Quantum transport phenomena in narrow-gap semiconductors under high pressure and high magnetic field

In this article, we review our exploration of unconventional electronic states near the metal-insulator boundary in black phosphorus and lead telluride, which have long been known as narrow-gap semiconductors with simple crystal structure. In such low carrier systems with high mobility, the energy band structure and physical property can be drastically affected by application of high magnetic field and high pressure. High pressure is a powerful tool to continuously tune the band structure from semiconductor to semimetal without degradation of the mobility.