基于激光偏振优化的NV色心测温性能提升方法OA

With the development of quantum precision measurement technology,the temperature measurement method of nitrogen-vacancy(NV)centers in diamond based on solid-state quantum spin is expected to break through the bottleneck of non-destructive microscopic temperature detection technology in biomedical and chip manufacturing fields,due to its merits of ultra-high precision,micro-nano scale,stable material properties and so on.However,the method to enhance the signal-to-noise ratio by applying high-power lasers or microwave lead to significant heating effects,thereby affecting the precision of temperature measurement.To avoid increasing the external field power,a method of optimizing the polarization direction of pumping laser is proposed to improve measurement performance.Firstly,the influence of laser polarization on the electron spin polarization ratio and fluorescence contrast is theoretically analyzed,and a light path which can adjust the polarization of pumping light is designed.Moreover,`experiments are conducted to investigate the variation of fluorescence contrast along the four NV axes as a function of laser polarization direction,the optimal polarization direction is selected for optimizing microwave power and temperature measurement sensitivity.Experimental results show that the proposed method effectively reduces the required microwave power,lowers thermal heating by～7 ℃ and enhances temperature sensitivity over threefold.