911制品厂麻花

News

Breakthrough in superconducting technology: NJU researchers develop integrated microwave frequency comb

Researchers from the Institute of Superconducting Electronics at the School of Electronics, Nanjing University, have recently published a groundbreaking study in Nature Communications. They have demonstrated a fully integrated and DC-powered superconducting microwave frequency comb signal source. This innovation is not only easy to manufacture and operate but also boasts extremely low energy consumption. It promises to be a critical signal source for on-chip integrated quantum chips, thereby advancing the integration and error correction technology in quantum computing.

A frequency comb is a special laser source capable of emitting multiple equidistant spectral lines and is widely used in high-precision applications such as optical clocks, lidar, spectroscopy, and optical neural networks. While on-chip integrated frequency combs have made significant progress in the optical domain, achieving fully on-chip integrated frequency combs in the microwave domain remains challenging. To address these challenges, the research team developed an on-chip integrated microwave frequency comb signal source based on superconducting materials. This device generates microwave signals with a series of equidistant spectral lines in the frequency domain and a series of highly coherent pulse microwave signals in the time domain. The device is simple in structure, easy to operate, and driven by an ultra-low power DC signal.

Image courtesy of Yong-Lei Wang, Research Institute of Superconductor Electronics, Nanjing University


The core of this research is a superconducting frequency comb signal source, directly coupled from a Josephson junction to a superconducting coplanar waveguide resonator. By using a simple DC bias power supply, the researchers successfully achieved self-starting mode locking of the frequency comb with a power consumption of only tens of picowatts. Operating in the microwave domain, the linewidth of this micro comb can be reduced to within 1 Hz using a unique coherent injection locking technique, thereby achieving high-precision frequency control.

This breakthrough has significant applications in the field of quantum computing. It can be used to develop low-cost on-chip integrated arbitrary waveform generators, bringing substantial transformations to future quantum technology applications. As a signal source for on-chip integrated quantum chips, the superconducting microwave frequency comb can significantly reduce the cost, size, and energy consumption of quantum computing, as well as the difficulty of error correction, promoting the development and application of large-scale integrated general-purpose quantum computing.

Professor Yong-Lei Wang from the School of Electronic Science and Engineering at Nanjing University stated, "The superconducting frequency comb we developed is not only extremely energy-efficient but also perfectly compatible with existing superconducting quantum circuits. Our goal is to further optimize the performance and functionality of this device to meet the needs of quantum computing, integrating it with qubits for practical quantum computing systems."

The research team plans to continue optimizing the performance of the superconducting micro comb and exploring its applications in quantum technology. For example, by integrating it with tunable frequency superconducting resonators, researchers aim to achieve higher precision frequency control and waveform generation. Additionally, the team will explore the realization of superconducting frequency combs in the terahertz band with high-temperature superconductors, potentially extending the operating temperature range of this technology.

The first author of this work is Wang Chenguang, a doctoral student at the School of Electronic Science and Engineering, Nanjing University. Professors Yong-Lei Wang, Huabing Wang, and Academician Peiheng Wu from Nanjing University are the corresponding authors. This work was supported by the National Natural Science Foundation of China, the National Key R&D Program, the Purple Mountain Laboratories, and the National Key Laboratory of Spintronics.

Publication: Integrated and DC-powered superconducting microcomb

Chen-Guang Wang, Wuyue Xu, Chong Li, Lili Shi, Junliang Jiang, Tingting Guo, Wen-Cheng Yue, Tianyu Li, Ping Zhang, Yang-Yang Lyu, Jiazheng Pan, Xiuhao Deng, Ying Dong, Xuecou Tu, Sining Dong, Chunhai Cao, Labao Zhang, Xiaoqing Jia, Guozhu Sun, Lin Kang, Jian Chen, Yong-Lei Wang*, Huabing Wang*, Peiheng Wu*

Nature Communications 15, 4009 (2024)

DOI Foundation-024-48224-1



Source: School of Electronic Science and Engineering

Correspondent: Wang Yonglei