All-dry pick-up and transfer method for quantum emitter arrays in hexagonal boron nitride

Single photon emitters in hexagonal boron nitride are based on fluorescent point-like defects. These defects possess exceptional photophysical properties and have been the focus of research for their potential to advance photonic quantum technologies. However, achieving scalable integration of these emitters onto arbitrary platforms with high yield while retaining their characteristics remains challenging when the substrate is incompatible with the fabrication method. In this work, we introduce an all-dry transfer method that addresses these challenges more effectively than existing techniques. This polymer stamp-assisted transfer maintains high output and preserves emitter characteristics while eliminating wet chemical processes. Comprehensive post-transfer characterization verified retention of the defining single-photon characteristic, the second-order correlation function g(2)(0), and revealed an improvement of about 46%. This enhancement in photon purity may result from thermal desorption of weak surface contaminants during mild heating and from changes in local stress and strain induced by the transfer process. While g(2)(0) showed substantial improvement, other photophysical properties, such as emitter lifetime, emission spectrum, and photostability, remained nearly unchanged, indicating that the transfer preserves the overall optical quality. The technique achieves emitter survival probability of 81.8%, where success requires both the structural integrity of the transferred flake and the survival of the emitters with their defining optical properties. This high survival probability demonstrates the potential to scale the integration of single photon emitters across diverse photonic platforms. We expect that this process will contribute to applications of boron nitride defects in quantum technologies.