Tag archives: optics
By Hamish Johnston in Beijing
This morning I had a wonderful visit to see some condensed-matter physicists at the Institute of Physics of the Chinese Academy of Sciences (IOP CAS). First I met with theorists Zhong Fang and Hongming Weng and if you know your equations you can see from the above photo that they work on Weyl semi-metals. Fang is deputy director of the institute and is head of a theoretical physics group that includes six faculty members and about 20 postgraduate students. Avid readers might recall that Fang and Weng were named in the Physics World Top 10 Breakthroughs of 2015 for their work on Weyl fermions.
By Matin Durrani
Anyone who gets invited to an event that’s being held on April Fools’ Day is bound to think there’s something fishy going on. But last Friday’s meeting to celebrate the 75th birthday of Bristol University physicist Michael Berry was a genuine commemoration of his career, although it did have its lighter moments.
Grandly entitled “Physics, Art, Mathematics, Science”, the meeting was intended to reflect Berry’s extensive and wide-ranging interests, which stretch from the physics of waves and quantum phenomena to optics, tidal bores and magnetic levitation. (There’s also a phenomenon called the Berry phase, although I understand Berry himself is reluctant to use that term.)
It’s difficult to summarize Berry’s many contributions to physics – he has written approaching 500 papers – so I’m going to take the easy way out and instead point you at his excellent website, where you can easily get lost down lots of entertaining and stimulating rabbit holes.
If there’s one item on his site I can recommend, it’s his description of how his work on the mathematics of magnetic levitation led him to share the 2000 IgNobel Prize for Physics with the future (genuine) Nobel laureate Andre Geim, who in 1997 levitated a frog using a powerful permanent electromagnet while at Bristol.
By Matin Durrani
The April 2016 issue of Physics World magazine is ready and waiting for you to access via our app for mobile and desktop.
Our cover story this month is about Rydberg atoms – those super-sized atoms that are one of the hot topics in condensed-matter physics – and in particular how they could be used to create quantum computers.
You can also find out how virtual-reality tools could help you to learn about the science of optics and learn more about a new research centre at the National Autonomous University of Mexico that’s bringing a fresh approach to the science of complexity.
If you’re a member of the Institute of Physics (IOP), you can now enjoy immediate access to the new issue with the digital edition of the magazine in your web browser or on any iOS or Android mobile device (just download the Physics World app from the App Store or Google Play). If you’re not yet in the IOP, you can join as an IOPimember for just £15, €20 or $25 a year to get full access to Physics World digital.
By Hamish Johnston
Earlier this week I caught the 6.30 a.m. train from Bristol to London to attend the second day of “Unifying physics and technology in light of Maxwell’s equations” at the Royal Society. It was a particularly damp and gloomy morning as I emerged from Piccadilly Circus station and tramped through St James, my sights set on the Duke of York pillar next to the Royal Society in Carlton House Terrace.
It seemed like the perfect morning to be thankful for the light described by James Clerk Maxwell’s equations, and to ponder how they have since illuminated many shadowy corners of physics.
The meeting was organized by three physicists at nearby King’s College London: biophysicist and nanotechnologist Anatoly Zayats; particle physicist John Ellis and condensed-matter physicist Roy Pike. Already, you can see the breadth of physics covered at the meeting.
By Margaret Harris in Glasgow
If you’re the first speaker after lunch at a conference, how do you make sure your audience stays awake and engaged?
For Oliver Ambacher – who occupied the dreaded post-prandial slot during Wednesday’s applied photonics conference at Glasgow’s Technology and Innovation Centre (TIC) – the answer is simple. You pretend to jump off a cliff.
Ambacher, the director of the Fraunhofer Institute for Applied Solid State Physics in Freiburg, Germany, made his leap (actually, several leaps of varying lengths) to illustrate one of the toughest challenges in applied physics: the yawning gap between what academic researchers can provide, and what industry scientists need to turn that research into innovative products. This gap is sometimes called the “valley of death”, and Ambacher’s point was that the risks of leaping across it are generally higher on the industry side. “If I, whose heart is still in physics, jump into the valley of death, I lose funding, maybe a project,” Ambacher explained. “But somebody from industry, they may lose their job. So they cannot jump so far.”
By Margaret Harris
Imagine you’re a veterinarian and a trainer asks you to take a look at a horse. The animal, a champion showjumper, is limping slightly but there is no obvious injury. Exploratory surgery would probably do more harm than good, and the alternative – magnetic resonance imaging (MRI) – isn’t risk-free either. You’d need to put the horse under a general anaesthetic, and you know horses don’t react well to that; in fact, around 0.5% suffer serious injuries while coming round afterwards. And that’s assuming you can even find a scanner big enough to fit a horse. What do you do?
This might sound like a fairly niche dilemma, but for Hallmarq Veterinary Imaging it has become the basis for a thriving business – a business, moreover, that has just won an IOP Innovation Award for the successful application of physics in a commercial product.
At the awards ceremony – which took place last night in the Palace of Westminster, London, just down the hall from the House of Commons chamber – I caught up with Hallmarq’s operations and technical director, Steve Roberts. After sketching out the scenario of the veterinarian and the injured horse, Roberts, a physicist, explained that Hallmarq’s MRI scanner fits around the horse’s leg. This means that equine patients can simply be led into it, sedated but conscious. Sophisticated error-correction and image-processing software helps the scanner compensate for the horse’s movement, and in 15 years of operation, Roberts estimates that veterinarians have used Hallmarq’s machines to scan more than 60,000 horses.
By Matin Durrani
We’re now in the final quarter of the International Year of Light (IYL 2015), which officially launched in January at the headquarters of the UN Educational, Scientific and Cultural Organization (UNESCO) in Paris. You may remember that on the very same day Physics World unveiled its own contribution to the IYL in the form of a free-to-read digital edition containing 10 of our very best feature articles on the science and applications of light.
Today we’re pleased to publish a new version of that digital edition, which contains the same 10 top articles but now includes a series of great videos and a podcast on the theme of light that we’ve been busy creating over the last few months. The refreshed digital edition also has interviews with some of the people involved in the IYL, in which they highlight some of the successes of the year so far and examine the legacy the IYL will leave behind. Click here to find out more.
By Matin Durrani
Sometimes, nature does something unexpected – something so rare, transient or remote that only a lucky few of us get to see it in our lifetimes. In the July issue of Physics World, we reveal the physics behind our pick of the weirdest natural phenomena on our planet, from dramatic rogue waves up to 30 m tall, to volcanic lightning that can be heard “whistling” from the other side of the world, and even giant stones that move while no-one is watching. We also tackle tidal bores on rivers and the odd “green flash” that is sometimes seen at sunset.
Plus, we’ve got six fabulous full-page images of a range of weird phenomena, including salt-flat mirrors, firenadoes, “ice towers”, beautifully coloured nacreous clouds, mysterious ice bubbles of gas trapped in columns, as well as my favourite – the delicately wonderful “frost flowers” seen very occasionally on plants.
By Matin Durrani
The focus issue, which can be read here free of charge, kicks off by looking at the giant laser interferometers underpinning the latest searches for gravitational waves. We also report on recent efforts to use optical instead of radio waves for satellite communication and have an interview with Ian Walmsley from the University of Oxford about the vital role that optics and photonics play in the UK’s new £270m Quantum Technologies Programme.