Researchers from the Laboratory of Nanoscale Biology at the École Polytechnique Fédérale de Lausanne (EPFL), including Eveline Mayner, Yaroslav Zhumagulov, Cristian de Giorgio, Feihong Chu, Prabhu Swain, Georg Fantner, Andras Kis, Oleg Yazyev, and Aleksandra Radenovic, have made a significant advancement in the field of quantum sensing and information technologies. Their work focuses on enhancing the photoluminescence (PL) intensity of spin defects in two-dimensional materials, specifically the negatively charged boron vacancy (VB-) in hexagonal boron nitride (hBN).
The team fabricated a van der Waals heterostructure by combining hBN with a sensitizing donor layer, lead iodide (PbI2). This combination effectively boosted the PL intensity from the VB- by a factor of 5 to 45. The enhancement is attributed to the type-I band alignment at the heterojunction, which facilitates efficient exciton migration while suppressing back-electron transfer. Additionally, the strong spectral overlap between the PbI2 emission and defect absorption supports efficient fluorescence resonance energy transfer. These mechanisms were predicted through ab initio density functional theory (DFT) and confirmed experimentally.
The researchers demonstrated that the heterostructure exhibits enhanced continuous-wave optically detected magnetic resonance (ODMR) sensitivity. This makes it a precise probe for detecting external magnetic fields. The work, published in the journal Nature Communications, establishes a proof-of-concept for amplifying weak defect signals in nanomaterials. This advancement highlights a new strategy for engineering the optical and magnetic responses of these materials, which could have significant implications for the energy sector.
In the energy industry, quantum sensing technologies can be applied to improve the efficiency and reliability of energy systems. For instance, precise magnetic field sensing can enhance the monitoring and control of electrical grids, leading to better management of power distribution and reduced energy losses. Additionally, the ability to engineer the optical and magnetic responses of nanomaterials can pave the way for developing advanced sensors and devices that are crucial for renewable energy technologies, such as solar cells and energy storage systems. This research represents a step forward in harnessing the potential of spin defects in two-dimensional materials for practical applications in the energy sector.
This article is based on research available at arXiv.