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Category: computing – Page 260

Following the path of electronic integrated circuits (EICs), silicon (Si) photonics holds promises to enable photonic integrated circuits (PICs) with high densities, advanced functionality and portability. Although various Si photonics foundries are rapidly developing PIC capabilities—enabling volume production of modulators, photodetectors and most recently lasers—Si PICs have yet to achieve the stringent requirements on laser noise and overall system stability imposed by many applications such as microwave oscillators, atomic physics and precision metrology9,10,11. Semiconductor lasers must strongly suppress amplified-spontaneous-emission noise to achieve narrow linewidth for these applications12. They will also require isolation from the rest of the optical system, otherwise the laser source will be sensitive to back-reflections from downstream optical components that are beyond the control of the PIC designer13. In many integrated photonic solutions, a bulk optical isolator must be inserted between the laser chip and the rest of the system, significantly increasing the complexity, as well as the cost of assembly and packaging14.

To enrich the capabilities of Si PICs and avoid multi-chip optical packaging, non-group-IV materials need to be heterogeneously integrated to enable crucial devices, including high-performance lasers, amplifiers and isolators15,16,17. It has now been widely acknowledged that group III–V materials are required to provide efficient optical gain for semiconductor lasers and amplifiers in Si photonics regardless of the integration architecture, but concerns still remain for a complementary metal–oxide–semiconductor (CMOS) fab to incorporate magnetic materials, which are currently used in industry-standard optical isolators18.

Fortunately, a synergistic path towards ultralow laser noise and low feedback sensitivity exists—using ultrahigh-quality-factor (Q) cavities for lasers that not only reduce the phase noise but also enhance the feedback tolerance to downstream links. These effects scale with the cavity Q and ultrahigh–Q cavities would thus endow integrated lasers with unprecedented coherence and stability19,20. The significance is twofold. First, the direct integration of ultralow-noise lasers on Si PICs without the need for optical isolators simplifies PIC fabrication and packaging. Furthermore, this approach does not introduce magnetic materials to a CMOS fab as isolators are not obligatory for such complete PICs.

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Scientists have discovered a new way to accomplish fast data transmissions through light-emitting diode (LED) bulbs.

While research has progressed in significantly optimizing light-emitting diodes (LEDs), the modulation characteristics of perovskite LEDs remain unclear.

In recent developments, scientists have discovered a new way to transmit data quickly through LEDs. This could allow homes and offices to use the fast internet through lights instead of setting up a wifi router.

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With the summer holiday season now in full swing, the blog will also swing into its annual August series. For most of the month, I will share with you just a small sampling of the colorful videos and snapshots of life captured in a select few of the hundreds of NIH-supported research labs around the country.

To get us started, let’s turn to the study of viruses. Researchers now can generate vast amounts of data relatively quickly on a virus of interest. But data are often displayed as numbers or two-dimensional digital images on a computer screen. For most virologists, it’s extremely helpful to see a virus and its data streaming in three dimensions. To do so, they turn to a technological tool that we all know so well: animation.

This research animation features the chikungunya virus, a sometimes debilitating, mosquito-borne pathogen transmitted mainly in developing countries in Africa, Asia and the Americas. The animation illustrates large amounts of research data to show how the chikungunya virus infects our cells and uses its specialized machinery to release its genetic material into the cell and seed future infections. Let’s take a look.

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The transition to chaos is ubiquitous in nonlinear systems. Continuous-wave-driven photonic-chip-based Kerr microresonators exhibit spatiotemporal chaos, also known as chaotic modulation instability.

For more than fifteen years such modulation instability states have been considered impractical for applications compared to their coherent-light-state counterparts, such as soliton states. The latter have been the centerpiece for numerous high-profile application demonstrations, from long-range to photonic computing.

Now, researchers from the group of Tobias Kippenberg at EPFL have found a new way to harness the unique features of chaotic frequency combs to implement unambiguous and interference-immune massively parallel ranging by utilizing the intrinsic random amplitude and phase modulation of the chaotic comb lines.

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Researchers at the National Institute of Standards and Technology (NIST) have devised a photonic circuit on a chip that transforms a single incoming beam of laser light into a panoply of new beams, each with a host of different optical properties.

The newly generated beams—which retain the frequency of the original beam—simultaneously exit the circuit at different locations along the . That allows scientists and engineers to select the specific characteristics of one or more beams needed for a particular application.

Precision shaping and controlling beams of visible light are critical for diagnosing and studying human diseases, trapping atoms that form the basis of the world’s most , quantum computing, and many other quantum-based technologies.

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Quantum memory that depends on quantum-band integration is a key building block used to develop quantum networks that are compatible with fiber communication infrastructures. Quantum engineers and IT specialists have yet to create such a network with large capacity to form an integrated multimode photonic quantum memory at telecom band.

In a new report in Science Advances, Xueying Zhang and a research team in electronic science, physics, and information technology described fiber-integrated multimode storage of a single photon at telecom band on a laser-written chip.

The storage device made of fiber-pigtailed erbium (Er3+) doped lithium niobate (Er3+:LiNbO3), presented a memory system integrated with telecom-band fiber-integrated on-chip components. The outcomes of the study highlight a pathway for future to come in to being, based on integrated photonics devices.

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Despite that drop, the company did better than expected. Wall Street had forecast it would lose 3 cents a share on an adjusted basis on sales of $12.1 billion, according to Yahoo Finance.

“Our overall position is strengthening,” CEO Pat Gelsinger told analysts, adding later, “simply put, it was a very good quarter.”

Still, he and Chief Financial Officer Dave Zinsner noted that the selling environment was improving only slowly, particularly for server chips.

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The biological roots of autism continue to perplex researchers, despite a growing body of studies looking at an increasing array of genetic, cellular and microbial data. Recently, scientists have homed in on a new and promising area of focus: the microbiome. This collection of microbes that inhabit the human gut has been shown to play a role in autism, but the mechanics of this link have remained awash in ambiguity.

Taking a fresh computational approach to the problem, a study published today, June 26, in Nature Neuroscience sheds new light on the relationship between the microbiome and . This research—which originated at the Simons Foundation’s Autism Research Initiative (SFARI) and involved an innovative reanalysis of dozens of previously published datasets—aligns with a recent, long-term study of autistic individuals that centered on a microbiome-focused treatment intervention. These findings also underscore the importance of longitudinal studies in elucidating the interplay between the microbiome and complex conditions such as autism.

“We were able to harmonize seemingly disparate data from different studies and find a common language with which to unite them. With this, we were able to identify a microbial signature that distinguishes autistic from neurotypical individuals across many studies,” says Jamie Morton, one of the study’s corresponding authors, who began this work while a postdoctoral researcher at the Simons Foundation and is now an independent consultant. “But the bigger point is that going forward, we need robust long-term studies that look at as many datasets as possible and understand how they change when there is a [therapeutic] intervention.”

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Fast data transmissions could be delivered in homes and offices through light-emitting diodes (LED) bulbs, complementing existing communication technologies and networks.

The future’s new internet technologies are being rapidly refined by academics and LED-based communication links are expected to be extensively used in numerous emerging services and scenarios, including Light-fidelity (Li-Fi), underwater communications, moderate-to high-speed photonic interconnects and various “Internet of Things” (IoT) devices.

A new study, published in Nature Photonics and led by the University of Surrey and University of Cambridge, has investigated how to release high-speed photonic sources using . These are semiconductors being researched with LEDs for their excellent optoelectronic properties and low-cost processing methods.

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