论文标题
弱热状态正交噪声影像
Weak Thermal State Quadrature-Noise Shadow Imaging
论文作者
论文摘要
在这项工作中，我们从理论上和实验上证明了使用几个光子热光场创建不透明对象的图像的可能性。我们利用了正交噪声影像成像（QSI）技术，该技术在与对象相互作用后检测探针梁的正交统计的变化。我们表明，当考虑黑暗计数的效果时，这种热QSI方案比经典差异成像具有优势。同时，任何波长的热源的易于可用性使得该方法适用于广泛的应用，而无法使用，例如量子挤压光。作为原则的证明，我们通过两个不同的光源实现了此方案：通过旋转地面玻璃（RGG）方法生成的伪热光束和四波混合（FWM）方法产生的热束。 RGG方法显示出QSI方案的简单性和鲁棒性，而FWM方法验证了理论信噪比预测。最后，我们通过在CCD摄像头上成像生物样品来证明使用QSI的低光成像能力，每1.7微秒暴露的平均每个像素平均检测到低至0.03的光子。
In this work, we theoretically and experimentally demonstrate the possibility to create an image of an opaque object using a few-photon thermal optical field. We utilize the Quadrature-Noise Shadow Imaging (QSI) technique that detects the changes in the quadrature-noise statistics of the probe beam after its interaction with an object. We show that such thermal QSI scheme has an advantage over the classical differential imaging when the effect of dark counts is considered. At the same time, the easy availability of thermal sources for any wavelength makes the method practical for broad range of applications, not accessible with, e.g. quantum squeezed light. As a proof of principle, we implement this scheme by two different light sources: a pseudo-thermal beam generated by rotating ground glass (RGG) method and a thermal beam generated by Four-Wave Mixing (FWM) method. The RGG method shows simplicity and robustness of QSI scheme while the FWM method validates theoretical signal-to-noise ratio predictions. Finally, we demonstrate low-light imaging abilities with QSI by imaging a biological specimen on a CCD camera, detecting as low as 0.03 photons on average per pixel per 1.7 microseconds exposure.
