Reviewed by Lexie CornerMay 14 2024
Researchers at the University of Electronic Science and Technology of China (UESTC) published a study in Frontiers of Optoelectronics on a new gas sensor design. This design utilizes a sub-comb state with graphene sensitization, achieving ultra-high sensitivity for gas detection down to parts per billion levels.
Embodiment and operating principle of graphene-sensitized sub-comb sensing. Image Credit: Yupei Liang, Mingyu Liu, Fan Tang, Yanhong Guo, Hao Zhang, Shihan Liu, Yanping Yang, Guangming Zhao, Teng Tan, Baicheng Yao
Research on the coherent soliton state has been extremely active since the invention of the microcomb, whose generation depends on Kerr nonlinearity in the microresonator.
Sub-comb outputs are simple to operate as noncoherent comb states, but they were frequently disregarded in earlier methods. This sub-comb heterodyne sensing device shows remarkable response to gas molecular adsorption with graphene sensitization, achieving detect limits of 1.2 ppb for H2S gas and 1.4 ppb for SO2 gas, respectively.
The study combines graphene optoelectronics, direct offset heterodyne detection, and flexible comb formation to create a tiny, highly sensitive gas sensor that is simple to use. This investigation not only provides a straightforward setup for the system but also establishes a new benchmark for easy optoelectronic detection.
Beyond its use in microsphere-based gas sensing, the multidisciplinary approach holds the potential for offering platform-independent solutions for a wider range of sensing applications, such as photonic-microwave signal generation and control and on-chip biochemical sensing.
Researchers, led by Professor Baicheng Yao, are interested in optical fiber sensors and frequency comb technology. Optical fiber sensors are valued for their miniature size, while frequency comb technology offers exceptional precision and stability. Their strategy involves utilizing the formation dynamics of sub-comb states, which provide a stable and detectable signal for gas sensing and are easily accessible. This signal is enhanced through the sensitization effect of graphene, leading to an exceptional response to analytes.
Journal Reference:
Liang, Y., et al. (2024) Harnessing sub-comb dynamics in a graphene-sensitized microresonator for gas detection. Frontiers of Optoelectronics. doi.org/10.1007/s12200-024-00115-5.