Target Detection Systems]{}

INTRODUCTION
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Optical target detection has been receiving increasing attention owing to many emerging applications in the domains of computing, human/machine interaction, LIDAR, and non-invasive biological imaging, amongst others. Conventionally, the sensitivity of optical target detection could be improved by increasing the source brightness, detector sensitivity or improving the throughput of the optical setup. In addition, computational imaging has been providing astounding advantages to the fidelity of various imaging modalities [@gariepy2016detection], those can be utilized on top of any hardware improvement brought about due to enhanced device performance. Recent work has also explored the extension of target detection techniques and equipment to novel illumination wavelengths suitable for remote sensing of distant objects [@barzanjeh2015microwave]. Practical platforms for these purposes will find applications in sensing, surveillance, and autonomous driving.

Aside from the aforementioned approaches, a novel and radical way to improve the target detection performance is to use a non-classical state of light as the source. Current LIDAR systems are based on illumination sources that can be described by classical electromagnetism. However, the properties of classical states of electromagnetic radiation pose ultimate limits, such as the thermal and shot noise. On the other hand, non-classical states of electromagnetic radiation 