Tailoring polarization in WSe quantum emitters through deterministic strain engineering.

Quantum emitters in transition metal dichalcogenides (TMDs) have recently emerged as a promising platform for generating single photons for optical quantum information processing. In this work, we present an approach for deterministically controlling the polarization of fabricated quantum emitters in a tungsten diselenide (WSe) monolayer. We employ novel nanopillar geometries with long and sharp tips to induce a controlled directional strain in the monolayer, and we report on fabricated WSe emitters producing single photons with a high degree of polarization (99 ± 4%) and high purity ( (0) = 0.

Prevalence, characteristics, and virologic correlations of hepatitis delta (D) among patients with hepatitis B surface antigen in Mongolia.

Clinical and biochemical features of hepatitis delta virus (HDV) infections in Mongolia remain largely unknown. We aimed to investigate the clinical characteristics of HDV patients in Mongolia using several markers. The 143 hepatitis B surface antigen (HBsAg)-positive patients were divided into 122 HDV-positive and 21 HDV-negative patients by HDV RNA positivity.

Probing optical anapoles with fast electron beams.

Optical anapoles are intriguing charge-current distributions characterized by a strong suppression of electromagnetic radiation. They originate from the destructive interference of the radiation produced by electric and toroidal multipoles. Although anapoles in dielectric structures have been probed and mapped with a combination of near- and far-field optical techniques, their excitation using fast electron beams has not been explored so far.

Optical Constants of Several Multilayer Transition Metal Dichalcogenides Measured by Spectroscopic Ellipsometry in the 300-1700 nm Range: High Index, Anisotropy, and Hyperbolicity.

Transition metal dichalcogenides (TMDs) attract significant attention due to their remarkable optical and excitonic properties. It was understood already in the 1960s and recently rediscovered that many TMDs possess a high refractive index and optical anisotropy, which make them attractive for nanophotonic applications. However, accurate analysis and predictions of nanooptical phenomena require knowledge of dielectric constants along both in- and out-of-plane directions and over a broad spectral range, information that is often inaccessible or incomplete.

Tunable self-assembled Casimir microcavities and polaritons.

Spontaneous formation of ordered structures-self-assembly-is ubiquitous in nature and observed on different length scales, ranging from atomic and molecular systems to micrometre-scale objects and living matter. Self-ordering in molecular and biological systems typically involves short-range hydrophobic and van der Waals interactions. Here we introduce an approach to micrometre-scale self-assembly based on the joint action of attractive Casimir and repulsive electrostatic forces arising between charged metallic nanoflakes in an aqueous solution.