Linear and phase controllable terahertz frequency conversion via ultrafast breaking the bond of a meta-molecule

Siyu Duan; Xin Su; Hongsong Qiu; Yushun Jiang; Jingbo Wu; Kebin Fan; Caihong Zhang; Xiaoqing Jia; Guanghao Zhu; Lin Kang; Xinglong Wu; Huabing Wang; Keyu Xia; Biaobing Jin; Jian Chen; Peiheng Wu

doi:10.1038/s41467-024-45416-7

Linear and phase controllable terahertz frequency conversion via ultrafast breaking the bond of a meta-molecule

Nat Commun. 2024 Feb 6;15(1):1119. doi: 10.1038/s41467-024-45416-7.

Authors

Siyu Duan^{1

2}, Xin Su^{1

3}, Hongsong Qiu¹, Yushun Jiang¹, Jingbo Wu^{4

5}, Kebin Fan^{1

2}, Caihong Zhang^{1

2}, Xiaoqing Jia^{1

2}, Guanghao Zhu¹, Lin Kang^{1

2}, Xinglong Wu^{6

7}, Huabing Wang^{1

2}, Keyu Xia^{8

9

10}, Biaobing Jin^{11

12}, Jian Chen^{1

2}, Peiheng Wu^{1

2}

Affiliations

¹ Research Institute of Superconductor Electronics (RISE) & Key Laboratory of Optoelectronic Devices and Systems with Extreme Performances of MOE, School of Electronic Science and Engineering, Nanjing University, Nanjing, 210023, China.
² Purple Mountain Laboratories, Nanjing, 211111, China.
³ College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210023, China.
⁴ Research Institute of Superconductor Electronics (RISE) & Key Laboratory of Optoelectronic Devices and Systems with Extreme Performances of MOE, School of Electronic Science and Engineering, Nanjing University, Nanjing, 210023, China. jbwu@nju.edu.cn.
⁵ Purple Mountain Laboratories, Nanjing, 211111, China. jbwu@nju.edu.cn.
⁶ National Laboratory of Solid State Microstructures, Nanjing University, Nanjing, 210093, China.
⁷ School of Physics, Nanjing University, Nanjing, 210093, China.
⁸ College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210023, China. keyu.xia@nju.edu.cn.
⁹ National Laboratory of Solid State Microstructures, Nanjing University, Nanjing, 210093, China. keyu.xia@nju.edu.cn.
¹⁰ Shishan Laboratory, Suzhou Campus of Nanjing University, Suzhou, 215000, China. keyu.xia@nju.edu.cn.
¹¹ Research Institute of Superconductor Electronics (RISE) & Key Laboratory of Optoelectronic Devices and Systems with Extreme Performances of MOE, School of Electronic Science and Engineering, Nanjing University, Nanjing, 210023, China. bbjin@nju.edu.cn.
¹² Purple Mountain Laboratories, Nanjing, 211111, China. bbjin@nju.edu.cn.

Abstract

The metasurface platform with time-varying characteristics has emerged as a promising avenue for exploring exotic physics associated with Floquet materials and for designing photonic devices like linear frequency converters. However, the limited availability of materials with ultrafast responses hinders their applications in the terahertz range. Here we present a time-varying metasurface comprising an array of superconductor-metal hybrid meta-molecules. Each meta-molecule consists of two meta-atoms that are "bonded" together by double superconducting microbridges. Through experimental investigations, we demonstrate high-efficiency linear terahertz frequency conversion by rapidly breaking the bond using a coherent ultrashort terahertz pump pulse. The frequency and relative phase of the converted wave exhibit strong dependence on the pump-probe delay, indicating phase controllable wave conversion. The dynamics of the meta-molecules during the frequency conversion process are comprehensively understood using a time-varying coupled mode model. This research not only opens up new possibilities for developing innovative terahertz sources but also provides opportunities for exploring topological dynamics and Floquet physics within metasurfaces.