An ultra-compact ultrasound sensor with a chalcogenide (ChG) microfiber and a silica microfiber is fabricated. It can detect the ultrasound wave generated by a piezoelectric transducer peaked at 3.7 MHz. The sensor shows the broadband ultrasound frequency response with a high signal-to-noise ratio (SNR), owing to the high refractive index and small Young's modulus of ChG material. A ChG (${{\rm As}_2}{{\rm Se}_3}$As2Se3) microfiber of 2 µm diameter is adhered to the surface of a silica microfiber with a diameter of 5 µm via Van der Waals force; the transmission spectrum has high contrast due to multi-mode interference in this hybrid structure. The SNR response could be up to 70 dB, especially at low frequency due to the soft ChG microfiber as a sensing unit to magnify the ultrasound signal, along with an SNR over 12 dB at ultrasound of 31.2 MHz. As a comparison, a silica taper with the same size as the ChG microfiber is also placed on the silica microfiber with a diameter of 5 µm to detect an ultrasound signal from 18 kHz to 9.4 MHz with an SNR lower than that based on the ChG microfiber up to 38.8 dB, showing the high sensitivity of the ChG microfiber.

中文翻译：

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硫属化物超细纤维辅助的二氧化硅超细纤维用于超声检测。

制备了具有硫族化物（ChG）微纤维和二氧化硅微纤维的超紧凑型超声传感器。它可以检测到峰值为3.7 MHz的压电换能器产生的超声波。由于ChG材料的高折射率和小杨氏模量，该传感器显示出具有高信噪比（SNR）的宽带超声频率响应。通过范德华力将直径为2 µm的ChG（$ {{\ rm As} _2} {{\ rm Se} _3} $ As2Se3）超细纤维粘附到直径为5 µm的二氧化硅微纤维的表面上；在这种混合结构中，由于多模干扰，透射光谱具有很高的对比度。SNR响应可能高达70 dB，特别是在低频下，这是由于柔软的ChG超细纤维作为传感单元来放大超声信号，以及在31超声时SNR超过12 dB。2 MHz。作为比较，在直径为5 µm的二氧化硅微纤维上也放置了与ChG微纤维相同尺寸的二氧化硅锥度，以检测18 kHz至9.4 MHz的超声信号，其SNR低于基于ChG微纤维的SNR。高达38.8 dB，显示了ChG超细纤维的高灵敏度。