Research Track Leaders: Dr. Xinyu Ma and Philipp Lohmann.

We develop broad-spectrum thin-film ferroelectric integrated photonic modulators for qubit control in quantum computing. Our work focuses on thin-film lithium niobate/tantalate (LNOI/LTOI) electro-optic circuits that can provide fast, efficient, and stable control of optical signals across different wavelength ranges. By extending integrated photonic modulation from telecom wavelengths toward visible and short wavelength regimes, we aim to address the optical control requirements of different quantum platforms.

A central goal is to translate these photonic devices into compact and scalable optical control modules for quantum experiments. To this end, we design, fabricate, and characterize low-loss waveguides, efficient electro-optic modulation, robust optical coupling, and RF-compatible packaging. Photonic design automation plays an increasingly important role in enabling our large-scale and complex circuit architectures. In parallel, we develop coupling and packaging strategies that improve optical access, device stability, and system-level usability. These efforts support the transition from individual devices to integrated photonic modules for scalable quantum control.

Research Track Leader: Dr. Mark Ulanov

Diamond provides attractive material properties for both optical applications and mechanical devices. Especially defects in diamond offer one of the most promising platforms for spin-photonic qubits. They offer a discrete energetic level structure within diamond’s bandgap accessible with photons while also featuring long coherence times due to the low nuclear spin noise in diamond. We use Faraday cage angled etching to create free-standing photonic nanobeam resonators from single crystal diamond substrate. These resonators enable coherent coupling of the defect to our diamond photonic circuitry via the Purcell effect. Since our resonators are made of diamond, defects can be created via focused ion beam (FIB) implantation in the centers of our resonators. This allows for the fabrication of large-scale quantum registers.