Nanowerk July 4, 2021 To create thin films of tungsten with unprecedentedly low levels of film stress researchers in Japan have been working with scattering (HiPIMS), a sputtering technique. Using argon gas and a tungsten target, the team looked at how ions with different energies arrived at the substrate over time in unprecedented detail. Instead of using a bias pulse set off at the same time as the HiPIMS pulse, they used their knowledge of when different ions arrived and introduced a tiny delay, 60 microseconds, to precisely select for the arrival of high energy metal ions. They found that […]
Synthetic biology circuits can respond within seconds
MIT News July 1, 2021 A team of researchers in the US (MIT, research org, University of Wisconsin, Penn State College) created a bistable toggle switch in Saccharomyces cerevisiae using a cross-repression topology comprising 11 protein-protein phosphorylation elements. The toggle is ultrasensitive, can be induced to switch states in seconds, and exhibits long-term bistability. They developed a computational framework to search endogenous protein pathways for other large and similar bistable networks. The framework helped them to identify and experimentally verify five formerly unreported endogenous networks that exhibit bistability. Building synthetic protein-protein networks will enable bioengineers to design fast sensing and […]
Ultra-strong squeezing of light demonstrated for ultrafast optical signal processing
Phys.org July 6, 2021 An international team of researchers (Singapore, USA – MIT) succeeded in squeezing light in time by a factor of 11. They demonstrated 3.0× spectral compression of 480 fs pulses while preserving the pulse energy. The strong compression achieved at low powers harnesses advanced on-chip device design, and the strong nonlinear properties of backend-CMOS compatible ultra-silicon-rich nitride, which possesses absence of two-photon absorption and 500× larger nonlinear parameter than in stoichiometric silicon nitride waveguides. By balancing the contributions from the dispersive and nonlinear stages, they could generate strong compression in either time or frequency. The work introduces an […]
Ultrathin semiconductors are electrically connected to superconductors for the first time
Phys.org July 6, 2021 For future applications in electronics and quantum technology, researchers are focusing on the development of new components that consist of monolayer semiconducting material. An international team of researchers (Switzerland, Japan) has demonstrated superconducting vertical interconnect access (VIA) contacts to a monolayer of molybdenum disulfide (MoS2) using MoRe as a contact material. The electron transport was mostly dominated by a single superconductor/normal conductor junction with a clear superconductor gap. They found MoS2 regions that are strongly coupled to the superconductor resulting in resonant Andreev tunneling and junction-dependent gap characteristics, suggesting a superconducting proximity effect. Magnetoresistance measurements showed […]
Unlocking radiation-free quantum technology with graphene
Nanowerk July 8, 2021 Making usable quantum technologies out of rare-earth compounds has remained a challenge because they contain critically radioactive compounds rendering them of limited use in real-world quantum technologies. An international team of researchers (Switzerland, Finland) used the sub-nanometre thickness of graphene to create heavy fermions. By layering thin sheets of carbon on top of one another in a specific pattern, where each sheet is rotated in relation to the other, it is possible to create the quantum properties effect that results in the electrons in the graphene behaving like heavy fermions. While in this work they showed the […]
Top 10 Science and Technology Inventions for the Week of July 2, 2021
01. ‘Edge of chaos’ opens pathway to artificial intelligence discoveries 02. Backscatter breakthrough runs near-zero-power IoT communicators at 5G speeds everywhere 03. A crystal made of electrons 04. A new piece of the quantum computing puzzle 05. Non-stop signal achieved in high-power Erbium-doped mid-infrared lasers 06. Optical superoscillation without side waves 07. Optical tweezer technology tweaked to overcome dangers of heat 08. The world’s thinnest technology—only two atoms thick 09. Classic magic trick may enable quantum computing 10. Researchers discover unique ‘spider web’ mechanism that traps, kills viruses And others… Growing ‘metallic wood’ to new heights NSF-funded study will examine […]
Backscatter breakthrough runs near-zero-power IoT communicators at 5G speeds everywhere
Science Daily June 25, 2021 Backscatter radio is typically limited to data rates of hundreds of megabits per second because of the low frequency bands used and the modulation techniques involved. An international team of researchers (USA – industry, Georgia Institute of Technology, UK) designed and demonstrated a millimetre-wave modulator and antenna array for backscatter communications at gigabit data rates. It consists of a microstrip patch antenna array and a single pseudomorphic high-electron-mobility transistor that supports a range of modulation formats including binary phase shift keying, quadrature phase shift keying and quadrature amplitude modulation. The circuit is additively manufactured with […]
Classic magic trick may enable quantum computing
Phys.org June 22, 2021 In a proof of principle experiment researchers at the DOE’s Thomas Jefferson National Accelerator Facility are preparing to trap and levitate particles inside a cavity using an electric field. Intrinsic characteristics of superconducting radiofrequency (SRF) cavities will overcome some limits of laser trapping. If they can levitate a particle, they might be able to impart a quantum state on it by cooling the trapped particle to its lowest possible energy level. A levitated particle in an SRF cavity that is under vacuum and chilled to super cold temperatures will only interact with the cavity’s electric field […]
A crystal made of electrons
Phys.org July 1, 2021 An international team of researchers (Switzerland, USA – Harvard University, Germany, Japan) has succeeded in observing Wigner crystals which consist of only electrons predicted almost ninety years ago. The team used optical spectroscopy to demonstrate that electrons in a monolayer semiconductor with density lower than 3 × 1011 per centimetre squared. The combination of a high electron effective mass and reduced dielectric screening enabled them to observe electronic charge order even in the absence of a moiré potential or an external magnetic field. The findings demonstrate that charge-tunable transition metal dichalcogenide monolayers enable the investigation of […]
‘Edge of chaos’ opens pathway to artificial intelligence discoveries
Phys.org June 29, 2021 An international team of researchers (Australia, Japan) discovered that on the neuromorphic dynamics of nanowire networks (NWNs), a unique brain-inspired system with synapse-like memristive junctions embedded within a recurrent neural network-like structure. Through simulation and experiment they elucidated how collective memristive switching gives rise to long-range transport pathways, drastically altering the network’s global state via a discontinuous phase transition. The spatio-temporal properties of switching dynamics are found to be consistent with avalanches displaying power-law size and life-time distributions, with exponents obeying the crackling noise relationship, thus satisfying criteria for criticality, as observed in cortical neuronal cultures. […]