The study of quantum spectral imaging

Research and development of short-range quantum infrared detector

“…With the development of science and technology, the requirement of measurement accuracy is higher and higher.In classical physics, the detection of any physical quantity is accompanied by noise, including the classical noise of the system and quantum noise, which limits the detection accuracy.The classical noise mainly comes from the technical defects, the quality of instruments and other factors.However, with the rapid development of technology, the classical noise of the system is greatly reduced, often negligible.Therefore, quantum noise determined by quantum mechanical properties gradually becomes the main source of noise [1] .Before the appearance of the squeezed optical field, the coherent state is the classical optical field with the least noise, which only contains quantum noise. Its noise power is exactly the basis of shot noise, and it is symmetrically distributed in the two orthogonal components of orthogonal amplitude and orthogonal phase [2] .The squeezed state is to redistribute the noise of the coherent state symsymically distributed among the quadrature amplitude components and quadrature phase components in a way that does not violate the Heisenberg Uncertainty Principle so that the noise power of one quadrature component is lower than that of the shot noise reference and the noise power of the other quadrature component is higher than the shot noise reference.According to the characteristics of the squeezed light state field, when the noise of the squeezed light state field is less than the orthogonal component of the shot noise reference, the measurement accuracy can be exceeded by the shot noise reference, and the detection sensitivity beyond the quantum noise limit can be obtained [3] .…”