High-speed programmable photonic circuits in a cryogenically compatible, visible–near-infrared 200 mm CMOS architecture

• Published in: Nature photonics Vol. 16; no. 1; pp. 59 - 65
• Main Authors: Dong, Mark, Clark, Genevieve, Leenheer, Andrew J., Zimmermann, Matthew, Dominguez, Daniel, Menssen, Adrian J., Heim, David, Gilbert, Gerald, Englund, Dirk, Eichenfield, Matt
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 2022; Nature Publishing Group
• Subjects: 142/126; 639/624/1075/1079; 639/624/399/1099; Aluminum; Aluminum nitride; Applied and Technical Physics; CMOS; Computer architecture; Cryogenic temperature; Data processing; I.R. radiation; Information processing; Integrated circuits; Learning algorithms; Mach-Zehnder interferometers; Machine learning; Phase modulation; Phase shifters; Photonics; Physics; Physics and Astronomy; Piezoelectric actuators; Power consumption; Power management; Quantum phenomena; Quantum Physics; Silicon; Silicon nitride; Wave propagation; Waveguides; Wavelengths
• ISSN: 1749-4885; 1749-4893
• DOI: 10.1038/s41566-021-00903-x

Recent advances in photonic integrated circuits have enabled a new generation of programmable Mach–Zehnder meshes (MZMs) realized by using cascaded Mach–Zehnder interferometers capable of universal linear-optical transformations on N input/output optical modes. MZMs serve critical functions in photonic quantum information processing, quantum-enhanced sensor networks, machine learning and other applications. However, MZM implementations reported to date rely on thermo-optic phase shifters, which limit applications due to slow response times and high power consumption. Here we introduce a large-scale MZM platform made in a 200 mm complementary metal–oxide–semiconductor foundry, which uses aluminium nitride piezo-optomechanical actuators coupled to silicon nitride waveguides, enabling low-loss propagation with phase modulation at greater than 100 MHz in the visible–near-infrared wavelengths. Moreover, the vanishingly low hold-power consumption of the piezo-actuators enables these photonic integrated circuits to operate at cryogenic temperatures, paving the way for a fully integrated device architecture for a range of quantum applications. A four-port programmable interferometer based on aluminium nitride piezo-optomechanical actuators coupled to silicon nitride waveguides is reported. Its low-power mechanism, which can be fabricated in a complementary metal–oxide–semiconductor foundry, facilitates operation at cryogenic temperatures.