Welcome Physics World  August 2021

Hammers and nails

As a geophysicist at Sandia National Laboratories in the US, Rob Abbott was looking for ways to distinguish natural seismic events from underground nuclear tests when he came across a technique called distributed acoustic sensing (DAS). Invented during the telecoms boom of the 1990s, and subsequently refined by scientists in the oil and gas industry (among others), DAS essentially transforms ordinary fibre-optic cables into giant, kilometres-long listening devices. Initially, Abbott was sceptical about whether DAS would work for his application, but when the results exceeded his expectations, he became an enthusiast. “It was like I had a new hammer and I was looking for nails sticking up,” he recalls.

Abbott’s next “nail” is the subject of an interview in this Physics World Instrumentation & Vacuum Briefing, and other scientists whose work appears in these pages tell similar tales. As Martin Weides explains (‘From customer to consultant’), hardware improvements have also created new opportunities in quantum computing. For example, when larger and more powerful cryostats entered the market, Weides, a physicist at the University of Glasgow, UK, observes that it suddenly became possible to cool more than a teacup-sized volume of space. That extra bit of elbow-room proved crucial in building quantum computers based on superconducting qubits, as these qubits must be kept at temperatures just above absolute zero and the computers become more capable as the number of qubits increases.

Sometimes, developing better “hammers” means making the hardware smaller, not bigger. Spectrometers that operate at visible, near and short-wave infrared wavelengths are routinely used in studies of atmospheric science, ecology, geology, agriculture and forestry, but their large size makes it hard to deploy them on small satellites or drones. Researchers led by Ronald Lockwood of the Massachusetts Institute of Technology in the US are working to change that by slimming down their spectrometer’s optics (‘Imaging spectrometer slims down’). A group at NASA’s Goddard Space Flight Center is similarly hard at work on shrinking the dewars used to cool the mirrors on balloon-borne telescopes (‘Balloon-borne telescopes keep cool with less’). Back in the quantum world, physicists at the US National Institute of Standards and Technology have reduced the size of the magneto-optical traps that keep atoms cold and isolated from their surroundings (‘Streamlined optics pave the way for miniature atom traps’) – a vital step towards making cold-atom-based quantum devices small enough to be portable.

None of the innovations in this Briefing have come easily. Some, such as advances in vacuum technology that could make battery production faster and more energy-efficient (‘Process innovations benefit battery manufacture’), are still a work in progress. But in each case, the message is clear: once you have the right tools, a whole world of possibilities comes into focus.