Category Physics

Research reveals Exotic Quantum States in Double-layer Graphene

A new type of quasiparticle is discovered in graphene double-layer structure. This so-called composite fermion consists of one electron and two different types of magnetic flux, illustrated as blue and gold colored arrows in the figure. Composite fermions are capable of forming pairs, such unique interaction leads to experimental discovery of unexpected new quantum Hall phenomena.

Researchers from Brown and Columbia Universities have demonstrated previously unknown states of matter that arise in double-layer stacks of graphene, a 2D nanomaterial. These new states, known as the fractional quantum Hall effect, arise from the complex interactions of electrons both within and across graphene layers.

“The findings show that stacking 2D materials together in close proximity generates en...

Read More

A New ‘Golden’ Age for Electronics?

Samarium sulfide doped with various rare earth elements shrinks as the temperature increases from about minus 175°C to about 40-60°C. Shown here is the relative linear shrinkage compared to the length at about 120°C. For the Cerium (Ce) dopant, the percentage volume decrease is about 2.6%. These samples were produced by an industrially scalable process, paving the way for practical applications of this class of sulfides as thermal-expansion compensators.
CREDIT
K. Takenaka/John Wojdylo

Materials that shrink when heated – changing color from black to golden – could save expensive electronics from heat damage.
Scientists have created materials that shrink uniformly in all directions when heated under normal everyday conditions, using a cheap and industrially scalable process...

Read More

Researchers create Multi-junction Solar Cells from Off-the-shelf Components

Multi-junction solar cell with indium
“A New Approach for Multi-Junction Solar Cells from Off-the-Shelf Individual Cells: GaAs/Si”
Authors: Brandon Hagar, Peter Colter, Salah Bedair, North Carolina State University
Presented: June 19, IEEE Photostatic Specialist Meeting, Chicago

Multi-junction solar cells are both the most efficient type of solar cell on the market today and the most expensive type of solar cell to produce. In a proof-of-concept paper, researchers from North Carolina State University detail a new approach for creating multi-junction solar cells using off-the-shelf components, resulting in lower cost, high-efficiency solar cells for use in multiple applications.

Multi-junction, or stacked, solar cells are currently the most efficient cells on the market, converting up to 45% of the solar energy they a...

Read More

First-ever Successful Mind-Controlled Robotic Arm without Brain Implants

 Breakthrough in Non-Invasive Mind-Control of Robotic Limbs

A team of researchers from Carnegie Mellon University, in collaboration with the University of Minnesota, has made a breakthrough in the field of noninvasive robotic device control. Using a noninvasive brain-computer interface (BCI), researchers have developed the first-ever successful mind-controlled robotic arm exhibiting the ability to continuously track and follow a computer cursor.

Being able to noninvasively control robotic devices using only thoughts will have broad applications, in particular benefiting the lives of paralyzed patients and those with movement disorders.

BCIs have been shown to achieve good performance for controlling robotic devices using only the signals sensed from brain implants...

Read More