KATRIN experiment places upper limit on the mass of the neutrino

14 Feb 2022

Physicist Björn Lehnert from the Lawrence Berkeley National Laboratory talks to Richard Blaustein about what a new precise measurement of the neutrino means for particle physics

Weighty matters: physicist Björn Lehnert works on the Karlsruhe Tritium Neutrino Experiment at the Karlsruhe Institute for Technology in Germany. He performed parts of the analysis using the Cori supercomputer at Berkeley Lab’s National Energy Research Scientific Computing Center. (Courtesy: Björn Lehnert)

Based at the Lawrence Berkeley National Laboratory in the US, Björn Lehnert is a neutrino physicist who originally did a PhD at the Technische Universität Dresden in Germany on the GERDA experiment.

 

Deep learning identifies head-on collisions in LHC data

23 Jun 2022

Sensory overload: simulation of a proton-proton collision at the Large Hadron Collider. (Courtesy: CERN)

Deep learning could hold the key to making sense of proton collisions generated in the world’s premier particle accelerator. That is the message from physicists in Europe and the US who have shown how an algorithm developed for language translation can efficiently filter out noise from data taken by detectors at at CERN’s Large Hadron Collider.

 

How climate change is affecting human and natural systems, test your knowledge of artificial intelligence

30 Jun 2022 Hamish Johnston

In this episode of the Physics World Weekly podcast we explore how climate change is affecting human and natural systems with Noah Diffenbaugh, who leads the Climate and Earth System Dynamics Group at Stanford University in California.

 

Wearable MEG system evaluates epilepsy in children

06 Jun 2022

A better fit: Non-epileptic child with the wearable OPM set-up used in the study (left). OPMs fixed onto a conventional EEG cap using homemade 3D-printed mounts sewn onto the cap (right). (Courtesy: Odile Feys)

Optically-pumped magnetometers (OPMs) are a promising emerging technology that could make magnetoencephalography (MEG) more accurate and tolerable for patients who have difficulty remaining motionless while the exam is performed – such as young children.

 

The glass that offers Ukraine hope: Oksana Kondratyeva on the interface between art, science and architecture

23 Jun 2022 James Dacey

Taken from the June 2022 issue of Physics World. Members of the Institute of Physics can enjoy the full issue via the Physics World app.

Art of the matter An example of some of Ukrainian glass artist Oksana Kondratyeva’s work, which was created using a hydrofluoric-acid-etched flashed glass technique. (Courtesy: Oksana Kondratyeva)

Just three days before the 1986 Chernobyl disaster, the power plant’s administrative building received a splash of colour. A nine-part stained-glass series was installed depicting the history of humankind’s relationship with energy, from Prometheus stealing fire from the gods, to scientists splitting the atom.

 

Quantum approximate optimization algorithm can be implemented using Rydberg atoms

14 Apr 2022

Quantum optimization team: from left to right are Kilian Ender, Clemens Dlaska, Wolfgang Lechner, Rick van Bijnen, Andreas Kruckenhauser and Glen Bigan Mbeng

Quantum computers are often discussed as a technology of the future, but many devices exist already. Because there is no consensus on a single, universal quantum computer design, however, determining the best use for each existing device can be daunting. Recently, researchers at the University of Innsbruck in Austria started to address part of that question by proposing a new way to implement a quantum optimization algorithm by using extremely cold atoms.

 

Bridging the knowledge gap on AI and machine-learning technologies

22 Jun 2022

Medical physicists explored a range of education and training scenarios for AI and machine learning at last month’s ESTRO Annual Congress

ESTRO 2022: Every radiotherapy physicist should know about AI/machine learning…but how much? (Courtesy: iStock/imaginima)

How much is enough? How much is too much? These are questions that cut to the heart of a complex issue currently preoccupying senior medical physicists when it comes to the training and continuing professional development (CPD) of the radiotherapy physics workforce.

 

NHS England’s investment in big data insights will fast-track innovation in radiation oncology

29 Jun 2022 Sponsored by Elekta

Elekta’s cloud-based software platform ProKnow is being used to centralize NHS England’s radiotherapy data while simultaneously opening up access to that data among treatment centres across the country

Data science: John Byrne, deputy head of radiotherapy physics at the Northern Centre for Cancer Care, is among the early-adopters of ProKnow within NHS England, aggregating and mining big data sets comprising hundreds or thousands of treatment plans. (Courtesy: Freeman Hospital)

Precision radiation medicine specialist Elekta has shifted through the gears this year, accelerating the commercial and clinical exploitation of ProKnow, a dedicated suite of cloud-based software tools that enables regional and national networks of radiation oncology clinics to aggregate, structure and interrogate their diverse, and previously fragmented, data stores.

 

Reducing metal artefacts in photon-counting CT

29 Jun 2022

Hip phantom images: In CT slices of a hip phantom, no optimal keV setting could be found to effectively reduce metal artefacts. Adding iterative metal artefact reduction (iMAR) strongly reduced the base artefact level for all energies. (Courtesy: J A Anhaus et al Phys. Med. Biol. 10.1088/1361-6560/ac71f0)

Metal implants in the body, such as hip replacements or dental fillings, are a major source of artefacts in CT images. Clinically available methods reduce these metal artefacts – up to a point.

 

Machine learning could minimize quantum tunnelling in transistors

22 Jun 2022

Ever shrinking: a study of the interface between silicon and silicon dioxide could lead to smaller transistors. (Courtesy: iStock/Quardia)

Two researchers in China have shown how unwanted quantum tunnelling in field-effect transistors (FETs) could be suppressed by controlling the lattice orientations of materials used in the devices. Using machine learning to analyse thousands of candidate orientations, Ye-Fei Li and Zhi-Pan Liu at Fudan University in Shanghai identified two stable configurations that minimize tunnelling.

 

Simulations show that asteroid impacts would destroy evidence for relic shorelines on Mars

30 Jun 2022

Current debate: some claim that certain features on Mars are ancient shorelines – a central plank in the argument that oceans had graced the Red Planet billions of years ago. (Courtesy: ESO/M Kornmesser)

If ancient shorelines exist on Mars, they would be largely scoured from view by billions of years of asteroid impacts. That is according to a new study by researchers in the US, who used computer modelling to simulate eons of cratering on the Martian surface.

 

South African robotic telescope to begin search for the afterglow of cosmic events

25 Jun 2022

Eye on the sky The BOOTES 6 telescope at the Boyden Observatory in Bloemfontein will search for transient events. (Courtesy: Emilio Jesus Carcia)

A new optical telescope in South Africa that will measure the brightness of transient sources will begin operation in mid-July. Located at the Boyden Observatory in Bloemfontein, the telescope – a collaboration between South Africa’s University of the Free State, University College Dublin (UCD) and the Institute of Astrophysics of Andalusia in Spain – will be used to study the afterglow from extremely energetic astrophysical events.

 

Water harvesting gel works at low humidity levels

20 Jun 2022

Soaking it up: the new polymer gel can harvest moisture from relatively dry air. (Courtesy: University of Texas at Austin)

Researchers in the US have designed a sustainable polymer gel that can harvest large quantities of water from the surrounding air, even in low-humidity conditions. Created by Youhong Guo and colleagues at the University of Texas at Austin, the low-cost material combines water-absorbing plant fibres with cellulose, which expels water when heated.

 

Researchers use 3D printing to grow full-thickness skin in the lab

30 Nov 2021

Fabrication of a double-layered skin model using human dermal fibroblasts (HDFs) and an immortal human keratinocyte cell line (HaCaTs). (Courtesy: Biofabrication 10.1088/1758-5090/ac2ef8)

Skin is the body’s first line of defence against toxins, radiation and harmful substances. It has at least six functions, regenerates itself approximately once each month, and consists of up to seven layers of tissue.

 

‘Nanotwinning’ produces stronger metals

21 Jun 2022 Isabelle Dumé

How the tiny crystalline grains that make up most solid metals actually form. (Courtesy: Christopher Schuh, Keith Nelson, and James LeBeau)

When steel, aluminium and other widely used metals or alloys pass through industrial processes such as machining, rolling and forging, their nanoscale structure undergoes dramatic changes. Extremely fast production processes make it difficult to analyse these changes due to the sheer speed and small scale at which they take place, but researchers at the Massachusetts Institute of Technology (MIT) in the US have now succeeded in doing exactly that, pinning down what happens as crystal grains form in the metal under extreme deformation at the nanoscale.

 

IUPAP: uniting physicists for the last 100 years

27 Jun 2022 Laura Hiscott

Michel Spiro, president of the International Union of Pure and Applied Physics (IUPAP), talks to Laura Hiscott about the organization’s biggest achievements, its centenary celebrations, and its future

Future outlook Michel Spiro is president of the International Union of Pure and Applied Physics, which is celebrating its centenary this year with a series of events. (Courtesy: CERN/Maximilien Brice)

Can you remind us of IUPAP’s remit?

IUPAP is a global organization that was founded in 1922. Its mission is to assist the worldwide development of physics, to foster international co-operation in physics and to help in the application of physics towards solving problems of concern to humanity.

 

Continuous Bose–Einstein condensate opens the door to continuous-wave atom lasers

18 Jun 2022

Continuous BEC: the experimental setup at the University of Amsterdam. (Courtesy: Florian Schreck)

A continuous Bose–Einstein condensate (BEC) has been produced by researchers in the Netherlands. Claimed as a first, the achievement has been sought for years and could lead to continuous-wave atom lasers and a more fundamental understanding of the physics of condensed matter.

 

Xanadu puts quantum advantage in the cloud

27 Jun 2022 Naomi Solomons

How it works: A schematic of the experiment, showing (from left to right) the photon source, fibre-based loops of different sizes with programmable parameters, and a demultiplexer that sends the outputs to different photon-number-resolving (PNR) detectors. (Courtesy: Xanadu)

Researchers at Xanadu, a Canadian company specializing in photonic quantum computing, claim to have achieved quantum computational advantage with an experiment run on their cloud-accessible Borealis machine.

 

Seeking the warm glow of the Unruh effect, reconfigurable hardware drives innovation in test and measurement

16 Jun 2022 Hamish Johnston

In this episode of the Physics World Weekly podcast the physicist and entrepreneur Daniel Shaddock explains how building gravitational-wave detectors inspired him to co-found a company that takes a novel approach to creating test and measurement equipment. Shaddock is CEO of Liquid Instruments, and he explains how the firm uses field programmable gate arrays to create instruments that can be reconfigured for a wide range of uses.

 

A new approach to Hall effect measurements for researchers

28 Jun 2022 Sponsored by Lake Shore Cryotronics

The All-in-one Hall analysis instrument from Lake Shore Cryotronics delivers significantly higher levels of precision, speed, and convenience

This video looks at the MeasureReady™ M91 FastHall™ measurement controller, an all-in-one Hall analysis instrument from Lake Shore Cryotronics that delivers significantly higher levels of precision, speed, and convenience to researchers involved in the study of electronic materials.

 

Telescopes, accelerators and LIGO team up to probe neutron stars

19 Jun 2022

Cataclysm: Artist’s illustration of two merging neutron stars. (Courtesy: NSF/LIGO/Sonoma State University/A. Simonnet)

Physicists have created a framework for better understanding the super-dense matter inside neutron stars by combining observations from gravitational-wave detectors and conventional telescopes with experimental results from particle accelerators.

 

Gravitational waves from merging black-hole ‘atom’ could reveal new particles

21 Jun 2022

Atomic transition Kinks in the gravitational-wave signal from merging black holes could reveal the presence of ultralight bosons. (Courtesy: LIGO/T Pyle)

Evidence for a new type of subatomic particle could be lurking within the gravitational waves produced by some merging black holes, according to calculations by physicists in the US and the Netherlands. John Stout at Harvard University and colleagues have studied a process whereby a cloud of hypothetical ultralight bosons could form around a black hole, creating a “gravitational atom”.

 

Flexible organic LED produces ‘romantic’ candle-like light

29 Jun 2022 Isabelle Dumé

A bendable organic LED with a natural mica backing releases a strong, candlelight-like glow. (Courtesy: Andy Chen and Ambrose Chen)

A new bendable organic light-emitting diode (OLED) that produces warm, candle-like light with hardly any emissions at blue wavelengths might find a place in flexible lighting and smart displays that can be used at night without disrupting the body’s biological clock. The device, which is an improved version of one developed recently by a team of researchers from National Tsing Hua University in Taiwan, is made from a light-emitting layer on a mica substrate that is completely free of plastic.

 

A glassy solution to nuclear waste

22 Jun 2022

Taken from the June 2022 issue of Physics World. Members of the Institute of Physics can enjoy the full issue via the Physics World app.

Ancient glass is not just of interest to historians and archaeologists – it may also hold the key to understanding the durability of vitrified nuclear waste. Rachel Brazil investigates

Molten hot To vitrify radioactive waste, it's incorporated into molten glass. (Courtesy: US Dept. of Energy / Science Photo Library)

The golden death mask of the pharaoh Tutankhamun is one of the most famous historical artefacts in the world. The shining visage of the young king dates back to around 1325 BCE and features blue strips that are sometimes described as lapis lazuli.

ΜΕΡΙΚΕΣ ΑΠΟΨΕΙΣ ΓΙΑ ΤΗΝ ΥΠΑΡΞΗ ΑΡΝΗΤΙΚΗΣ ΜΑΖΑΣ ΣΧΕΣΗ ΑΡΝΗΤΙΚΗΣ ΜΑΖΑΣ ΜΕ ΤΗΝ ΥΠΟΘΕΣΗ ΤΗΣ ΣΚΟΤΕΙΝΗΣ ΥΛΣ ΚΑΙ ΣΚΟΤΕΙΝΗΣ ΕΝΕΡΓΕΙΑΣ

 ΜΕΡΙΚΕΣ ΑΠΟΨΕΙΣ ΓΙΑ ΤΗΝ ΥΠΑΡΞΗ ΑΡΝΗΤΙΚΗΣ ΜΑΖΑΣ ΣΧΕΣΗ ΑΡΝΗΤΙΚΗΣ ΜΑΖΑΣ ΜΕ ΤΗΝ ΥΠΟΘΕΣΗ ΤΗΣ ΣΚΟΤΕΙΝΗΣ ΥΛΣ ΚΑΙ ΣΚΟΤΕΙΝΗΣ ΕΝΕΡΓΕΙΑΣ 

Κάνουμε την υπόθεση ότι η θετική μάζα και η αρνητική μάζα γεννήθηκαν ταυτόχρονα μαζί με την αρχή του Σύμπαντος Αυτό που ικανοποιεί τα διάφορα προβλήματα που παρουσιάζουν η σκοτεινή ύλη και η σκοτεινή ενέργεια, όπως η κεντρομόλος επίδραση δυνάμεων γαλαξιών και σμηνών γαλαξιών, από προηγούμενη σκοτεινή ύλη, επιδράσεις μαζών που είναι ανάλογες με την απόσταση r, απωστικές δυνάμεις που απαιτούνται για την διαστολή, σκοτεινή ενέργεια με θετικές τιμές, χαμηλές αλληλεπιδράσεις όταν συμβαίνουν συγκρούσεις σκοτεινής ύλης, επιβράδυνση της διαστολής και της επιτάχυνση της διαστολής του Σύμπαντος, σχηματισμός κενού, μηχανισμός διαστολής, πρόβλημα λεπτής ρύθμισης της πυκνότητας της μάζας, σύγκρουση μεγάλου αριθμού μαζών, Σύμπαν, ηλικία και μέγεθος του σύμπαντος.

 

New benchmark set for magnetic monopole searches

16 Jun 2022

True north: schematic representation of a magnetic monopole and its field lines. (Courtesy: Kavli IPMU)

A new benchmark has been set in the search for hypothetical magnetic monopoles produced in the atmosphere through collisions with incoming cosmic rays. Using simulations, a team led by Volodymyr Takhistov at the University of Tokyo compared data gathered by experiments searching for monopoles with the signals that are expected to be produced by cosmic-ray collisions. This allowed the team to set new limits on the existence of magnetic monopoles.

 

Atmospheric helium levels are on the rise

17 Jun 2022 Isabelle Dumé

Levels of helium-4 in the Earth’s atmosphere have been increasing since at least 1974, according to a study by researchers at the University of California, San Diego, US that resolves a longstanding anomaly in atmospheric science.

Study lead author Benjamin Birner of Scripps Institution of Oceanography at UC San Diego. (Courtesy: Erik Jepsen/UC San Diego)

Helium-4, the most abundant isotope of helium, is produced by radioactive decay in the Earth’s crust and accumulates in small amounts in natural gas. When the gas is extracted and burned, the helium is released into the atmosphere. Theoretical calculations have therefore suggested that atmospheric levels of helium-4 must have been increasing for decades due to fossil fuel usage. Until now, however, convincing experimental evidence for such a build-up had been lacking.

 

Microwave metasurface is reconfigured using stepping motors

23 Feb 2022

Gearing up: on the left is an illustration of a 4×4 array of meta-atoms that are rotated using gears and a stepping motor. On the right is a single meta-atom at the centre of rings that illustrate its effect on phase and polarization. (Courtesy: Xu et al./Advanced Photonics)

A metasurface that can be reconfigured using electric motors has been designed by researchers in the US and China. The structure can be programmed in real time to control impinging electromagnetic waves and was developed by a team led by Weili Zhang at Oklahoma State University. The metasurface comprises an array of dielectric “meta-atoms”, which can be reoriented in groups. The set-up enabled the team to use the device to perform three very different tasks that involved manipulating microwaves.

 

Climate change affects cherry blossoms, satisfying sizzle gives cooking temperature

17 Jun 2022 Hamish Johnston

Sure sign of spring: cherry blossoms in Japan. (Courtesy: Yae Yamamoto/CC BY-SA 4.0)

Around the world from Kyoto to Washington DC, people enjoy the blossoming of cherry trees as a rite of spring. In some places – notably Japan and South Korea – blossom festivals are vital for local economies, so it is important that organizers get their timings right.

 

Advanced algorithm predicts outcome for patients with severe brain injury

17 Jun 2022

Guiding patient care: Predicting long-term clinical outcomes is challenging in patients with severe TBI because of their comatose status and concerning imaging features such as cerebral oedema and intracranial haemorrhage. But many such patients have potential to make a favourable recovery. (Courtesy: iStock/Sutthaburawonk)

A team of US-based researchers has created an innovative deep-learning model that analyses CT scans and clinical information to predict six-month outcomes for patients with severe traumatic brain injury (TBI). In addition to outperforming the predictions of neurosurgeons, the algorithm can also accurately steer TBI patients towards life-saving care.

Seeking the warm glow of the Unruh effect, reconfigurable hardware drives innovation in test and measurement

16 Jun 2022 Hamish Johnston

In this episode of the Physics World Weekly podcast the physicist and entrepreneur Daniel Shaddock explains how building gravitational-wave detectors inspired him to co-found a company that takes a novel approach to creating test and measurement equipment. Shaddock is CEO of Liquid Instruments, and he explains how the firm uses field programmable gate arrays to create instruments that can be reconfigured for a wide range of uses.

 

Quantum effects help make DNA unstable

14 Jun 2022 Isabelle Dumé

It is only now that the DNA bond modification process has been accurately quantified, and its quantum element understood. (Courtesy: Shutterstock/ymgerman)

Quantum effects play a hitherto unexpected role in creating instabilities in DNA – the so-called “molecule of life” that provides instructions for cellular processes in all living organisms. This conclusion, based on work by researchers at the University of Surrey in the UK, goes against long-held beliefs that quantum behaviour is not relevant in the wet, warm environment of cells, and could have far-reaching consequences for models of genetic mutation.

 

Multi-tasking microneedle sensor tracks glucose, alcohol and lactate levels in real time

13 Jun 2022

Cost-effective design: The microneedle sensor patch contains two primary components: the disposable sensor array (right) and reusable electronics. (Courtesy: Laboratory for Nanobioelectronics/UC San Diego)

Wearable sensors that monitor biomarkers in biofluid just under the surface of the skin – wirelessly, painlessly and in real-time – could be of wide medical benefit. Such devices could measure glucose for diabetes management, for example, support the individualization of prescription drug dosing and automatic drug delivery, or even monitor alcohol levels in the body.

 

Slowest ever neutron star is found in cosmic graveyard

14 Jun 2022

Slow going Artist’s impression of the signal from PSR J0901–4046 is shown in magenta. Shown in blue are signals from other, faster pulsars. (Courtesy: Danielle Futselaar/artsource.nl)

An unusual pulsating radio signal emerging from a “stellar graveyard” could be evidence for a new class of neutron star, according to an international team of scientists. The pulsar signal comes from a 53 million-year-old neutron star rotating once every 76 s  – making this the slowest rotating neutron star ever observed. The star has been designated PSR J0901-4046 and was found by the MeerKAT radio telescope in South Africa.

 

Gaia releases most detailed maps of the Milky Way ever taken

13 Jun 2022 Michael Banks

Starstruck: A collage of four different Gaia maps: the speed at which stars move towards or away from us (top left); 3D motions of stars (bottom left); interstellar dust (top right); and star metallicity (bottom right). (courtesy: ESA/Gaia/DPAC)

The European Space Agency (ESA) has released the latest data from its €450m Gaia mission. It contains information about billions of stars in our Milky Way, a catalogue of thousands of objects in our solar system such as asteroids and moons, as well as data on millions of galaxies and quasars in the universe.

100% Αποτέλεσμα! Ρόφημα Για Αποτοξίνωση Του Συκωτιού & Χολής! | Ακαδημία Υγείας

 

100% Αποτέλεσμα! Ρόφημα Για Αποτοξίνωση Του Συκωτιού & Χολής! | Ακαδημία Υγείας

ΤΑ ΣΥΣΤΑΤΙΚΑ ΤΟΥ ΡΟΦΗΜΑΤΟΣ

Αρχικά θα ήθελα να αναφέρω τα συστατικά που περιλαμβάνει το ρόφημα και έπειτα να δούμε τον τρόπο έκτελεσης του ροφήματος. Επιπλέον θα δούμε τις τροφές που βοηθούν στην αποτοξίνωση του ήπατος και το διατηρούν σε υγιή κατάσταση.

 

Weather satellite sheds light on ‘Great Dimming’ of Betelgeuse star

08 Jun 2022

Great dimming: Betelgeuse as seen by the SPHERE instrument on ESO’s Very Large Telescope in January and December 2019. (Courtesy: ESO/M Montargès et al.)

A weather satellite has helped explain why the red supergiant star Betelgeuse experienced an unprecedented dimming in 2019–2020.

 

Bleximo builds its competitive advantage with an application-specific approach

10 Jun 2022 Sponsored by Bleximo

The key to achieving ‘quantum advantage’ lies in the co-design of algorithms and hardware for a new generation of superconducting quantum computers

Full-stack quantum computing: Bleximo’s holistic approach to product development covers everything from the fundamental physics of superconductors to the software architecture of a deployed quantum computing system. (Courtesy: Bleximo)

California-based start-up Bleximo is betting that its application-specific approach to quantum computing is more efficient – indeed transformative – in addressing highly complex practical problems across a range of industries – from global logistics and aerospace to pharmaceuticals, advanced materials, and energy production and distribution.

 

Lighting up single cells to detect lung cancer earlier

09 Jun 2022 Tami Freeman

Seeing single cells: Paired confocal microscopy (left) and NIR-nCLE (right) images. NIR-nCLE can detect an individual lung cancer cell in a 1:1000 co-culture of malignant and normal cells. (Courtesy: CC BY 4.0/Nat. Commun. 10.1038/s41467-022-30265-z)

When a CT scan highlights a suspicious looking nodule, the next step is to perform a biopsy to rule out malignancy. Current medical technologies, however, cannot provide real-time diagnostic information during biopsy. Instead, samples are sent away for histopathologic analysis, which can take several days. And some nodules may be too small to remove for further testing, leading to uncertainty and patient anxiety, as well as increased costs for further procedures and radiographic surveillance.

 

Polariton condensation emerges from a bound state in the continuum

10 Jun 2022 Kirsty McGhee

Hard at work: Dario Ballarini (left), Vincenzo Ardizzone (centre), and Daniele Sanvitto in their lab. (Courtesy: Daniele Sanvitto/CNR-Nanotec Lecce)

A bound state in the continuum (BIC) is a symmetry-protected topological state that, despite lying in the continuum radiation spectrum of a system, is unable to radiate in the far field. When supported by a photonic crystal, it is characterized by a supposedly infinite lifetime and a remarkable ability to enhance non-linear effects.

 

China released most detailed geological map of the Moon to date

09 Jun 2022 Michael Banks

Courtesy: Science Bulletin 10.1016/j.scib.2022.05.021. © 2022 Science China Press. Reproduced with permission of Elsevier

Scientists in China have released a new geologic map of the Moon that is the most detailed yet. Created by a team led by the Institute of Geochemistry, Chinese Academy of Sciences, the image was made using data from China’s suite of Chang’e lunar exploration missions as well as information from other international organizations.

 

The charge-transport mystery deepens in promising solar-cell materials

08 Jun 2022 Isabelle Dumé

The effective mass of the electrons can be derived from the curvature around the maxima of the ARPES measurement data (image, detail). (Courtesy: HZB)

A longstanding explanation for why perovskite materials make such good solar cells has been cast into doubt thanks to new measurements. Previously, physicists ascribed the favourable optoelectronic properties of lead halide perovskites to the behaviour of quasiparticles called polarons within the material’s crystal lattice. Now, however, detailed experiments at Germany’s BESSY II synchrotron revealed that no large polarons are present. The work sheds fresh light on how perovskites can be optimized for real-world applications, including light-emitting diodes, semiconductor lasers and radiation detectors as well as solar cells.

 

Sapphire fibre makes a robust extreme-environment sensor

08 Jun 2022 Isabelle Dumé

Sapphire optical fibre. (Courtesy: Julian Fells/University of Oxford)

A new single-mode optical fibre made from sapphire rather than the usual silica can withstand temperatures of over 2000°C as well as high levels of radiation. Although the fibre’s length is currently limited to 1 cm, its developers at Oxford University, UK, say that the technique they used to construct it could be extended by up to several metres, making it useful for remote sensing in ultra-extreme environments.

 

Using physics to fuel fibre-optic innovation

07 Jun 2022

Taken from the June 2022 issue of Physics World. Members of the Institute of Physics can enjoy the full issue via the Physics World app.

Engineering physicist Christine Tremblay talks to Joe McEntee about the joys of a career spent making fibre-optic networks cheaper, smarter and more resilient, opening the way for telecommunications firms to send voice, data and video streams down hair-thin strands of glass at ever-increasing bit rates

Optical connections Based at the École de technologie supérieure in Montreal, Canada, Christine Tremblay heads up a multidisciplinary team developing real-world optical solutions for telecoms networks. (Courtesy: ÉTS)

For a few early-career scientists, the future is a preordained pathway written in the stars; for others, it seems, the future is just as likely to be found on the back of a grocery-store receipt. Take Christine Tremblay who, in the early 1980s, had just completed the first year of an undergraduate degree in engineering physics at Université Laval, Quebec City, and was all set for a summer job at the Canadian Post Office. It was then that she bumped into one of her lecturers in the local supermarket.

 

New nanosensor targets dopamine

07 Jun 2022

Neurotransmitter: dopamine plays an important role in the function of the brain. (Courtesy: Shutterstock/Phonlamai-Photo)

A sensing technique that can precisely detect the release and diffusion of dopamine from individual neuron release sites has been developed by researchers in Germany. Led by Sebastian Kruss at Ruhr University Bochum, the team created their sensor using specially-modified carbon nanotubes that fluoresce at specific near-infrared wavelengths on contact with dopamine.

 

Experiments with quantum cause and effect reveal hidden nonclassicality

26 May 2022 Jessica Tucker

Exploring cause and effect A photo of the Sagnac interferometer used to generate polarization-entangled photon pairs during a basis measurement. (Courtesy: Davide Poderini/Sapienza University of Rome)

Cause-and-effect explanations like “catnip causes cats to be happy”, “jokes cause laughter” and “exciting research causes Physics World articles” are a useful way to organize knowledge about the world. The mathematics of cause-and-effect underpin everything from epidemiology to quantum physics. In the quantum world, however, the link between cause and effect is not so straightforward. An international team of physicists has now used quantum violations of classical causality to better understand the nature of cause-and-effect. In the process, the team uncovered quantum behaviour in a situation where standard methods indicate that the system ought to be classical – a result that could have applications in quantum cryptography.