Investigation on exciton-phonon optical properties and Raman shift in hexagonal Boron Nitride (hBN) monolayers using Raman spectroscopy and photoluminescence measurement towards non-cryogenic operation

Two-dimensional solid-states systems possess versatile properties that can be exploited for various applications in optoelectronics and quantum communications. Among different two-dimensional systems, hexagonal Boron Nitride monolayers are promising due to their graphene-like crystallinity which can mitigate the interfacial differences between graphene and conventional substrates. Moreover, owing to their large bandgap energy, single-photon emissions have been observed from defect-centers of hexagonal Boron Nitride at room-temperature. Understanding the role of exciton-phonon couplings near the defect-centers is important due to the decoherence mechanism of quantum optical properties and for operation at non-cryogenic temperature. Our work will show various optical properties of hexagonal Boron Nitride monolayers using Raman spectroscopy and Photoluminescence measurements. We show correlations between Raman shifts and the layer thickness and discuss exciton-phonon interactions near single photon emitter defect-sites via temperature dependent Photoluminescence measurement.