Photo of Marco Colangelo

Now-Dr. Marco Colangelo’s thesis defense is now available to view online. The title is “Superconducting Nanowire Technology For Microwave and Photonics Applications.” Congratulations for Dr. Colangelo for his successful PhD defense!


Quantum computing and quantum communication are innovative technologies that promise to revolutionize several aspects of our societal landscape. However, early cutting-edge experiments are rapidly approaching significant scalability roadblocks. As the qubit count increases, superconducting quantum processors require an increasing number of control and readout electronic devices, which are incompatible at scale with the performance of dilution refrigerators. Photonic-based platforms struggle with integration issues due to operational, design, and heterogeneous material compatibility. In this talk, I will demonstrate that superconducting nanowires have the potential to drive a major leap in the scalability of these and other architectures. I will show that the exotic microwave properties of superconducting nanowires enable cryogenic devices at microwave frequencies with an ultra-compact footprint. I will introduce microwave directional couplers and resonators featuring a footprint reduction of up to 200 times, making them suitable for on-chip integration with superconducting quantum processors and any application needing cryogenic microwave signal processing. Furthermore, I will show that engineering the nanowire properties can overcome the metrics trade-offs of single-photon detectors. I will demonstrate an all-in-one nanowire detector with record performances, imaging capabilities, and photon-number resolution capabilities, all in the same design. This device can be used to scale experiments needing many high-performance detectors. Finally, I will demonstrate single-photon detectors integrated on lithium-niobate-on-insulator with state-of-the-art performance. I will also introduce integrated array technology on silicon-on-insulator. This nanowire technology can be heterogeneously integrated with current quantum photonic platforms on-chip, removing the need for outcoupling to fiber-coupled detectors. Superconducting nanowires have the potential to become a comprehensive solution for scaling classical and quantum architectures.

Committee: Prof Karl Berggren (Thesis Supervisor), Prof. Dirk Englund, and Prof. Daniel Santavicca