Atomically thin quantum sensors

Atomically thin two-dimensional materials, with their ultra-thin structure and exceptional sensitivity to the local environment, are emerging as an important platform for next-generation quantum sensing. Their van der Waals bonding and atomic thin layers allow sensing elements to be placed in extremely close proximity to target systems—often just a few atoms away. This proximity dramatically enhances interactions with local optical, mechanical, and electrostatic fields, enabling exceptionally sensitive detection with ultrahigh spatial resolution. Beyond sensitivity, the layered van der Waals architecture offers a unique opportunity to integrate multiple sensing functions into a unified platform, where sensing, signal amplification, and readout can be distributed across tailored layers rather than relying on a single sensor element. Recent advances in optically addressable spin defects in hexagonal boron nitride and excitonic and polaritonic platforms in transition-metal dichalcogenides highlight the emergence of a new generation of quantum and quantum-enhanced sensors. These sensors conform to various substrates and enable multiparameter detection. In this Perspective, we outline the principles that distinguish atomically thin quantum sensors from bulk counterparts and explore emerging opportunities and challenges in developing scalable, multifunctional 2D quantum sensing technologies.