Tunable coupling of two mechanical resonators by a graphene membrane

Coupled nanomechanical resonators are interesting for both fundamental studies and practical applications as they offer rich and tunable oscillation dynamics. At present, the mechanical coupling in such systems is often mediated by a fixed geometry, such as a joint clamping point of the resonators or a displacement-dependent force. Here we...

Frequency stability of graphene nonlinear resonators

In pursuit of extremely sensitive sensors, the dimensions of these sensors get smaller and smaller. Small scale resonators are commonly used as sensors by relating changes in the dynamic behaviour to a sensed quantity. Conventionally, the dynamics used for sensing are in the linear regime. But at smaller scales the dynamic range of the linear...

Graphene squeeze-film microphone

Within this research a nouvelle microphone design is posed, modelled and tested. The design consists of a cavity covered by a membrane and having a venting channel, it uses the squeeze-film effect in order to link pressure to the membranes resonance and by extension acoustics to the membranes resonance. In [1] the squeeze-film effect was first...

Graphene Gas Sensor

Gas permeation through graphene membranes has received considerable<br/>attention for water purification and molecular sieving applications. However,<br/>characterization of the permeation has been limited to long timescales<br/>of minutes. This thesis shows a method for measuring gas permeation<br/>through porous graphene membranes at the...

Two-dimensional membranes in motion

This thesis revolves around nanomechanical membranes made of suspended two - dimensional materials. Chapters 1-3 give an introduction to the field of 2D-based nanomechanical devices together with an overview of the underlying physics and the measurementtools used in subsequent chapters. The research topics that are discussed can bedivided into...

Freestanding 2D Materials and their Applications: From Lab to Fab

Optothermally excited parametric resonance in monolayer graphene nanodrum resonators

Ever since its inception, graphene has been the subject of research in many parts of the<br/>world. This is due to its exceptional mechanical and electrical properties, which makes it<br/>ideal for NanoElectroMechanical (NEMS) devices. The inherent nature of NEMS devices,<br/>includes low damping, large amplitudes of oscillation, resonant...