Nearly 40 years after the discovery of high-temperature superconductivity (HTS), a large-scale application is in sight: the so-called compact fusion using REBa2Cu3Ox (REBCO, RE: Rare Earth) HTS wire. The key technology is the development of a large and high-field HTS magnet that has never existed before. REBCO wire used will reach several hundred million kilometers in total. Here, the technical road to mass production of REBCO wire (mainly made by Ion Beam Assisted Deposition (IBAD)- Pulsed Laser Deposition (PLD) method) is reviewed. Also challenges and prospects for compact fusion application are briefly described. In particular, various technologies for the REBCO wire industrialization will be of great help for young researchers.

Graphene is a carbon-based atomically thin two-dimensional material that exhibits various excellent optical and electronic properties that cannot be demonstrated by conventional bulk materials. In particular, the broadband photodetection ability, high carrier mobility, and low environmental impact of graphene are advantageous for infrared (IR) sensor applications. In this article, the expectations and challenges for graphene-based optical sensor applications are clarified and the photodetection mechanism for graphene-based optical sensors is explained. Photogating, which was introduced as a promising method for enhancing sensor responsivity, is then discussed. Finally, both individual graphene photogated diodes (GPDs), which exhibit a high responsivity and low dark current, and graphene-based IR image sensors fabricated from a large array of such GPDs, are reviewed.

The nucleation process in the initial stage of a phase change is a fundamental process related to various fields, but it is known that the theoretically predicted nucleation rate is highly indeterminate. We performed direct, large-scale molecular dynamics (MD) simulations of homogeneous nucleation processes such as vapor-to-liquid nucleation and liquid-to-vapor nucleation. MD simulations are a powerful method to investigate the details of the nucleation process at the molecular level, and provide not only the nucleation rate but also critical nuclei, Gibbs free energy for nucleation, sticking probabilities, and other information to verify the theory from various aspects. By using systems with a large number of particles, such as nucleation from the gas phase using 8 billion Lennard-Jones molecules or 4 million water molecules, and bubble nucleation from the liquid phase with 500 million Lennard-Jones molecules, it has become possible to reproduce low nucleation rates under the same conditions as experimental data and to construct nucleation models with high accuracy.

Optical observation of ultrathin films on substrates is important in layered materials research. Ultrathin films have been visualized using the optical interference effect of thermally-grown silicon substrates. We propose a visualization technique that focuses on the optical properties of the substrate. The method allows recognition of monolayer and reliable identification of the number of layers of hexagonal boron nitride films. Furthermore, the monolayer thickness difference in a thick film is visualized, which can be applied to the selection of mechanically exfoliated films.

Most electrolytes increase the surface tension of water. According to thermodynamics, this leads to a repulsive force between the gas-liquid interface and the ions. We first introduce the thermodynamic properties of such surface tension and the computational theory of surface tension. Next, a quantitative comparison of ion adsorption for individual ion species is presented based on theoretical analysis of experimental data. The analysis of experimental data on surface tension and contact angle at the oil-water interface and hydrophobic solid-liquid interface also reveals the universal nature of the interaction between ions and hydrophobic interfaces.

We recently feel that researchers are not only expected to submit papers, but also to apply patents. Meanwhile, except for some researchers, applying a patent is a hurdle, and it seems that few researchers are actively motivated to file applications. This paper is intended for researchers who are inexperienced in patent application, but it is also intended to be helpful for researchers who wish to review patent applications. We particularly have focused on the importance of patents, the concept of patentability, deciding whether or not to apply a patent, the data necessary for filing an application, how to search for patents, the timing of patent consultations and applications, and how to proceed with applying a patent.