Researchers demonstrate Doppler effect and sonic boom in graphene devices

A team of researchers from universities in Loughborough, Nottingham, Manchester, Lancaster and Kansas (US) has revealed that sonic boom and Doppler-shifted sound waves can be created in a graphene transistor.

When a police car speeds past you with its siren blaring, you hear a distinct change in the frequency of the siren’s noise. This is the Doppler effect. When a jet aircraft’s speed exceeds the speed of sound (about 760 mph), the pressure it exerts upon the air produces a shock wave which can be heard as a loud supersonic boom or thunderclap. This is the Mach effect. The scientists discovered that a quantum mechanical version of these phenomena occurs in an electronic transistor made from high-purity graphene.

Researchers develop ultra-efficient 'clean' technique to control the properties of graphene

Researchers from Columbia University and collaborators from Korea's Sungkyunkwan University and Japan's National Institute for Materials Science have reported that graphene can be efficiently doped using a monolayer of tungsten oxyselenide (TOS) that is created by oxidizing a monolayer of tungsten diselenide.

The new results relied on a cleaner technique to manipulate the flow of electricity, giving graphene greater conductivity than metals such as copper and gold, and raising its potential for use in telecommunications systems and quantum computers.

Researchers develop simple method to achieve fine control over the integration of foreign atoms into graphene

Researchers from South Korea invented a simple way to achieve fine control over the integration of foreign atoms with graphene, developing composite graphene-based heterostructures that can be used to store energy at low cost and fabricate ultrathin, wearable electronics.

Adding foreign atoms to graphene boosts its properties ןצשעק

One way to specifically tailor graphene's properties is by integrating other materials into it, such as metals, insulators, and semiconductors, to form composite structures with desirable properties. For instance, researchers are adding metal oxides to graphene to create graphene monolayer/metal-oxide nanostructures (GML/MONSs) that have improved physical and chemical properties. However, depositing uniform layers of metal oxides over graphene without disturbing the characteristics of the graphene layer is extremely challenging.

Researchers experiment with LIG to create improved wearable health devices

A Penn State-led international research team (led by Professor Huanyu “Larry” Cheng at Penn State) recently published two studies that could boost research and development of future motion detection, tactile sensing and health monitoring devices.

Graphene made with lasers for wearable health devices image

There are various substances that can be converted into carbon to create graphene through laser radiation, in a process called laser-induced graphene (LIG). The resulting product can have specific properties determined by the original material. The team set out to test this process and has reached interesting conclusions.

Boron nitride assists in protecting graphene in order to achieve next-gen electronics

Researchers from AMO, Oxford Instruments, Cambridge University, RWTH Aachen University and the University of Wuppertal have demonstrated a new method to use plasma enhanced atomic layer deposition (PEALD) on graphene without introducing defects into the graphene itself.

Currently, the most advanced technique for depositing dielectrics on graphene is atomic layer deposition (ALD), which allows to precisely control the uniformity, the composition and the thickness of the film. The process typically used on graphene and other 2D materials is thermal water-based ALD, as it does not damage the graphene sheet. However, the lack of nucleation sites on graphene limits the quality of the dielectric film, and requires the deposition of a seed layer prior to ALD to achieve good results. Another approach is plasma enhanced atomic layer deposition (PEALD), which, when applied to growth on graphene, can introduce surface damage. This is what to team addressed in this recent work.