Shot noise-mitigated secondary electron imaging with ion count-aided microscopy.

Modern science is dependent on imaging on the nanoscale, often achieved through processes that detect secondary electrons created by a highly focused incident charged particle beam. Multiple types of measurement noise limit the ultimate trade-off between the image quality and the incident particle dose, which can preclude useful imaging of dose-sensitive samples. Existing methods to improve image quality do not fundamentally mitigate the noise sources.

Shot noise-mitigated secondary electron imaging with ion count-aided microscopy.

Modern science is dependent on imaging on the nanoscale, often achieved through processes that detect secondary electrons created by a highly focused incident charged particle beam. Multiple types of measurement noise limit the ultimate trade-off between the image quality and the incident particle dose, which can preclude useful imaging of dose-sensitive samples. Existing methods to improve image quality do not fundamentally mitigate the noise sources.

Intrinsic (Trap-Free) Transistors Based on Epitaxial Single-Crystal Perovskites.

The first experimental realization of the intrinsic (not dominated by defects) charge conduction regime in lead-halide perovskite field-effect transistors (FETs) is reported. The advance is enabled by: i) a new vapor-phase epitaxy technique that results in large-area single-crystalline cesium lead bromide (CsPbBr ) films with excellent structural and surface properties, including atomically flat surface morphology, essentially free from defects and traps at the level relevant to device operation; ii) an extensive materials analysis of these films using a variety of thin-film and surface probes certifying the chemical and structural quality of the material; and iii) the fabrication of nearly ideal (trap-free) FETs with characteristics superior to any reported to date. These devices allow the investigation of the intrinsic FET and (gated) Hall-effect carrier mobilities as functions of temperature.

An intra-cytoplasmic route for SARS-CoV-2 transmission unveiled by Helium-ion microscopy.

SARS-CoV-2 virions enter the host cells by docking their spike glycoproteins to the membrane-bound Angiotensin Converting Enzyme 2. After intracellular assembly, the newly formed virions are released from the infected cells to propagate the infection, using the extra-cytoplasmic ACE2 docking mechanism. However, the molecular events underpinning SARS-CoV-2 transmission between host cells are not fully understood.

Nature of the metal-insulator transition in few-unit-cell-thick LaNiO films.

The nature of the metal-insulator transition in thin films and superlattices of LaNiO only a few unit cells in thickness remains elusive despite tremendous effort. Quantum confinement and epitaxial strain have been evoked as the mechanisms, although other factors such as growth-induced disorder, cation non-stoichiometry, oxygen vacancies, and substrate-film interface quality may also affect the observable properties of ultrathin films. Here we report results obtained for near-ideal LaNiO films with different thicknesses and terminations grown by atomic layer-by-layer laser molecular beam epitaxy on LaAlO substrates.