.png){kind=icon}
.png){kind=icon}
Return
Temperature-Switch-Controlled Second Harmonic Mode Sensor for Brain-Tissue Detection
.png){kind=icon}
OA
AI
DOI：10.3390/s24103065.png)
.png){kind=icon}
.png){kind=icon}
Share.png){kind=icon}
Save
Abstract
En 中文
Identifying brain-tissue types holds significant research value in the biomedical field of non-contact brain-tissue measurement applications. In this paper, a layered metastructure is proposed, and the second harmonic generation (SHG) in a multilayer metastructure is derived using the transfer matrix method. With the SHG conversion efficiency (CE) as the measurement signal, the refractive index ranges that can be distinguished are 1.23 similar to 1.31 refractive index unit (RIU) and 1.38 similar to 1.44 RIU, with sensitivities of 0.8597 RIU-1 and 1.2967 RIU-1, respectively. It can distinguish various brain tissues, including gray matter, white matter, and low-grade glioma, achieving the function of a second harmonic mode sensor (SHMS). Furthermore, temperature has a significant impact on the SHG CE, which can be used to define the switch signal indicating whether the SHMS is functioning properly. When the temperature range is 291.4 similar to 307.9 Kelvin (K), the temperature switch is in the open state, and the optimal SHG CE is higher than 0.298%, indicating that the SHMS is in the working state. For other temperature ranges, the SHG CE will decrease significantly, indicating that the temperature switch is in the off state, and the SHMS is not working. By stimulating temperature and using the response of SHG CE, the temperature-switch function is achieved, providing a new approach for temperature-controlled second harmonic detection.
Keywords:
second harmonic generation
temperature switch
layered second harmonic generation (SHG)
as a frequency-doubling phenomenon
plays a crucial role in metastructure
conversion efficiency
transfer matrix method
AI Summary
Key information extracted from the uploaded paper, including a brief overview, abstract, background, key highlights, visual analysis, and future outlook.