A team of scientists led by Dr Jason Petta of Princeton University has built a rice grain-sized microwave laser, or maser, powered by single electrons tunneling through quantum dots – bits of semiconductor material that act like single atoms.
This micromaser is a major step toward building quantum-computing systems out of semiconductor materials; a battery forces electrons to tunnel one by one through two double quantum dots located at each end of a cavity, moving from a higher energy level to a lower energy level and in the process giving off microwaves that build into a coherent beam of light. Image credit: Jason Petta.
“It is basically as small as you can go with these single-electron devices,” Dr Petta said.
The device, described in the journal Science , uses about one-billionth the electric curren… Read more
A team of researchers at the University of Bristol, UK, has created a device that enables its users to touch and feel three-dimensional holograms in thin air.
Ultrasound is focused to create the shape of a virtual sphere. Image credit: © Bristol Interaction and Graphics group, University of Bristol.
“Touchable holograms, immersive virtual reality that you can feel and complex touchable controls in free space, are all possible ways of using this system,” said Dr Ben Long, the first author of the paper published in the journal ACM Transactions on Graphics .
The method developed by Dr Long and his colleagues uses ultrasound, which is focused onto hands above the device and that can be felt. By focusing complex patterns of ultrasound, the air disturbances can be seen as floating three-dimensional shapes. Read more
A team of scientists from Spain, Germany and France has managed to synthesize graphene’s cousin – an atom-thin, ordered, two-dimensional material named germanene.
STM image reveals honeycomb structure of germanene. Image credit: M E Dávila et al.
Germanene does not exist in nature and is made up of a single layer of germanium atoms. It is expected to exhibit impressive electrical and optical properties and could be widely integrated across the electronics industry in the future.
First proposed in 2009, the material has, up until now, remained elusive. Since then, graphene has been developed further whilst other two-dimensional materials, such as graphene’s silicon cousin – silicene, have been synthesized.
Much like silicene, the proposed method for synthesizing germanene is to deposit indiv… Read more
A team of scientists from Finland and the United Kingdom has engineered the common gut bacteria, Escherichia coli , to generate renewable propane.
This false-color scanning electron micrograph shows Escherichia coli . Image credit: Rocky Mountain Laboratories / NIAID / NIH.
Propane is a naturally occurring gas composed of three carbon atoms and eight hydrogen atoms. It is produced as a by-product of two processes – natural gas processing and petroleum refining – but both are finite resources.
In its current form it makes up the bulk of liquid petroleum gas, which is used in many applications, from central heating to camping stoves and conventional motor vehicles.
In a research paper released by the journal Nature Communications , Dr Patrik Jones of Imperial College London and the University of Turk… Read more
The newly developed transparent luminescent solar concentrator can be used on buildings, cell phones and any other device that has a clear surface, says a group of scientists led by Dr Richard Lunt of Michigan State University.
This image shows a transparent luminescent solar concentrator module. Image credit: Yimu Zhao.
Research in the production of energy from solar cells placed around luminescent materials is not new.
Past efforts, however, have yielded poor results – the energy production was inefficient and the materials were highly colored.
Now Dr Lunt and his colleagues at Michigan State University have developed transparent luminescent materials that use small organic molecules to absorb specific non-visible wavelengths of sunlight.
“We can tune these materials to pick up just the UV… Read more