Researchers in the group of Professor Tobias J. Kippenberg at EPFL’s School of Basic Sciences have now developed a novel approach that uses light to read out superconducting circuits, thus overcoming the scaling challenges of quantum systems. The work is published in Nature Electronics.
The scientists replaced HEMT amplifiers and coaxial cables with a lithium niobate electro-optical phase modulator and optical fibers respectively. Microwave signals from superconducting circuits modulate a laser carrier and encode information on the output light at cryogenic temperatures. Optical fibers are about 100 times better heat isolators than coaxial cables and are 100 times more compact. This enables the engineering of large-scale quantum systems without requiring enormous cryogenic cooling power. In addition, the direct conversion of microwave signals to the optical domain facilitates long-range transfer and networking between quantum systems.
Youssefi, Amir, Itay Shomroni, Yash J. Joshi, Nathan Bernier, Anton Lukashchuk, Philipp Uhrich, Liu Qiu, Tobias J. Kippenberg. A cryogenic electro-optic interconnect for superconducting devices. Nature Electronics 10 May 2021. DOI: 10.1038/s41928-021-00570-4
More to read: EPFL press release
Image: A cryogenic dilution refrigerator. The base temperature is 10 milliKelvin. Credit: Andrea Bancora, Amir Youssefi