CSU achieves tunable microwave-optical wave conversion using magneto-optical hybrid quantum system
Academician Guangcan Guo's team has made new progress in the study of magneto-optical force hybrid systems. The team's research group of Prof. Chunhua Dong put the optical force microcavity in direct contact with the magnetic oscillator microcavity and demonstrated that the hybrid system supports coherent magneto-phonon-photon coupling, which in turn enables tunable microwave-optical wave conversion. The research results were published in the international academic journal Physics Review Letters on Dec. 9, 2022.
Different quantum systems are suitable for different quantum operations, including atomic and solid-state systems such as rare-earth doped crystals, superconducting circuits, yttrium-iron garnet (YIG) or spin in diamond. By using phonons as an intermediate medium, coupling and regulation of different quantum systems can be achieved, and eventually hybrid quantum networks that can take advantage of different quantum systems can be constructed. Currently, optical radiation pressure, electrostatic force, magnetostrictive effect, and piezoelectric effect have been widely used to couple mechanical phonons with optical photons, microwave photons, or magnetons. These interaction mechanisms have contributed to the rapid development of the opto-mechanical field and the magneto-mechanical field. In the previous work, the research group has realized tunable single-sideband microwave-optical wave conversion by taking advantage of the good tunable properties of magnetic oscillators in YIG microcavities in combination with the magneto-optical effect (Photonics Research 10, 820 (2022)). However, the large mode size and quality factor of the current magneto-optical crystal microcavities make it difficult to further break through, thus limiting the magneto-optical interaction strength and leading to low microwave-optical wave conversion efficiency. In contrast, the cavity-optical force system has achieved efficient microwave-optical wave conversion, but it will be limited in practical applications due to the lack of tunability.
Figure Notes: a-b. Schematic diagram of the magneto-photonic hybrid system supporting magneto-phonon-photon coherent coupling; c. Microwave-optical wave conversion.
In this work, the research group developed a hybrid system consisting of a photonic force microcavity and a magnetic oscillator microcavity. In the system, phonons can be manipulated electrically by magnetostrictive effect and optically by optical radiation pressure, and phonons in different microcavities can be coherently coupled by direct contact of the microcavities. Based on the sensitive measurement of mechanical states by high-quality optical modes, the group achieved microwave-optical conversion in the tuning range up to 3 GHz, and the conversion efficiency is much higher than that of previous magneto-optical single systems. In addition, the group observed the interference effect of mechanical motion, in which the optically driven mechanical motion can be canceled by the microwave-driven coherent mechanical motion. Overall, this magneto-optical force system provides a hybrid experimental platform to effectively perform manipulation of light, sound, electricity and magnetism, and is expected to play an important role in the construction of hybrid quantum networks.
Zhen Shen, Guanting Xu, and Mai Zhang are the co-first authors of the paper, and Chunhua Dong is the corresponding author of the paper. The above research was supported by the Key Research and Development Program of the Ministry of Science and Technology, the Chinese Academy of Sciences, the National Natural Science Foundation of China, and the Collaborative Innovation Center of Quantum Information and Quantum Science and Technology Frontier.
Link to the paper：
https://link.aps.org/doi/10.1103/PhysRevLett.129.24360
