Generation and Detection of a Directed Monoenergetic Neutrino Beam with Hydrogen-Like Ions

We consider two possible schemes for generation and detection of a monoenergetic directed beam of neutrinos which may have application to neutrino communication. First, we consider generation of a directed neutrino beam using electron capture beta decay in hydrogen-like ions. Next, we suggest detection of a directed neutrino beam using resonant absorption of a neutrino by a bare nucleus with the generation of a bound electron. This reaction is inverse to electron capture beta decay, and we call it “Bound State Inverse Beta Decay (BSIBD)”. We show that the recoil effect can be eliminated by an appropriate choice of velocities for the ions and bare nuclei. Finally, we consider a combination of a solid state source of a directed mono-energetic neutrino beam and its detection using BSIBD.

Directional neighbor discovery in mmWave wireless networks

The directional neighbor discovery problem,i.e,spatial rendezvous,is a fundamental problem in millimeter wave(mmWave)wireless networks,where directional transmissions are used to overcome the high attenuation.The challenge is how to let the transmitter and the receiver beams meet in space under deafness caused by directional transmission and reception,where no control channel,prior information,and coordination are available.In this paper,we present a Hunting based Directional Neighbor Discovery(HDND)scheme for ad hoc mmWave networks,where a node follows a unique sequence to determine its transmission or reception mode,and continuously r0-tates its directional beam to scan the neighborhood for other mmWave nodes.Through a rigorous analysis,we derive the conditions for ensured neighbor discovery,as well as a bound for the worst-case discovery time and the impact of sidelobes.We validate the analysis with extensive simulations and demonstrate the superior perfor-mance of the proposed scheme over several baseline schemes.

Spike-and nucleocapsid-based gold colloid assay toward the development of an adhesive bandage for rapid SARS-CoV-2 immune response detection and screening

Immunoglobulin M(IgM)and immunoglobulin G(IgG)antibodies are important biomarkers used for the diagnosis and screening of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infections in both symptomatic and asymptomatic individuals.These antibodies are highly specific to the spike(S)and nucleocapsid(N)proteins of the SARS-CoV-2 virus.This paper outlines the development steps of a novel hybrid(vertical-lateral-vertical)flow assay in the form of a finger-stick point-of-care device,similar to an adhesive bandage,designed for the timely detection and screening of IgM and IgG immune responses to SARS-CoV-2 infections.The assay,comprising a vertically stacked plasma/serum separation membrane,conjugate pad,and detection(readout)zone,utilizes gold nanoparticles(AuNPs)conjugated with SARS-CoV-2 S and N proteins to effectively capture IgM and IgG antibodies from a pinprick(~15µL)of blood in just one step and provides results of no immune IgM−/IgG−,early immune IgM+/IgG−,active immune IgM+/IgG+or immune IgM−/IgG+in a short amount of time(minutes).The adhesive bandage-like construction is an example of the design of rapid,low-cost,disposable,and easy-to-use tests for large-scale detection and screening in households.Furthermore,the bandage can be easily adjusted and optimized to detect different viral infections as they arise by simply selecting appropriate antigens related to pandemics and outbreaks.

Electro-optic tuning in composite silicon photonics based on ferroionic 2D materials

Tunable optical materials are indispensable elements in modern optoelectronics,especially in integrated photonics circuits where precise control over the effective refractive index is essential for diverse applications.Two-dimensional materials like transition metal dichalcogenides(TMDs)and graphene exhibit remarkable optical responses to external stimuli.However,achieving distinctive modulation across short-wave infrared(SWIR)regions while enabling precise phase control at low signal loss within a compact footprint remains an ongoing challenge.In this work,we unveil the robust electro-refractive response of multilayer ferroionic two-dimensional CuCrP2S6(CCPS)in the near-infrared wavelength range.By integrating CCPS into silicon photonics(SiPh)microring resonators(MRR),we enhance lightmatter interaction and measurement sensitivity to minute phase and absorption variations.Results show that electrically driven Cu ions can tune the effective refractive index on the order of 2.8×10−3 RIU(refractive index unit)while preserving extinction ratios and resonance linewidth.Notably,these devices exhibit low optical losses and excellent modulation efficiency of 0.25 V.cm with a consistent blue shift in the resonance wavelengths among all devices for either polarity of the applied voltage.These results outperform earlier findings on phase shifters based on TMDs.Furthermore,our study demonstrates distinct variations in electro-optic tuning sensitivity when comparing transverse electric(TE)and transverse magnetic(TM)modes,revealing a polarization-dependent response that paves the way for diverse applications in light manipulation.The combined optoelectronic and ionotronic capabilities of two-terminal CCPS devices present extensive opportunities across several domains.Their potential applications range from phased arrays and optical switching to their use in environmental sensing and metrology,optical imaging systems,and neuromorphic systems in light-sensitive artificial synapses.