Phys.org June 13, 2024 Checkerboard lattices—where the resulting structure is open, porous, and highly symmetric—are difficult to create by self-assembly. Synthetic systems that adopt such structures typically rely on shape complementarity and site-specific chemical interactions that are only available to biomolecular systems (e.g., protein, DNA). A team of researchers in the US (University of California at San Diego, Duke University) demonstrated the assembly of checkerboard lattices from colloidal nanocrystals that harnessed the effects of multiple, coupled physical forces at disparate length scales and that did not rely on chemical binding. Colloidal Ag nanocubes were bi-functionalized with mixtures of hydrophilic and […]
New fabric makes urban heat islands more bearable
Science Daily June 13, 2024 Urban areas have heat island effects that largely diminish the effectiveness of cooling textiles as wearable fabrics because they absorb emitted radiation from the ground and nearby buildings. A team of researchers in the US (University of Chicago, Duke University) developed a mid-infrared spectrally selective hierarchical fabric (SSHF) with emissivity greatly dominant in the atmospheric transmission window through molecular design, minimizing the net heat gain from the surroundings. The SSHF featured a high solar spectrum reflectivity of 0.97 owing to strong Mie scattering from the nano-micro hybrid fibrous structure. The SSHF was 2.3°C cooler than […]
Physicists discover a new optical property that measures the twist in tiny helicesÂ
Phys.org June 17, 2024 Biomimetic nanotechnology and self-assembly advances need chirality. There is a need to develop general methods to characterize chiral building blocks at the nanoscale in liquids such as water. An international team of researchers (UK, Italy, USA – University of Nebraska, Pennsylvania State University) observed chiroptical second-harmonic Tyndall scattering effect in high-refractive-index dielectric nanomaterial Si nanohelices. They provided a theoretical analysis that explained the origin of the effect and its direction dependence, resulting from different specific contributions of “electric dipole–magnetic dipole” and “electric dipole–electric quadrupole” coupling tensors. They narrowed down the number of such terms to 8 […]
Quantum computing trade-off problem addressed by new system
Phys.org June 18, 2024 The lack of nonlinearity in photonics has led to encoded measurement-based quantum computing, which relies on linear operations but requires access to resourceful (’nonlinear’) quantum states. In contrast, superconducting microwave circuits offer engineerable nonlinearities but suffer from static Kerr nonlinearity. An international team of researchers (Sweden, Germany) demonstrated universal control of a bosonic mode composed of a superconducting nonlinear asymmetric inductive element (SNAIL) resonator, enabled by native nonlinearities in the SNAIL element. They suppressed static nonlinearities and dynamically activated nonlinearities up to third order by fast flux pulses. They experimentally realized a universal set of generalized […]
Quantum data assimilation: A quantum leap in weather prediction
Science Daily June 13, 2024 In the context of numerical weather prediction (NWP), data assimilation is particularly vital for improving initial conditions and subsequent predictions. However, the computational demands imposed by conventional approaches, pose notable challenges in computational time. Researchers in Japan proposed quantum data assimilation approach which solves the data assimilation problem using quantum annealers. Their experiments using the 40-variable Lorenz model were highly promising, showing that the quantum annealers produced an analysis with comparable accuracy to conventional data assimilation approaches. In particular, the D-Wave Systems physical quantum annealing machine achieved a significant reduction in execution time… read more. […]
Quantum entangled photons react to Earth’s spin
Phys.org June 14, 2024 Optical quantum interferometers are of particular interest because of mature methods for generating and manipulating quantum states of light. Their increased sensitivity promises to enable tests of quantum phenomena. However, this requires long and decoherence-free processing of quantum entanglement, which, for large interferometric areas, remains unexplored territory. Researchers in Austria developed a table-top experiment using maximally path-entangled quantum states of light in a large-scale interferometer sensitive enough to measure the rotation rate of Earth with high sensitivity. According to the researchers further improvements to their methodology will enable tests for fundamental physics allowing the exploration of […]
Researchers leverage shadows to model 3D scenes, including objects blocked from view
Phys.org June 18, 2024 Existing methods for single-view 3D reconstruction with Neural radiance fields (NeRF) rely on either data prior to hallucinate views of occluded regions which may not be physically accurate, or shadows observed by RGB cameras which are difficult to detect in ambient light and low albedo backgrounds. A team of researchers in the US (MIT, industry) proposed using time-of-flight data captured by a single-photon avalanche diode to overcome these limitations models two-bounce optical paths with NeRF using lidar transient data for supervision. By leveraging the advantages of both NeRF and two-bounce light measured by lidar they reconstructed […]
Scientists suggest causes behind one of the most significant climate catastrophes
Phys.org June 17, 2024 Anoxic events are prolonged periods where large expanses of the Earth’s oceans are depleted of dissolved oxygen, which creates toxic waters and leads to mass extinction and habitat loss. The cause of this anoxic event which lasted >500,000 years has been a source of debate among experts. Researchers in the UK used basin sedimentary mercury (Hg) concentrations to determine the timing of volcanism, and neodymium (Nd) and strontium (Sr) isotopes for sedimentary provenance. High Hg concentrations compared to Northern Hemisphere records, and a shift to radiogenic Nd isotopes, indicated Kerguelen LIP volcanic activity and plateau uplift […]
Top 10 Science and Technology Inventions for the Week of June 14, 2024
01. New method optimizes lithium extraction from seawater and groundwater 02. Pseudomagic quantum states: A path to quantum supremacy 03. ‘Quantum optical antennas’ provide more powerful measurements on the atomic level 04. Researchers demonstrate new way to ‘squeeze’ infrared light 05. New theory describes how waves carry information from surroundings 06. Scientists create world’s strongest iron-based superconducting magnet using AI 07. Scientists develop fatigue-free ferroelectric material 08. How tiny cracks lead to large-scale faults 09. A ‘liquid battery’ advance—strategies for electrocatalytic hydrogenation 10. Study confirms the rotation of Earth’s inner core has slowed And others Earth and space share the […]
Earth and space share the same turbulence
Phys.org June 7, 2024 The dynamics of upper atmosphere winds differ significantly from those at lower altitudes, with larger magnitudes and increased sensitivity to solar events. An international team of researchers (Germany, Japan) used multi-year observations of cross-track winds (u) from the CHAllenging Minisatellite Payload (CHAMP) and the Gravity Field and Steady State Ocean Circulation Explorer (GOCE) to calculate third-order structure functions in the thermosphere as a function of horizontal separation (s). They presented two main characteristics – they are consistently positive, predicting a preferential cyclonic rotational motion (counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere) and, […]