The field of quantum sensing aims at improving the detection and estimation of classical parameters that are encoded in physical systems by resorting to quantum sources of light and quantum detection strategies. The same approach can be used to improve the current classical measurements that are performed on biological systems. Here we consider the scenario of two bacteria (E. coli and Salmonella) growing in a Luria-Bertani broth and monitored by classical spectrophotometers. Their concentration can be related to the optical transmissivity via the Beer-Lambert-Bouguer's law and their growth curves can be described by means of Gompertz functions. Starting from experimental data points, we extrapolate the growth curves of the two bacteria and we study the theoretical performance that would be achieved with a quantum setup. In particular, we discuss how the bacterial growth can in principle be tracked by irradiating the samples with orders of magnitude fewer photons, identifying the clear superiority of quantum light in the early stages of growth. We then show the superiority and the limits of quantum resources in two basic tasks: (i) the early detection of bacterial growth and (ii) the early discrimination between two bacteria species.

中文翻译：

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用量子光检测和跟踪细菌

量子感测领域旨在通过利用光的量子源和量子检测策略来改进对物理系统中编码的经典参数的检测和估计。可以使用相同的方法来改进当前在生物系统上执行的经典测量。在这里，我们考虑两种细菌（大肠杆菌和沙门氏菌）在Luria-Bertani肉汤中生长，并通过经典分光光度计进行监控。它们的浓度可以通过比尔-朗伯-布格定律与光学透射率相关，并且它们的生长曲线可以通过Gompertz函数描述。从实验数据出发，我们推断了这两种细菌的​​生长曲线，并研究了通过量子设置可以实现的理论性能。特别是，我们讨论了原理上如何通过以更少的光子数量级照射样品来跟踪细菌的生长，从而确定了量子光在生长早期的明显优势。然后，我们在两个基本任务中显示了量子资源的优越性和局限性：（i）细菌生长的早期检测和（ii）两种细菌物种之间的早期区分。