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Metallic Hydrogen Claimed CERN Courier April 2017 Sciencewatch C OMPILED BY J OHN S WAIN , N ORTHEASTERN U NIVERSITY Metallic hydrogen claimed It has long been expected that hydrogen Photos of a microscopic becomes metallic under sufficient pressure, sample of hydrogen and researchers have been edging closer to within a circular gasket its production. Now, Ranga Dias and Isaac at increasing pressures, Silvera of Harvard University in the US report showing the transition that they have finally observed the bizarre from a transparent (left) quantum state. Squeezed in a diamond-anvil to opaque (centre) and cell to a pressure of 495 GPa, hydrogen 205 GPa 415 GPa 495 GPa reflective (right) state. becomes a shiny metal with a plasma frequency of 32.5±2.1 eV at a temperature how diamond is formed at high pressures superconducting at room temperature. of 5.5 K – a transition predicted more than and retains its form under normal conditions. 80 years ago by Wigner and Huntington. The If metastable, it could have applications as ● Further reading metal may be metastable, remaining metallic a rocket fuel far more powerful than liquid R Dias and I Silvera 2017 Science DOI: 10.1126/ when the pressure is removed, similarly to hydrogen and oxygen, and may even be science.aal1579. Light Transport Systems Self-mixing Sensor Time crystals Handsteiner of the Institute for Quantum Human–pig genetics Optics and Quantum information in Vienna A major challenge in radiation-intense We offer a compact laser Time crystals are a new form of and colleagues uses light from distant environments is the signal transfer from diode based sensor for detecting non-equilibrium matter that has periodic The first successful human–animal hybrid astronomical sources to produce the settings. the source to the (often expensive and not a small displacement and measuring the motion even in its ground state. Norman Yao has been created: a mixture of human and The work pushes back the most recent time radiation-hard) detection system. Lens-based vibration with an accuracy of better than of the University of California, Berkeley, pig. Jun Wu of the Salk Institute in the US and that any local-realistic influences could light transport systems suffer from aberrations, 300 nm. This easy-to-use sensor can be easily colleagues built on previous work making misalignment and radiation damage. D-Beam used for many purposes including cryogenic and colleagues have published detailed have produced the observed Bell inequality offers optical fibre based light transport chamber vibration detection or referencing the instructions for how to make them and chimeras from mice and rats, and managed to violation by about 16 orders of magnitude, or systems that can replace conventional displacement of wired or translational stages measure their properties, leading two groups put human cells into developing pig embryos. approximately 600 years. lens-based systems. for diagnostics. Moreover, it can also be used to report experimental realisations: J Zhang The embryos were then inserted into adult for velocity measurements of gas-jets and fluid of the University of Maryland and colleagues pigs, which carried them for three to four ● Further reading Amongst others, we are experienced in the targets. Our sensor provides a reliable, low via a chain of trapped ions, and Soonwon weeks, after which they were removed and J Handsteiner et al. 2017 Phys. Rev. Lett. 118 060401. D-Beam, a new spin-off company from the development, optimisation and experimental cost and robust solution that can be used in studied. Although considered controversial, exploitation of synchrotron radiation-based Choi of Harvard University and colleagues, University of Liverpool and the Cockcroft even the harshest environments. via an ensemble of dipolar-spin impurities in the work demonstrates that human cells Institute in the UK provides a range of profile monitors, novel micro mirror array-based Giant quantum computer beam halo monitors for the measurements with diamond. These are the first materials to break can be made to survive and grow inside of reliable and cost-efficient beam diagnostics high dynamic range, and advanced sensor a host animal, bolstering hopes for better for use at accelerator and clinical facilities, D-Beam offers easy-to-use and user time-translation symmetry in a way that is An ambitious proposal suggests that a giant technologies, such as silicon photomultipliers. ways to make organs without the need for friendly diagnostics for charged particle analogous to the breaking of space-translation quantum computer able to solve currently light sources, and reactors for applications human donors. in research, healthcare, security, beams. This includes custom-build diagnostics symmetry in crystals, opening a new chapter computationally unsolvable problems such environment and manufacturing. Beam Loss Monitors (BLM) for your specific needs. We have a wide range in experimental condensed-matter physics. as factoring large numbers could be built of numerical and analytical tools for modelling based on existing technology. Winfried Beam diagnostics is a highly specialised area Based on Fibres and optimising our products for even the most ● Further reading Hensiger of the University of Sussex in where it takes many years to develop a new challenging projects. We have established S Choi et al. 2016 arXiv:1610.08057v1. D-Beam offers BLMs based on fibres with the UK and colleagues propose a football- sensor technology. The first advantage of a collaborative network with universities, unique features compared to the commonly N Yao et al. 2017 Phys. Rev. Lett. 118 030401. field-sized microwave-coupled trapped-ion D-Beam is the availability of a broad range of research centres and industry partners from used BLMs. The fibre-based BLM gathers the J Zhang et al. 2016 arXiv:1609.08684v1. quantum computer using thousands of cutting edge beam diagnostics solutions that all over the world. are not currently offered by any other company. information from the entire beam line you are hand-sized modules, each containing 2500 interested in, and not only one point. Further information can be found at trapped-ion qubits, which could be joined to Secondly, we have the required skilled experts Cosmic Bell test www.d-beam.co.uk make an arbitrarily large computer. To factor to optimise a given diagnostics technology Due to the large number of monitors necessary to cover all beam modules in latest generation Bell’s inequality, which provides a test of a 2048 bit (617 digit)-long number (a task platform towards your specific applications. Alexandra Alexandrova large scale accelerators, it is desirable to whether a system is quantum or classical, impossible on classical computers today) Email: [email protected] find a solution which minimises also the overall is usually derived on the assumption that would need, including error correction, some Telephone: +44(0)1925 864 430 or costs of the system. The use of optical fibres Custom-designed Radiators +44(0)7449 618 935 there are no correlations between the two billion qubit ions, and the calculation in different configurations allows covering experimenter’s choice of measurement would take around 110 days. Quantum We offer radiators for high current/high larger segments of the machines. This allows Prof. Carsten P. Welsch energy beam applications, as well as highly settings or anything else that could causally The observations raise the possibility of computing might start to develop along lines to find new sources or losses and to protect Email: [email protected] sensitive radiators for low intensity beams affect the outcomes. This leaves open the generating transplantable human tissue. similar to experimental high-energy physics the equipment. Telephone: +44(0)1925-864 352 where a small number of particles need to be possibility that an unknown cause affects with large facilities funded by international Or +44(0)7973 247 982 detected. Our radiators can be used for single Our systems provide a resolution of around both the choice of settings and measurements ● Further reading collaborations. Fax: +44(0)1925 864 037 particle detection as well as for beam loss 10 cm, which gives an accurate determination before each trial – typically as little as Jun Wu et al. 2017 Cell 168 473. monitoring applications. They are based on of the loss position. Due to their intrinsic D-Beam microseconds before in experimental tests. ● Further reading the generation of scintillation and Cherenkov design advantages our systems are Keckwick lane, Daresbury laboratory A new “cosmic Bell test” by Johannes B Leksitch et al. 2017 Sci. Adv. 3 e1601540. radiation in different types of optical fibres completely insensitive to magnetic fields Daresbury, Warrington, WA4 4AD and cutting edge photo detectors. and neutron radiation. United Kingdom 15 CCApr17_Sciencewatch.indd 15 08/03/2017 15:28 CERNCOURIER www. V OLUME 5 7 N UMBER 3 A PRIL 2 0 1 7.
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