukaryotic cell using superparamagnetic nanoparticles (SPMNPs). Here in this article, we report a step-by-step protocol for synthesis of hybrid gold nanoparticle (AuNP), surface functionalization of AuNPs on superparamagnetic nanoparticles (SPMNPs), and potential use of hybrid AuNP-SPMNP for efficient coupling of biomolecules.
View Article and Find Full Text PDFBaculovirus expression vector system (BEVS) is an established technology for recombinant protein expression in insect cells. Further, BEVS-mediated gene transduction of mammalian cells (BacMam) is emerging as a technique for high level recombinant protein expression in mammalian cells. Here, we describe generic method in using BEVS as a BacMam for rapid recombinant protein expression in mammalian cells.
View Article and Find Full Text PDFHere, we report our step-by-step protocol for superparamagnetic nanoparticle (SPMNP)-based endosome and lysosome isolation from HeLa. Briefly, we synthesized SPMNP 1.0 with iron oxide (FeO) core using thermal decomposition method.
View Article and Find Full Text PDFHere, we elaborate our detailed protocol for synthesis, functionalization, and application of superparamagnetic nanoparticle (SPMNP) for plasma membrane and lysosome isolation. We used standard thermal decomposition-based synthesis of iron oxide (FeO) core SPMNP 1.0.
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