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Loading quantum information deterministically onto a quantum node is an important step toward a quantum network. Here, we demonstrate that coherent-state microwave photons with an optimal temporal waveform can be efficiently loaded onto a single superconducting artificial atom in a semi-infinite one-dimensional (1D) transmission-line waveguide. Using a weak coherent state (the number of photons (

A detailed investigation of choline chloride-lactic acid (ChCl-LA)-based deep eutectic solvent (DES) extraction of lignin nanoparticles from herbaceous biomass (wheat straw) was conducted. It was f...

In this study, we reported a method to prepare a lignin based cryogel by cross-linking deep eutectic solvent (DES) extracted lignin and formaldehyde as an alternative to replace resorcinol-formaldehyde (RF) based aerogel. The resulting lignin-formaldehyde cryogel has a highly porous structure (172.8 m2/g surface area) with a high dimension stability. We found that the hydroxyl group and carbonyl group of DES lignin provide reactive sites to cross-link with formaldehyde through electrophilic addition and aldol condensation reaction. We also found that using choline chloride-lactic acid (ChCl-Lac) DES as a solvent during the lignin-formaldehyde cryogel formation is critical to prevent the shrinkage of the final cyrogel. The ensuing lignin-formaldehyde cryogel has promising properties such as high thermostability, low thermal conductivity, and good fire retardancy.

Probing spatial variation of temperature at the nanoscale provides key information for exploring diverse areas of modern science and technology. Despite significant progress in the development of contact thermometers with high spatial resolution, one inherent disadvantage is that the quantitative analysis of temperature can be complicated by the direct thermal contact. On the other hand, noncontact infrared radiation thermometer is free from such contact-induced disturbance, but suffers from insufficient spatial resolution stemming from diffraction-limit in the micrometer range. Combining a home-built sensitive infrared microscope with a noncontact scattering probe, we detected fluctuating electromagnetic evanescent fields on locally heated material surface, and thereby mapped temperature distribution in subwavelength scales. We visualize nanoscale Joule heating on current-carrying metal wires and find localized "hot-spots" developing along sharp corners of bended wires in the temperature mapping. Simulation calculations give quantitative account of the nanoscale temperature distribution, definitely indicating that the observed effect is caused by the nonuniform energy dissipation due to the current-crowding effect. The equipment in this work is a near-field version of infrared radiation thermometer with a spatial resolution far below the detection wavelength (100 nm, or λ/140) in which local temperature distribution of operating nanoscale devices can be noninvasively mapped with a temperature resolution ∼2 K at room-temperature.

Hierarchical structures are commonly observed in nature and possess unique properties. The fabrication of hierarchical structures with well-controlled sizes in different length scales, however, is still a great challenge. To further understand the morphologies and properties of the hierarchical structures, here we present a novel strategy to prepare hierarchical polymer structures by combining the modified breath figure method and the template method. Poly(methyl methacrylate) (PMMA) honeycomb films with regular micropores are first prepared using the modified breath figure method by dipping PMMA films into mixtures of chloroform and methanol. The polymer chains on the honeycomb films are then annealed and wetted into the nanopores of anodic aluminum oxide templates via capillary forces, resulting in the formation of hierarchical polymer structures. The morphologies of the polymer structures, which can be controlled by the molecular weights of the polymers and the concentrations of the polymer solutions, are characterized by scanning electron microscopy. The surface wettabilities of the polymer structures are also examined by water contact angle measurements, and the hierarchical structures are observed to be more hydrophobic than the flat films and honeycomb films. This work not only provides a feasible approach to fabricate hierarchical polymer structures with controlled sizes but also gives a better understanding of the relationship between surface morphologies and properties.