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A theoretical model of nuclear magnetic resonance gyroscope (NMRG) has been established in this paper by the double noble gases in closed loop. The effect on the accuracy of NMRG by the external static magnetic field was analyzed. The fluctuation of the static magnetic field causes measurement error in the Earth’s rotary rate experiment. The atoms sense a constant magnetic field, when the fluctuation of the static magnetic field is compensated by the closed loop system. The results show that the Earth’s rotary rate measurement error decreases from 13.58 to 0.22°/h, which means 62 times, when the static magnetic field is compensated in closed loop. The fluctuation of the static magnetic field in the magnetic shield decreases 571 times. A higher accuracy of the NMRG is achieved when the fluctuation of the static magnetic field is effectively suppressed by the closed loop.

Experimental setup of long distance and high resolution single-pixel imaging system was set up. Images of natural target were obtained through 34 km outdoors horizontal atmosphere in daylight, about 0.8 m resolution was achieved. The multiple resolution level of Hadamard matrix was used as measurement basis, and owing to 25% compressive sampling and differential measuring by two photon-multiplier tubes, video frame rate of 2 Hz@128128 pixels was achieved with the proposed hardware and fast Walsh transform algorithm. An signal-to-noise ratio(SNR) was defined based on human-computer interaction interface to estimate the qualities of the recovered images. The relationship between image qualities and exposure times were researched. The proposed scheme has the potential application in long distance and high resolution infrared imaging with low cost setup.

Since its first experimental demonstration in 1995, ghost imaging has attracted a great deal of attention due to its potential applications. In Yanhua Shih’s paper (Meyers R E, Deacon K S, Shih Y H 2011 Appl. Phys. Lett. 98 111115; Meyers R E, Deacon K S, Shih Y H 2012 Appl. Phys. Lett. 100 131114), he pointed out that " one of the useful features is the turbulence insensitivity of thermal light ghost imaging, i.e., atmospheric turbulence would not have any influence on the ghost images of sunlight”. However, in Jeffrey H. Shapiro’s view (Shapiro J H 2012 arXiv:1201.4513 [quant-ph]), lens-less pseudo-thermal ghost imaging is not immune to spatial resolution loss from the presence of atmospheric turbulence along the propagation paths, unless the source diameter is less than the source-plane turbulence coherence length. In the present paper, we find that the second order self-correlation of sunlight intensity is the case that can be satisfied with both theories of Shih and Shapiro. In this paper, the second order self-correlation of sunlight intensity (the intensity variance of the images acquired by the CCD camera), rather than the total intensity correlation between images and bucket detector signals (the traditional ghost imaging method), is calculated to recover the high-quality images in turbulent atmosphere under a few hundred measurements. Inspired by Boyd’s paper, titled " thermal ghost imaging with averaged speckle patterns” (Zerom P, Shi Z, O’Sullivan M N, Chan K W C, Krogstad M, Shapiro J H, Boyd R W 2012 Phys. Rev. A 86 063817), turbulence insensitivity of sunlight ghost imaging is demonstrated both theoretically and experimentally in this article. It is found that thermal ghost imaging system whose coherence time need not to be controlled to match the speed of the detectors, ghost imaging with sunlight, which has always been considered intriguing and highly desirable, now is realizable. We present theoretical and experimental results showing that a sunlight self-correlation ghost imaging system can produce high-quality images even when it uses an slow detector and passes through the turbulence near ground, as long as the signal variation is predominantly caused by the fluctuation of the sunlight intensity rather than other noise sources. Our scheme can also be used to improve the image quality in other wave bands such as infrared and ultraviolet, in the case where an poor image quality results from the turbulence or other random disturbances on the wavefront.