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

The analogue of a tsunami for telecommunication

2013-12-27
(Press-News.org) Contact information: Ilya Usov
science-release@rector.msu.ru
Lomonosov Moscow State University
The analogue of a tsunami for telecommunication Development of electronics and communication requires a hardware base capable for increasingly larger precision, ergonomics and throughput. For communication and GPS-navigation satellites, it is of great importance to reduce the payload mass as well as to ensure the signal stability. Last year, researchers from the Moscow State University (MSU) together with their Swiss colleagues from EFPL performed a study that can induce certain improvements in this direction. The scientists demonstrated (this paper was published in Nature Photonics) that the primary source of noise in microresonator based optical frequency combs (broad spectra composed of a large number of equidistant narrow emission lines) is related to non-linear harmonic generation mechanisms rather that by fundamental physical limitations and in principle reducible.

On December 22st, a new publication in Nature Photonics is appearing where they extend their results. Michael Gorodetsky, one of the co-authors of this paper, professor of the Physical Faculty of MSU affiliated also in the Russian Quantum Centre in Skolkovo, says that the study contains at least three important results: scientists found a technique to generate stable femtosecond (duration of the order of 10-15 seconds) pulses, optical combs and microwave signals.

Physicists used a microresonator (in this particular case, a millimeter-scale magnesium fluoride disk was used, where whispering-gallery electromagnetic oscillations may be excited, propagating along the circumference of the the resonator) to convert continuous laser emission into periodic pulses of extremely short duration. The best known analogous devices are mode-locked lasers that generating femtosecond, high-intensity pulses. Applications of these lasers range from analysis of chemical reactions at ultra-short timescales to eye-surgery.

"In mode-locked femtosecond lasers complex optical devices, media and special mirrors are normally used. However we succeeded in obtaining stable pulses just in passive optical resonator using its own non-linearity," -- Gorodetsky says. This allows, in future, to decrease drastically the size of the device.

The short pulses generated in the microresonator are in fact what is known as optical solitons (soliton is a stable, shape-conserving localized wave packet propagating in a non-linear medium like a quasiparticle; an example of a soliton existing in nature is a tsunami wave). "One can generate a single stable soliton circulating inside a microresonator. In the output optical fiber, one can obtain a periodic series of pulses with a period corresponding to a round trip time of the soliton." -- Gorodetsky explains.

Such pulses last for 100-200 femtoseconds, but the authors are sure that much shorter solitons are achievable. They suggest that their discovery allows to construct a new generation of compact, stable and cheap optical pulse generators working in the regimes unachievable with other techniques. In the spectral domain, these pulses correspond to the so-called optical frequency "combs" that revolutionized metrology and spectroscopy and brought to those who developed the method a Nobel Prize in physics in 2005 ( American John Hall and German Theodor Haensch received the Prize "for their contributions to the development of laser-based precision spectroscopy, including the optical frequency comb technique"). Currently existing comb generators are much larger and more massive.

At the same time, as the scientists show, a signal generated by such a comb on a photodetectors a high-frequency microwave signal with very low phase noise level. Ultra-low-noise microwave generators are extremely important in modern technology; they are used in metrology, radiolocation, telecommunication hardware, including satellite communications. Authors note that their results are critical for such applications as broadband spectroscopy, telecommunications, and astronomy.

### END


ELSE PRESS RELEASES FROM THIS DATE:

Study: Some plants may not adapt quickly to future climate change

2013-12-27
Study: Some plants may not adapt quickly to future climate change GAINESVILLE, Fla. --- Using the largest dated evolutionary tree of flowering plants ever assembled, a new study suggests how plants developed traits to withstand low temperatures, with implications ...

Solitons in a crystal

2013-12-27
Solitons in a crystal Soliton water waves can travel several kilometers without any significant change in their shape or amplitude, as opposed to normal waves, which widen as they travel, and eventually disappear. Discovered over 150 years ...

Annals of Internal Medicine tip sheet for Dec. 24, 2013

2013-12-27
Annals of Internal Medicine tip sheet for Dec. 24, 2013 Embargoed news from Annals of Internal Medicine 1. Unprecedented but Justified. Princeton meningitis outbreak calls for "compassionate use" of unlicenced vaccine In the wake of Princeton University's ...

In men, high testosterone can mean weakened immune response, Stanford study finds

2013-12-27
In men, high testosterone can mean weakened immune response, Stanford study finds STANFORD, Calif. — Scientists at the Stanford University School of Medicine have linked high testosterone levels in men to a poor immune response to an influenza ...

Higher mortality in postmenopausal women with RA and anti-CCP antibodies

2013-12-27
Higher mortality in postmenopausal women with RA and anti-CCP antibodies New research shows mortality rates are two times higher in postmenopausal women with rheumatoid arthritis (RA) and anti-cyclic citrullinated peptide (anti-CCP) antibodies. Findings published in the American ...

Acupuncture, real or sham, eases hot flashes due to breast cancer chemo

2013-12-27
Acupuncture, real or sham, eases hot flashes due to breast cancer chemo Both real and sham weekly acupuncture treatments eased hot flashes and other side effects of anticancer drug treatment in a small, preliminary study of breast cancer patients, Baltimore researchers ...

Both real and 'sham' acupuncture help ease side effects of widely used breast cancer drug

2013-12-27
Both real and 'sham' acupuncture help ease side effects of widely used breast cancer drug University of Maryland School of Medicine researchers found patients experienced improvement in hot flashes, other symptoms BALTIMORE – December ...

Study shows value of calcium scan in predicting heart attack, stroke among those considered at risk

2013-12-27
Study shows value of calcium scan in predicting heart attack, stroke among those considered at risk Coronary artery calcium testing trumps cholesterol levels, high blood pressure and other risk factors in predicting heart attacks and deaths A new study shows ...

Researchers identify gene that influences the ability to remember faces

2013-12-27
Researchers identify gene that influences the ability to remember faces New findings suggest the oxytocin receptor, a gene known to influence mother-infant bonding and pair bonding in monogamous species, also plays a special role in the ability to remember faces. ...

Inosine treatment safely elevates urate levels in Parkinson's disease patients

2013-12-27
Inosine treatment safely elevates urate levels in Parkinson's disease patients Phase 2 trial supports further investigation of urate's ability to slow disease progression A clinical trial assessing the potential of the nutritional supplement inosine to ...

LAST 30 PRESS RELEASES:

'Arctic Monkeys': Early primates survived in cold climates, not tropical forests

How do cells prevent premature protein release? UIC study cracks the case

Study demonstrates excellent potential of earthquake early warning system in Alaska

Wild chimpanzees learn how to communicate from relatives on mom’s side, not dad’s

Kids of obese parents more likely to develop obesity due to inheriting related genes

Mothers’ genes may shape children’s weight - even without being passed down

Zhou receives funding for novel performance profiling & analysis infrastructure for scientific deep learning workloads

Sleeter receives funding for revolutionary war teaching guides

Nature-inspired coding: dynamic laws of multispectral camouflage

Digital-coded metasurfaces: A comprehensive review of the new paradigm in wireless communication

Early pilot and prior studies point to increased butyrate and reduced spirochete signals; Tharos advances controlled veterinary trials

Action curiosity algorithm boosts autonomous navigation in uncertain environments

New study raises questions about how Ozempic affects muscle size and strength

Racial differences in screening eligibility by breast density after state-level insurance expansion

Rapid access to emergency medical services within historically redlined areas

Findings show NT’s vital water source is drying – and it can be seen from space

Dancing against the current: Microbial survival strategy

New insights into tectonic movements in south-eastern Europe

EMBARGOED until 00:01 AEST, 6 August 2025: Great Barrier Reef more volatile with sharp declines in coral cover

Solving a dirty problem with sunlight and oil

Lupus Research Alliance announces 2025 Empowering Lupus Research Award recipients to support breakthroughs

New survey maps hundreds of satellite systems orbiting dwarf galaxies

Treatment for obstructive sleep apnea lowers heart risk for some patients, increases risk for others

Extinction in Macaronesia

Yonsei University researchers develop deep learning model for microsatellite instability-high tumor prediction

Machine learning-based design enables more efficient wireless power transfer

Beyond pesticides: Discovering nature's own pest control with bush basil companion plants

An ancient predator’s shift in diet offers clues on surviving climate change

How can visual artists protect their work from AI crawlers? It’s complicated

Progress toward a population screening test for COPD

[Press-News.org] The analogue of a tsunami for telecommunication