High-frequency traveling-wave phononic cavity with sub-micron wavelength

作者：Xu, Xin-Biao; Wang, Jia-Qi; Yang, Yuan-Hao; Wang, Weiting; Zhang, Yan-Lei; Wang, Bao-Zhen; Dong, Chun-Hua; Sun, Luyan; Guo, Guang-Can; Zou, Chang-Ling^*

来源：Applied Physics Letters, 2022, 120(16): 163503.

DOI：10.1063/5.0086751

• LITHIUM-NIOBATE
• ELECTRONS
• CIRCUITS
• QUBIT

Thin-film gallium nitride (GaN) is a promising platform for phononic integrated circuits that hold great potential for scalable information processing processors. Here, an unsuspended traveling phononic resonator based on a high-acoustic-index-contrast mechanism is realized in GaN-on-Sapphire with a frequency up to 5 GHz, which matches the typical superconducting qubit frequency. A sixfold increment in quality factor is found when temperature decreases from room temperature (Q = 5000) to 7 K (Q = 30 000), and thus, a frequency-quality factor product of 1.5 x 10(14) is obtained. Higher quality factors should be available when the fabrication process is further optimized. Our system shows great potential in hybrid quantum devices via the so-called circuit quantum acoustodynamics.& nbsp;Published under an exclusive license by AIP Publishing.

• 单位
  南京大学; 清华大学; 中国科学院