Remer Itay, Cohen Lear, Bilenca Alberto
Biomedical Engineering Department, Ben-Gurion University of the Negev.
Biomedical Engineering Department, Ben-Gurion University of the Negev; Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev;
J Vis Exp. 2017 Sep 22(127):55527. doi: 10.3791/55527.
Recent years have witnessed a significant increase in the use of spontaneous Brillouin spectrometers for non-contact analysis of soft matter, such as aqueous solutions and biomaterials, with fast acquisition times. Here, we discuss the assembly and operation of a Brillouin spectrometer that uses stimulated Brillouin scattering (SBS) to measure stimulated Brillouin gain (SBG) spectra of water and lipid emulsion-based tissue-like samples in transmission mode with <10 MHz spectral-resolution and <35 MHz Brillouin-shift measurement precision at <100 ms. The spectrometer consists of two nearly counter-propagating continuous-wave (CW) narrow-linewidth lasers at 780 nm whose frequency detuning is scanned through the material Brillouin shift. By using an ultra-narrowband hot rubidium-85 vapor notch filter and a phase-sensitive detector, the signal-to-noise-ratio of the SBG signal is significantly enhanced compared to that obtained with existing CW-SBS spectrometers. This improvement enables measurement of SBG spectra with up to 100-fold faster acquisition times, thereby facilitating high spectral-resolution and high-precision Brillouin analysis of soft materials at high speed.
近年来，自发布里渊光谱仪在对软物质（如水溶液和生物材料）进行非接触分析时的使用显著增加，且采集时间很快。在此，我们讨论一种布里渊光谱仪的组装和操作，该光谱仪利用受激布里渊散射（SBS）在透射模式下测量水和基于脂质乳液的类组织样品的受激布里渊增益（SBG）光谱，光谱分辨率小于10 MHz，布里渊频移测量精度小于35 MHz，采集时间小于100 ms。该光谱仪由两个波长为780 nm的近反向传播连续波（CW）窄线宽激光器组成，其频率失谐通过材料布里渊频移进行扫描。通过使用超窄带热铷 - 85蒸汽陷波滤波器和相敏探测器，与现有连续波 - SBS光谱仪相比，SBG信号的信噪比显著提高。这一改进使得能够以快达100倍的采集时间测量SBG光谱，从而有助于对软材料进行高速的高光谱分辨率和高精度布里渊分析。
