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Abstract The challenge of fabricating transparent and conductive (T/C) films and patterns for applications in flexible electronics, touch screens, solar cells, and smart windows remains largely unsolved. Traditional fabrication techniques are complex, costly, time‐consuming, and struggle to achieve the necessary precision and accuracy over electronic and optical properties. Here, hypersurface photolithography (HP), which integrates microfluidics, a digital micromirror device, and photochemical surface‐initiated polymerizations is used to create polymer brush patterns. The high‐throughput optimization enabled by HP provides conditions to fabricate patterns composed of cross‐linked polymer brushes containing Au‐binding 2‐vinylpyrrolidine (2VP) groups with precise control over the height and the composition at each pixel. Au nanoparticles (AuNPs) are incorporated into the polymer brush patterns through in situ reduction of Au ions, resulting in T/C composite AuNP/polymer brush patterns. The sheet resistance at 100 mA of a 2VP‐AuNP‐functionalized patterns on a glass substrate is 0.42 Ω sq⁻¹with 86% transmittance of visible light. Additional patterns demonstrate multiplexing by copatterning rhodamine B functionalized fluorescent polymer brushes and AuNP/polymer brush conductive domains. This work solves the challenge of creating T/C films by forming metal‐polymer composites from polymer brush patterns, offering a scalable solution for electronic and optical device development and fabrication. 

Abstract The potential energy landscape (PEL) formalism is a powerful tool within statistical mechanics to study the thermodynamic properties of classical low-temperature liquids and glasses. Recently, the PEL formalism has been extended to liquids/glasses that obey quantum mechanics, but applications have been limited to atomistic model liquids. In this work, we extend the PEL formalism to liquid/glassy water using path-integral molecular dynamics (PIMD) simulations, where nuclear quantum effects (NQE) are included. Our PIMD simulations, based on the q-TIP4P/F water model, show that the PEL of quantum water is both Gaussian and anharmonic. Importantly, the ring-polymers associated to the O/H atoms in the PIMD simulations, collapse at the local minima of the PEL (inherent structures, IS) for both liquid and glassy states. This allows us to calculate, analytically, the IS vibrational density of states (IS-VDOS) of the ring-polymer system using the IS-VDOS of classical water (obtained from classical MD simulations). The role of NQE on the structural properties of liquid/glassy water at various pressures are discussed in detail. Overall, our results demonstrate that the PEL formalism can effectively describe the behavior of molecular liquids at low temperatures and in the glass states, regardless of whether the liquid/glass obeys classical or quantum mechanics. 

Abstract Establishing connections between material impurities and charge transport properties in emerging electronic and quantum materials, such as wide‐bandgap semiconductors, demands new diagnostic methods tailored to these unique systems. Many such materials host optically‐active defect centers which offer a powerful in situ characterization system, but one that typically relies on the weak spin‐electric field coupling to measure electronic phenomena. In this work, charge‐state sensitive optical microscopy is combined with photoelectric detection of an array of nitrogen‐vacancy (NV) centers to directly image the flow of charge carriers inside a diamond optoelectronic device, in 3D and with temporal resolution. Optical control is used to change the charge state of background impurities inside the diamond on‐demand, resulting in drastically different current flow such as filamentary channels nucleating from specific, defective regions of the device. Conducting channels that control carrier flow, key steps toward optically reconfigurable, wide‐bandgap optoelectronics are then engineered using light. This work might be extended to probe other wide‐bandgap semiconductors (SiC, GaN) relevant to present and emerging electronic and quantum technologies. 

Abstract The silicon vacancy (SiV) center in diamond is drawing much attention due to its optical and spin properties, attractive for quantum information processing and sensing. Comparatively little is known, however, about the dynamics governing SiV charge state interconversion mainly due to challenges associated with generating, stabilizing, and characterizing all possible charge states, particularly at room temperature. Here, multi‐color confocal microscopy and density functional theory are used to examine photo‐induced SiV recombination — from neutral, to single‐, to double‐negatively charged — over a broad spectral window in chemical‐vapor‐deposition (CVD) diamond under ambient conditions. For the SiV⁰to SiV^‐transition, a linear growth of the photo‐recombination rate with laser power at all observed wavelengths is found, a hallmark of single photon dynamics. Laser excitation of SiV^‒, on the other hand, yields only fractional recombination into SiV^2‒, a finding that is interpreted in terms of a photo‐activated electron tunneling process from proximal nitrogen atoms. 

Abstract Amorphous ices are usually classified as belonging to low-density or high-density amorphous ice (LDA and HDA) with densitiesρ_LDA ≈ 0.94 g/cm³andρ_HDA ≈ 1.15−1.17 g/cm³. However, a recent experiment crushing hexagonal ice (ball-milling) produced amedium-density amorphous ice (MDA,ρ_MDA ≈ 1.06 g/cm³) adding complexity to our understanding of amorphous ice and the phase diagram of supercooled water. Motivated by the discovery of MDA, we perform computer simulations where amorphous ices are produced by isobaric cooling and isothermal compression/decompression. Our results show that, depending on the pressure employed, isobaric cooling can generate a continuum of amorphous ices with densities that expand in between those of LDA and HDA (briefly, intermediate amorphous ices, IA). In particular, the IA generated atP ≈ 125 MPa has a remarkably similar density and average structure as MDA, implying that MDA is not unique. Using the potential energy landscape formalism, we provide an intuitive qualitative understanding of the nature of LDA, HDA, and the IA generated at different pressures. In this view, LDA and HDA occupy specific and well-separated regions of the PEL; the IA prepared atP = 125 MPa is located in the intermediate region of the PEL that separates LDA and HDA.