Hexagonal Boron Nitride: understanding and tailoring its unique electronic and phononic properties
Résumé
Hexagonal boron nitride (hBN) is a key compound in the field of 2D materials research. It has been shown to have unique physical properties that make it suitable for a wide range of applications, from quantum technologies to thermal management applications and deep UV optoelectronics[1, 2]. It exhibits strong thickness-dependent second order non-linearities. By modifying its defects, it can become a single-photon emitter at room temperature and, finally, even indirectly, its wide band gap provides a very high internal quantum efficiency for deep UV emitters and detectors. All these features derive from its highly anisotropic crystal structure and polar chemical bonding, which result in a peculiar electronic band structure, phonon dispersion, strong electron-phonon coupling and huge excitonic effects. Starting from the description of its constituent elements, I will describe the reasons for its unique properties and highlight recent discoveries, from thermal-radiative to optical response, from the monolayer to the bulk limit, suggesting then possible ways to further exploit its enormous potential[3, 4, 5, 6, 7].