01. Nano-architected material refracts light backward – an important step toward one day creating photonic circuits 02. A nanoscale 3D structure to control light 03. A new amplifying technique for weak and noisy optical signals 04. New approach transports trapped ions to create entangling gates 05. A new method for quantum computing 06. New power transfer technology provides unprecedented freedom for wireless charging 07. Physicists manipulate magnetism with light 08. Scientists develop insect-sized flying robots with flapping wings 09. Scientists weave atomically thin wires into ribbons 10. Tiny materials lead to a big advance in quantum computing And others… Bacteria […]
Bacteria Communicate Using Chemical Signals Comparable to Radio Waves
SciTech Daily January 31, 2022 Researchers at UCLA elucidated how bacteria communicate about the existence of a surface using a messenger molecule called cyclic diguanylate (c-di-GMP) signals which are analogous to, AM radio and FM radio which encodes signals by the number of oscillations in the wave over a given period. The signal acts like a knob. They identified three important factors that control the formation of biofilm: average levels of c-di-GMP, the frequency of oscillations in c-di-GMP levels, and the degree of cell movement on the surface where the biofilm is forming. According to the existing paradigm one input […]
Chinese and U.S. University Rankings
Center for Security and Emerging Technology January 28, 2022 In a CSET Report researchers at Georgetown University assess the quality of universities in China and the United States based on their performance in two well-regarded rankings of global universities. They found Chinese universities have steadily moved up the rankings over time, driven largely by increases in research productivity and a series of state-sponsored higher education initiatives. Between 2010 and 2020, the number of U.S. universities that appeared in the top 500 on at least one global ranking dropped from 160 to 137, while the number that appeared on both rankings […]
Engineering a multi-element atomic arrangement
Phys.org February 1, 2022 Nano-multi-principal element intermetallic (MPEI) compounds composed of multi-elemental metals in definite proportions have properties and crystal structure that are different from its constituents. An international team of researchers (USA – University of Maryland, Brookhaven National Laboratory, University of Delaware, Oak Ridge National Laboratory, Argonne National Laboratory, Washington State University, UC San Diego, Canada) has demonstrated a disorder-to-order phase transition approach that enabled the synthesis of ultrasmall and stable MPEI nanoparticles (up to eight elements). They applied 5 min of Joule heating to promote the phase transition of the nanoparticles into L10 intermetallic structure, which is then […]
Nano-architected material refracts light backward – an important step toward one day creating photonic circuits
Nanowerk January 28, 2022 Negative refraction has not been observed in nature but was theorized to occur in artificially periodic materials. Researchers at Caltech designed, fabricated 3D photonic crystals (PhCs) capable of negative refraction in the mid-infrared. Band structure and equifrequency contours were calculated to inform the design of 3D polymer–germanium core–shell PhCs. They successfully characterized a polymer–Ge core–shell lattice and mapped its band structure, which were used to calculate the PhC refraction behavior. An analysis of wave propagation revealed that this 3D core–shell PhC refracts light negatively and possesses an effective negative index of refraction in the experimentally observed […]
A nanoscale 3D structure to control light
Phys.org February 2, 2022 Metamaterials can be engineered to produce desired interactions with light or sound waves. However, functionality of the devices can be limited by the corresponding design space. A team of researchers in the US (Pennsylvania State University, Sandia National Laboratory) leveraged a combination of a genetic algorithm (GA) based optimization method and a membrane projection lithography (MPL) fabrication approach, to demonstrate a quasi-3D metamaterial for broadband asymmetric transmission (AT) of linearly polarized mid-infrared light. An efficient exploration of 3D plasmonic meta-atoms with broken mirror symmetry in the light propagation direction allows the satisfaction of the rigorous conditions […]
A new amplifying technique for weak and noisy optical signals
Phys.org February 2, 2022 Mitigating the stochastic noise introduced during the generation, transmission, and detection of temporal optical waveforms remains a significant challenge across many applications. An international team of researchers (Canada, Spain) proposed a versatile concept for simultaneous amplification and noise mitigation of temporal waveforms, and successfully demonstrated on optical signals with bandwidths spanning several orders of magnitude, from the kHz to GHz scale. The concept was based on lossless temporal sampling of the incoming coherent waveform through Talbot processing. By reaching high gain factors (>100), they showed the recovery of ultra-weak optical signals, with power levels below the […]
New approach transports trapped ions to create entangling gates
Phys.org January 28, 2022 Trapped ions excited with a laser beam can be used to create entangled qubits in quantum information systems but addressing several stationary pairs of ions in a trap requires multiple optical switches and complex controls. Researchers at Georgia Tech Research Institute moved calcium ions held in a surface electrode trap through a stationary bichromatic optical beam potentially integrating the existing transport control into quantum logic operations. Measurements showed that the entangled quantum state of the two qubits transported through the optical beam had a fidelity comparable to entangled states produced by stationary gates performed in the […]
A new method for quantum computing
Phys.org January 31, 2022 Using trapped-ion platform and optical tweezers researchers in the Netherlands have constructed new building blocks for quantum computing that pose fewer technical difficulties than current state-of-the art methods. Since the electric field allows for long-range qubit-qubit interactions mediated by the center-of-mass motion of the ion crystal alone, it is inherently scalable to large ion crystals. The proposed scheme does not rely on ground-state cooling. They studied the effects of imperfect cooling of the ion crystal, as well as the role of unwanted qubit-motion entanglement, and discuss the prospects of implementing the state-dependent tweezers in the laboratory… […]
New power transfer technology provides unprecedented freedom for wireless charging
Science Daily February 1, 2022 Using electromagnetics researchers in Finland have developed a free-positioning wireless power transfer technology that can direct power to individual devices without needing plugs, tracking devices , or complex computing. Devices can be charged while they are moving. Multiple transmitters (Txs) are placed in a pad-like area, and the transmitter coils are optimally excited to enable robust and efficient power transfer to movable receivers within the charging area. The configuration enables almost continuous magnetic flux path from a set of Tx coil(s) to another set of Tx coil(s) through the receiver coil ferrite core ensuring efficient […]