Scientists shave ‘hairs’ off nanocrystals to improve their electronic properties

University of Chicago graduate student Josh Portner collects x-ray scattering data from tiny “supercrystals.” Scientists hope such supernanocrystals could form the basis of new technologies thanks to a new method to help them talk to one another electronically.
Credit: Talapin lab/University of Chicago

Chemists could yield future devices such as next-gen displays and solar cells. A new study introduces a breakthrough in making nanocrystals function together electronically. The research may open the doors to future devices with new abilities.

You can carry an entire computer in your pocket today because the technological building blocks have been getting smaller and smaller since the 1950s...

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Quantum Physics sets a Speed Limit to Electronics

An ultra short laser pulse (blue) creates free charge carriers, another pulse (red) accelerates them in opposite directions.

Semiconductor electronics is getting faster and faster — but at some point, physics no longer permits any increase. The speed can definitely not be increased beyond one petahertz (one million gigahertz), even if the material is excited in an optimal way with laser pulses.

How fast can electronics be? When computer chips work with ever shorter signals and time intervals, at some point they come up against physical limits. The quantum-mechanical processes that enable the generation of electric current in a semiconductor material take a certain amount of time. This puts a limit to the speed of signal generation and signal transmission.

TU Wien (Vienna), TU Gra...

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Scientists Solve Solar Secret

This conceptual image shows the Parker Solar Probe about to enter the solar corona. Credit NASA / John Hopkins APL / Ben Smith.

The further we move away from a heat source, the cooler the air gets. Bizarrely, the same can’t be said for the Sun, but University of Otago scientists may have just explained a key part of why.

Study lead Dr Jonathan Squire, of the Department of Physics, says the surface of the Sun starts at 6000 degree C, but over a short distance of only a few hundred kilometers, it suddenly heats up to more than a million degrees, becoming its atmosphere, or corona.

“This is so hot that the gas escapes the Sun’s gravity as ‘solar wind’, and flies into space, smashing into Earth and other planets.

“We know from measurements and theory that the sudden temperature ju...

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Physicists Create Extremely Compressible ‘Gas of Light’ – Paving the way to new types of highly sensitive sensors

The centerpiece of the experiment: – the optical microresonator realizes the ‘photon box’.
Photo: Volker Lannert/University of Bonn

Researchers at the University of Bonn have created a gas of light particles that can be extremely compressed. Their results confirm the predictions of central theories of quantum physics. The findings could also point the way to new types of sensors that can measure minute forces. The study is published in the journal Science.

If you plug the outlet of an air pump with your finger, you can still push its piston down. The reason: Gases are fairly easy to compress — unlike liquids, for example. If the pump contained water instead of air, it would be essentially impossible to move the piston, even with the greatest effort.

Gases usually consist of at...

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