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Abstract Integrated quantum photonics holds significant promise for scalable photonic quantum information processing, quantum repeaters, and quantum networks, but its development is hindered by the mismatch between materials hosting high-quality quantum emitters and those compatible with mature photonic technologies. Heterogeneous integration offers a potential solution to this challenge, yet practical implementations have been limited by inevitable insertion losses at material interfaces. Here, we present a self-aligned heterogeneous quantum photonic integration approach that enables near-unity coupling efficiency at the interface. To showcase our approach, we demonstrate Purcell enhancement of a silicon vacancy (SiV) center in diamond induced by a heterogeneous photonic crystal cavity defined by titanium dioxide (TiO₂), as well as optical spin control and readout via a TiO₂photonic circuit. We further show that, when combined with inverse photonic design, our approach enables efficient and broadband collection of single photons from a color center into a heterogeneous waveguide. Our approach is not restricted to SiV centers or TiO₂; it has the potential to be broadly applied to integrate diverse solid-state quantum emitters with thin-film photonic devices where conformal deposition is possible. Together, these results establish a practical route to scalable quantum photonic integrated circuits that combine high-quality quantum emitters with technologically mature photonic platforms. 

Abstract The development of high‐quality diamond films is pivotal for driving advances in quantum technology, power electronics, and thermal management. The ion implantation and lift‐off technique has emerged as a crucial method for fabricating diamond films with controlled thickness and scalable production of large‐area diamond wafers. This study advances the understanding of critical interface dynamics during diamond epilayer growth on ion‐implanted commercial diamond substrates. Leveraging high‐resolution cross‐sectional electron microscopy and spectroscopic analyses, the direct transformation of the damaged diamond layer is revealed into a graphitic layer during epilayer overgrowth, eliminating the need for high‐temperature annealing. Raman and photoluminescence spectroscopy mappings along the side section highlight the exceptional quality and purity of the epilayer, showcasing nitrogen‐vacancy center densities comparable to electronic‐grade diamond, making it highly suitable for quantum and electronic applications. Finally, the epilayer detaches efficiently via electrochemical etching, leaving a substrate with low surface roughness that is reusable for multiple growth cycles. These results provide valuable insights into refining the ion implantation and lift‐off process, bridging critical gaps in interface evolution, and establishing a foundation for sustainable, high‐performance diamond films across diverse technological applications. 

Abstract Incomplete surgical resection in head and neck cancer can lead to locoregional recurrence in >35% of patients. Approaches such as image‐guided surgery (IGS) and post‐operative photodynamic therapy (PDT) have been proposed to reduce recurrence rates. However, the PDT doses needed to eliminate all unresected diseases are not established. This in vitro proof‐of‐concept study aims to predict head and neck tumor nodule viability in vitro following PDT with TLD1433 using the IGS probe ABY‐029. ABY‐029 is an EGFR‐specific affibody‐IRDye800CW conjugate that has undergone Phase 0 evaluation studies in head and neck cancer, among others. TLD1433 is a ruthenium‐based photosensitizer in a Phase II trial for non‐muscle invasive bladder cancer. Here, we demonstrate that decreases in fluorescence emission of ABY‐029 bound to MOC1 mouse head and neck cancer nodules in vitro can be predictive of TLD1433 PDT responses. Results show that photoactivation of TLD1433 produces reactive oxygen species (ROS) that reduce MOC1 nodule fractional viability in a manner that is inversely correlated with ABY‐029 fluorescence intensity (Pearson'sr = −0.9148,R² = 0.8369,p < 0.0001). We hypothesize that this is due to ROS‐mediated degradation of IRDye800CW. The findings warrant further studies using head and neck cancer nodules with heterogenous PDT responses and EGFR expression levels. If successful, the future goal would be to use ABY‐029 to guide the dosimetry of intraoperative PDT of the surgical bed after IGS to eliminate all microscopic diseases, reduce recurrence rates, and prolong survival. 

Image resolution and field of view in far-field optical microscopy are often inversely proportional to one another due to digital sampling limitations imposed by the magnification of the system and the pixel size of the sensor. We present a method including a spatial shifting mechanism and a reconstruction algorithm that bypasses this trade-off by shifting the sample to be imaged by subpixel increments, before registering the images via phase correlation and combining the resulting registered images using the shift-and-add approach. Importantly, this method requires no specific optical components that are uncommon to commercially available or custom-built microscope systems. The findings of the presented study demonstrate an improvement to spatial resolution of ∼42% while maintaining the system’s field of view (FOV), leading to a more than twofold improvement to the system’s space–bandwidth product (SBP).