The EHT project has succeeded in imaging a super-massive black hole at the center of the Milky Way Galaxy. This is the second picture of super-massive black holes, following the one taken toward the center of the elliptical galaxy M87. In this article we will provide explanation on the importance of the EHT images, methodology of imaging, and future prospects of the projects.

Orbital angular momentum of light, associated with a helical wavefront, has the capacity of twisting a myriad of materials without chirality to form exotic chiral structures in the materials, manifesting the helical wavefront of the irradiated light field. This exotic interaction between the helical light fields and matters will potentially offer us novel fundamental physical phenomena and advanced photonic technologies to explore new horizon of materials science.

A contact lens display is an ultimate AR display, of which significant issue is the inability of the eyes to focus on the display device embedded in the contact lens as the display screen is too close to the eyes. The holographic contact lens display can address this issue using the holographic technique. This article explains its principle, fundamental experimental results and device techniques required for the commercialization.

This study aims to develop integrated gas sensors for multiple gas sensing. A structure consisting of an ionic gel and multiple electrodes was proposed to realize the integration of gas sensors. Using two of the multiple electrodes, a voltage modulation by gas molecules at the ionic gal/electrode interface was detected by drain current measurement of an externally connected transistor. The voltage modulation depends on the electrode materials and gas molecules. From many kinds of time-series drain current derived from combinations of two electrodes in the multiple electrodes, concentrations of hydrogen, ammonia and ethanol were simultaneously estimated by neural network model.

Inorganic nanoparticles made of inorganic materials are difficult to arrange in an ordered manner and form higher-order structures by themselves. However, surface modification with DNA, which has selective binding properties, as a guiding molecule can control the interaction and binding between nanoparticles to assemble them into desired crystal structures. In this report, the author presents the recent work in finding structural conditions for DNA-modified nanoparticle superlattices that can maintain crystalline symmetry not only in the hydrated state but also after drying, by precisely characterizing crystallinity using small-angle X-ray scattering.

Thanks to the nitrogen-vacancy (NV) center in diamond having excellent spin properties, research on the application of realizing room-temperature quantum devices, such as quantum information devices and quantum sensors, has flourished. While NV spin is usually read out by optical method, the electrical detection of NV spin has attracted attention because its technique is crucial for development and integration of the quantum devices and is well suited to electronics technology. Here we report our studies on the mechanism of electrical detection of NV spins and electrical detection of 14N nuclear spin.

Photoelectron spectroscopy is a method to determine the chemical state of a material by measuring the density of core and valence electronic states of materials. Since the chemical properties of materials in various devices differs significantly between operating and non-operating conditions, it is important to perform “operando measurements”, or measurements made in the operating condition, in order to fully understand devices and materials. In addition, photoemission microspectroscopy is characterized by its ability to analyze the electronic state of a specific area, such as inside a particle or at the materials interface. It is expected that the analysis of practical devices and materials will be greatly advanced by conducting operando photoemission microspectroscopy using cutting-edge synchrotron radiation.