Determination of Quasi-single Particle Bandgap by Using the Combination of Photoelectron and Inverse-photoelectron Spectroscopy

The observation of many previously unseen physical phenomena, especially in the nano-size world, has been the most dramatically advanced field of study due to the advancement of analytical technology. In particular, cutting-edge analytical methods based on X-rays and electrons have enabled the visualization of atomic-level images and structures. Currently, these methods are widely utilized not only in the field of physics but also in various engineering disciplines, such as electronics, energy, bio-medicine and hydrogen storage. Korea Institute of Science and Technology (KIST), established in 1966, is the first government-funded general research institute in South Korea that contributes to the technological development in key national sectors. Advanced analysis and data center at KIST have played a crucial role in the advancement of national science and technology by providing essential analysis and new analytical technologies. In this special issue, we will discuss advanced analytical equipment available at KIST covering the entire spectrum of analytical technology from fundamental principles to applications and utilization. Specifically, we will focus on the representative analytical technique for physics research, such as photoelectron spectroscopy (PES), X-ray diffraction (XRD), transmission electron microscopy (TEM), and machine learning-based analytical methods for their interpretation.