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Updated: 2 weeks 4 days ago

Nobel physics prize honors inventors of blue LEDs

7 October 2014

Royal Swedish Academy of Sciences: Isamu Akasaki (Meijo University, Nagoya, Japan), Hiroshi Amano (Nagoya University, Japan), and Shuji Nakamura (University of California, Santa Barbara) are the awardees of this year's Nobel Prize in Physics. From the 1970s through the 1990s, the laureates overcame a range of challenges in physics and materials science to develop efficient blue light-emitting diodes. Red and green LEDs had been available since the late 1960s. The invention of blue LEDs, which made their debut in 1993, completed the visual spectrum and made it possible for LEDs to be used for a wide variety of lighting applications. Compared with incandescent light bulbs, LEDs are 10 times more energy efficient, last 50 times longer, and are more physically robust. Given that 20–30% of the world's electricity is consumed by lighting, the widespread adoption of LED lighting should lead, in the words of the Nobel committee, "to significant energy savings of great benefit to mankind."

Nobel physics prize honors inventors of blue LEDs

7 October 2014

Royal Swedish Academy of Sciences: Isamu Akasaki (Meijo University, Nagoya, Japan), Hiroshi Amano (Nagoya University, Japan), and Shuji Nakamura (University of California, Santa Barbara) are the awardees of this year's Nobel Prize in Physics. From the 1970s through the 1990s, the laureates overcame a range of challenges in physics and materials science to develop efficient blue light-emitting diodes. Red and green LEDs had been available since the late 1960s. The invention of blue LEDs, which made their debut in 1993, completed the visual spectrum and made it possible for LEDs to be used for a wide variety of lighting applications. Compared with incandescent light bulbs, LEDs are 10 times more energy efficient, last 50 times longer, and are more physically robust. Given that 20–30% of the world's electricity is consumed by lighting, the widespread adoption of LED lighting should lead, in the words of the Nobel committee, "to significant energy savings of great benefit to mankind."

Developers of blue LEDs win 2014 physics Nobel

7 October 2014
The invention greatly extended the range of applications for efficient and long-lived solid-state lighting.

Developers of blue LEDs win 2014 physics Nobel

7 October 2014
The invention greatly extended the range of applications for efficient and long-lived solid-state lighting.

IPF 2014: Detecting stealth crop diseases

6 October 2014
Physicists help Brazilian orange groves to thrive.

IPF 2014: Detecting stealth crop diseases

6 October 2014
Physicists help Brazilian orange groves to thrive.

Peter J. Price

6 October 2014

Peter J. Price

6 October 2014

IPF 2014: Industrial physics goes global

6 October 2014
The latest Industrial Physics Forum, held this week in Campinas, Brazil, explores technological innovation in emerging economies.

IPF 2014: Industrial physics goes global

6 October 2014
The latest Industrial Physics Forum, held this week in Campinas, Brazil, explores technological innovation in emerging economies.

Richard Lewis Arnowitt

6 October 2014

Richard Lewis Arnowitt

6 October 2014

Can battery technology advance rapidly to “transform the prosperity of the world”?

6 October 2014
A Wall Street Journal column and an Atlantic magazine report present starkly contrasting outlooks.

Can battery technology advance rapidly to “transform the prosperity of the world”?

6 October 2014
A Wall Street Journal column and an Atlantic magazine report present starkly contrasting outlooks.

Bio-inspired adhesive works underwater

6 October 2014

Ars Technica: Adhesives that form bonds while immersed in water would have many uses, especially in biomedical applications. To come up with such a substance, researchers have been studying sea-dwelling organisms, such as mussels and algae, whose secretions have naturally adhesive properties. Two different types of adhesive substances were found: One uses a chemical that links proteins together and is thus considered “sticky,” and the other uses an amyloid protein assembly that forms dense fibers. When combined, the sticky proteins enhanced the diameter of the fibers, which increased the surface contact area and improved adhesion. In addition, how the material interacts with different surfaces, such as silica, gold, and polystyrene, appears to depend on the interaction between the fibrous and sticky parts.

Bio-inspired adhesive works underwater

6 October 2014

Ars Technica: Adhesives that form bonds while immersed in water would have many uses, especially in biomedical applications. To come up with such a substance, researchers have been studying sea-dwelling organisms, such as mussels and algae, whose secretions have naturally adhesive properties. Two different types of adhesive substances were found: One uses a chemical that links proteins together and is thus considered “sticky,” and the other uses an amyloid protein assembly that forms dense fibers. When combined, the sticky proteins enhanced the diameter of the fibers, which increased the surface contact area and improved adhesion. In addition, how the material interacts with different surfaces, such as silica, gold, and polystyrene, appears to depend on the interaction between the fibrous and sticky parts.

Two studies focus on ocean waters as heat sink

6 October 2014

Science: Although Earth’s oceans are as important to global climate as the atmosphere, they have not been as well studied. Two areas of particular concern are the waters of the Southern Hemisphere and those of the deep ocean, below 2000 m. Paul Durack of Lawrence Livermore National Laboratory and colleagues used satellite measurements of sea-level height to estimate ocean temperature—as water warms, it expands. According to their model simulations, estimates of the heat stored in the upper 700 m of the ocean since 1970 have been too low, due largely to the poor sampling data from the Southern Hemisphere. Another group of researchers, led by William Llovel of the Jet Propulsion Laboratory, looked at warming in the deep ocean since 2005. Because most temperature data come from buoys, more is known about water temperature in the top 2000 m, and much less is known about the temperature of the rest of the ocean, which can descend as deep as 6000 m. Comparing the available data with global sea-level rise since 2005, the researchers estimate that the deep ocean has barely warmed over the past decade. Both studies point up the need for more data, which may soon be provided by a new fleet of research buoys, dubbed Deep Argo.

Two studies focus on ocean waters as heat sink

6 October 2014

Science: Although Earth’s oceans are as important to global climate as the atmosphere, they have not been as well studied. Two areas of particular concern are the waters of the Southern Hemisphere and those of the deep ocean, below 2000 m. Paul Durack of Lawrence Livermore National Laboratory and colleagues used satellite measurements of sea-level height to estimate ocean temperature—as water warms, it expands. According to their model simulations, estimates of the heat stored in the upper 700 m of the ocean since 1970 have been too low, due largely to the poor sampling data from the Southern Hemisphere. Another group of researchers, led by William Llovel of the Jet Propulsion Laboratory, looked at warming in the deep ocean since 2005. Because most temperature data come from buoys, more is known about water temperature in the top 2000 m, and much less is known about the temperature of the rest of the ocean, which can descend as deep as 6000 m. Comparing the available data with global sea-level rise since 2005, the researchers estimate that the deep ocean has barely warmed over the past decade. Both studies point up the need for more data, which may soon be provided by a new fleet of research buoys, dubbed Deep Argo.

Measuring atmospheric carbon dioxide from space

6 October 2014
If we can account for the confounding effects of aerosols, satellite-based measurements of CO2 will improve our understanding of Earth’s carbon cycle.

Emergent effect creates quasi-Majorana particles

6 October 2014

Nature: Particles that are their own antiparticles were predicted by Ettore Majorana in 1937. None have been found in particle-physics experiments so far, but hints of Majorana-like quasiparticles have been seen in a condensed-matter system of strongly interacting electrons. Further, stronger evidence of the quasiparticles comes from a new experiment performed by Ali Yazdani of Princeton University and his colleagues. To create the quasiparticle, they placed a chain of iron atoms on top of a superconductor in such a way that the electrons in the iron atoms paired off. Each pair coordinated spins so that one of the electrons acted like a positron (the antielectron particle). The arrangement left unpaired electrons at both ends of the chain, which forced those two electrons to individually behave as both an electron and a positron. The finding strengthens the idea that true Majorana particles could exist outside of superconductors.

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