PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Ultrafast remote switching of light emission

Ultrafast remote switching of light emission
2014-09-30
(Press-News.org) This news release is available in German.

The researchers etched a photonic crystal around several quantum dots in a semiconductor layer. Quantum dots are small structures that spontaneously emit light as a consequence of atomic processes. If a short laser pulse is fired at the photonic crystal, its refractive index is modified and the quantum dot experiences a change in the electromagnetic field around it. This change can speed up or slow down the emission of light by the dot. As soon as the refractive index recovers its usual value, the dot emits light again in the normal manner.

Ultrashort light flash Using this technique the spontaneous emission of light by the dot can be switched on and off at will. The most striking feature of this method is that the duration of the light flash can be made considerably shorter than the natural lifetime of such a dot as a light source. In the current article the researchers describe an experiment in which the light pulse was 200 picoseconds (trillionths of a second) long. Based on the underlying theory, the researchers expect to be able to make these light pulses another factor of ten shorter. Furthermore, the researchers demonstrated that the emission of the light source could be controlled using a laser pulse at a relatively large distance from the source.

Quantum information This result is important for the transmission of quantum information, for example. This requires light sources that can emit individual photons (light particles). Being able to control time-dependent properties of these photons is important for the exchange of quantum information between different parties. The method now proposed for the remote control of the light source makes this possible without influencing the other properties of the emitted photons.

INFORMATION: The researchers used the NanoLab@TU/e facilities to make the special structure that holds a quantum dot in a photonic crystal. The research was funded by NanoNextNL, STW and FOM.

Reference Ultrafast nonlocal control of spontaneous emission, Chao-Yuan Jin, Robert Johne, Milo Y. Swinkels, Thang B. Hoang, Leonardo Midolo, Peter J. van Veldhoven, and Andrea Fiore. The article is available at Nature Nanotechnology http://dx.doi.org/10.1038/nnano.2014.190

Further information Prof. Andrea Fiore, +31 (40) 247 21 18 Dr Chao-Yuan Jin, +31 (6) 302 39 122

[Attachments] See images for this press release:
Ultrafast remote switching of light emission

ELSE PRESS RELEASES FROM THIS DATE:

'Virtual breast' could improve cancer detection

Virtual breast could improve cancer detection
2014-09-30
Next to lung cancer, breast cancer is the leading cause of cancer death in women, according to the American Cancer Society. That's why so many medical professionals encourage women to get mammograms, even though the tests are imperfect at best: only a minority of suspicious mammograms actually leads to a cancer diagnosis. That results in lots of needless worry for women and their families—not to mention the time, discomfort and expense of additional tests, including ultrasounds and biopsies. Recently, a different type of test, ultrasound elastography, has been used ...

Rehospitalization in younger patients

2014-09-30
Older adults often are readmitted after hospitalization for heart failure, pneumonia, and acute myocardial infarction, a significant issue that has caused Medicare to target hospitals with high 30-day readmission rates for financial penalties. Older adults are also often admitted for reasons other than the original hospitalization. This vulnerability to readmission has been referred to as "post-hospital syndrome." However, whether younger patients also experience a similar pattern of readmission has not been well studied. In a large cohort study, Isuru Ranasinghe and ...

Diuretics in proton pump inhibitor-associated hypomagnesemia

2014-09-30
Proton pump inhibitor (PPI) therapy is associated with hospitalization for hypomagnesemia, particularly among patients also receiving diuretics, according to research published this week in PLOS Medicine. The study, conducted by David Juurlink of the University of Toronto and colleagues, suggests that physicians reconsider long-term PPI therapy for patients with a diagnosis of hypomagnesemia or concurrent use of diuretics. Roughly 145 million prescriptions for PPI are dispensed in the United States annually for acid-related disorders such as dyspepsia and gastroesophageal ...

At dusk and dawn: Scientists pinpoint biological clock's synchronicity

2014-09-30
Scientists have uncovered how pacemaker neurons are synchronized at dusk and dawn in order to maintain the proper functioning of their biological clocks. Their findings, which appear in the journal PLOS Biology, enhance our understanding of how sleep-wake cycles are regulated and offer promise for addressing related afflictions. "We've known for some time that the time-keeping of our biological clocks is a complex enterprise," says New York University's Justin Blau, a professor of biology and neural science and one of the study's co-authors. "But our results offer new ...

How dinosaur arms turned into bird wings

2014-09-30
Although we now appreciate that birds evolved from a branch of the dinosaur family tree, a crucial adaptation for flight has continued to puzzle evolutionary biologists. During the millions of years that elapsed, wrists went from straight to bent and hyperflexible, allowing birds to fold their wings neatly against their bodies when not flying. How this happened has been the subject of much debate, with substantial disagreement between developmental biologists, who study how the wings of modern birds develop in the growing embryo, and palaeontologists who study the bones ...

Study shows how chimpanzees share skills

Study shows how chimpanzees share skills
2014-09-30
Evidence of new behaviour being adopted and transmitted socially from one individual to another within a wild chimpanzee community is publishing on September 30 in the open access journal PLOS Biology. This is the first instance of social learning recorded in the wild. Scientists from University of St Andrews, University of Neuchâtel, Anglia Ruskin University, and Université du Quebec studied the spread of two novel tool-use behaviours among the Sonso chimpanzee community living in Uganda's Budongo Forest. Dr Catherine Hobaiter, Lecturer in Psychology at the University ...

Boys and girls who've had a traumatic brain injury differ in rates of harmful behavior

2014-09-30
TORONTO, Sept. 30, 2014 – Teenagers who said they had a traumatic brain injury in their lifetime, especially girls, also reported significantly higher rates of harmful behavior, according to new research. The study looked at 13 harmful health behaviours –such as contemplating suicide, smoking marijuana or binge drinking– among 9,288 Ontario students between Grades 7 and 12. "Both boys and girls were more likely to engage in a variety of harmful behaviours if they reported a history of TBI, but girls engaged in all 13 harmful behaviours we looked for, whereas boys were ...

Blades of grass inspire advance in organic solar cells

Blades of grass inspire advance in organic solar cells
2014-09-30
AMHERST, Mass. – Using a bio-mimicking analog of one of nature's most efficient light-harvesting structures, blades of grass, an international research team led by Alejandro Briseno of the University of Massachusetts Amherst has taken a major step in developing long-sought polymer architecture to boost power-conversion efficiency of light to electricity for use in electronic devices. Briseno, with colleagues and graduate students at UMass Amherst and others at Stanford University and Dresden University of Technology, Germany, report in the current issue of Nano Letters ...

Comprehensive Study of allergic deaths in US finds medications are main culprit

2014-09-30
September 30, 2014—(BRONX, NY)—Medications are the leading cause of allergy-related sudden deaths in the U.S., according to an analysis of death certificates from 1999 to 2010, conducted by researchers at Montefiore Medical Center and Albert Einstein College of Medicine of Yeshiva University. The study, published online today in the Journal of Allergy and Clinical Immunology, also found that the risk of fatal drug-induced allergic reactions was particularly high among older people and African-Americans and that such deaths increased significantly in the U.S. in recent ...

The cultural side of science communication

2014-09-30
EVANSTON, Ill. --- Do we think of nature as something that we enjoy when we visit a national park and something we need to "preserve?" Or do we think of ourselves as a part of nature? A bird's nest is a part of nature, but what about a house? The answers to these questions reflect different cultural orientations. They are also reflected in our actions, our speech and in cultural artifacts. A new Northwestern University study, in partnership with the University of Washington, the American Indian Center of Chicago and the Menominee tribe of Wisconsin, focuses on science ...

LAST 30 PRESS RELEASES:

Modesty and boastfulness – perception depends on usual performance

Do sweeteners increase your appetite? New evidence from randomised controlled trial says no 

Women with obesity do not need to gain weight during pregnancy, new study suggests

Individuals with multiple sclerosis face substantially greater risk of hospitalisation and death from COVID-19, despite high rates of vaccination

Study shows obesity in childhood associated with a more than doubling of risk of developing multiple sclerosis in early adulthood

Rice Emerging Scholars Program receives $2.5M NSF grant to boost STEM education

Virtual rehabilitation provides benefits for stroke recovery

Generative AI develops potential new drugs for antibiotic-resistant bacteria

Biofuels could help island nations survive a global catastrophe, study suggests

NJIT research team discovering how fluids behave in nanopores with NSF grant

New study shows association of historical housing discrimination and shortfalls in colon cancer treatment

Social media use may help to empower plastic surgery patients

Q&A: How to train AI when you don't have enough data

Wayne State University researchers uncover potential treatment targets for Zika virus-related eye abnormalities

Discovering Van Gogh in the wild: scientists unveil a new gecko species

Small birds spice up the already diverse diet of spotted hyenas in Namibia

Imaging detects transient “hypoxic pockets” in the mouse brain

Dissolved organic matter could be used to track and improve the health of freshwaters

Indoor air quality standards in public buildings would boost health and economy, say international experts

Positive associations between premenstrual disorders and perinatal depression

New imaging method illuminates oxygen's journey in the brain

Researchers discover key gene for toxic alkaloid in barley

New approach to monitoring freshwater quality can identify sources of pollution, and predict their effects

Bidirectional link between premenstrual disorders and perinatal depression

Cell division quality control ‘stopwatch’ uncovered

Vaccine protects cattle from bovine tuberculosis, may eliminate disease

Andrew Siemion to receive the SETI Institute’s 2024 Drake Award

New study shows how the Crimean-Congo hemorrhagic fever virus enters our cells

Neoadjuvant chemotherapy proves effective for locally advanced penile squamous cell carcinoma

Study flips treatment paradigm in bilateral Wilms tumor, shows resistance to chemotherapy may point toward favorable outcomes

[Press-News.org] Ultrafast remote switching of light emission