Category Physics

Scientists Visualize Quantum Behavior of Hot Electrons for first time

The Scanning Tunnelling Microscope used to inject electrons into a silicon surface at the University of Birmingham. Credit: Michelle Tennison

The Scanning Tunnelling Microscope used to inject electrons into a silicon surface at the University of Birmingham. Credit: Michelle Tennison

The findings present a promising step forward towards being able to manipulate and control the behavior of high energy, or ‘hot’, electrons. A Scanning Tunnelling Microscope was used to inject electrons into a silicon surface, decorated with toluene molecules. As the injected charge propagated from the tip, it induced the molecules to react and ‘lift off’ from the surface. By measuring the precise atomic positions from which molecules departed on injection, the team were able to identify that electrons were governed by quantum mechanics close to the tip, and then by more classical behavior further away.

The team found the molecular lift-off was “su...

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Quantum computing advances with Control of Entanglement

quantum

Generation of one-million-mode continuous-variable cluster state by unlimited time-domain multiplexing,” by Jun-ici Yoshikawa, Shota Yokoyama, Tishiyuki Kaji, Chanond Sornphiphatphong, Yu Shiozawa, Kenzo Makino and Akira Furusawa, APL Photonics, September 27, 2016, scitation.aip.org/content/aip/journal/app/1/6/10.1063/1.4962732.

When the quantum computer was imagined 30 years ago, it was revered for its potential to quickly and accurately complete practical tasks considered impossible for conventional computers. But, there was one big catch: Tiny-scale quantum effects fall apart too easily to be practical for reliably powering computers. Now, a team of scientists in Japan may have overcome this obstacle...

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Photons do the Twist, and scientists can now measure it

Photons do the twist, and scientists can now measure it

Measurement of the twisting force, or torque, generated by light on a silicon chip holds promise for applications such as miniaturized gyroscopes and sensors to measure magnetic field, which can have significant industrial and consumer impact. Credit: University of Minnesota

Researchers in the University of Minnesota’s College of Science and Engineering have measured the twisting force, or torque, generated by light on a silicon chip. Their work holds promise for applications such as miniaturized gyroscopes and torsional sensors to measure magnetic field, which can have significant industrial and consumer impact. Torque, in the context of light, stems from the spin angular momentum of photons (particles of light), and its measurement is mechanical proof of the quantum nature of light...

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Materials scientists prove 70-year-old tensile deformation prediction

Materials scientists prove 70-year-old tensile deformation prediction

A soft architected material that, due to the tension instability, undergoes a pattern transformation when biaxially stretched. Credit: Johannes T.B. Overvelde/Harvard SEAS

Imagine pulling or compressing a block of soft material – like rubber – equally in all directions. You wouldn’t expect the block to deform much because of the nature of the material. However, in 1948, an applied mathematician named Ronald Rivlin predicted that with the right amount of tensile force, a thick cube of soft material would suddenly deform into a thin, flat plate. For almost 70 years, this prediction remained purely theoretical. Materials scientists, hoping to add the instability to the pantheon of material functionality, were unable to prove the theory experimentally.

Recently, researchers at Harvard John A...

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