Compound Semiconductor Optical Sources for Atomic Sensors

目的：开发基于碱蒸气的芯片级原子传感器所需的光源，包括时钟和磁强计。准确测量时间是运输、通信、金融交易、安全和可靠能源等服务有效运行的基础。目前，全球导航卫星系统(GNSS)为这些关键基础设施服务提供授时信号，但容易受到干扰。需要广泛分布的微型原子钟，以便在停电时提供计时基准。磁场测量需要达到皮特斯拉精度的磁场测量，用于地球物理测绘、水下秩序探测和监测人体内产生的电脉冲。目前的磁强计体积很大，在运行中会消耗大量的功率。化合物半导体(CS)光源可以在减小体积和重量的同时显著降低功耗。下一代芯片级原子传感器使用一种被称为相干布居捕获的效应，需要具有特定特性的可靠光源。垂直腔面发射激光器(VCSEL)是一种结构紧凑、节能的新型半导体激光器。这是一个参与广泛活动的机会，开发新的方法来确保CS光源的目标规格能够实现。

Aim: Develop optical sources required for alkali-vapour based chip-scale atomic sensors, including clocks and magnetometers.Precise measurement of time is fundamental to the effective functioning of services such as transport links, communications, financial transactions, security and reliable energy. Currently, Global Navigation Satellite Systems (GNSS) provide the timing signal for these critical infrastructure services, but is vulnerable to disruption. There is a need for wide-spread miniaturised atomic clocks to provide a timing reference in the event of an outage.Magnetic field measurements, to pico-Tesla precision is required for applications in geophysical mapping, underwater ordinance detection and monitoring electrical pulses generated within the human body. Current magnetometer are bulky and dissipate substantial power in operation. Compound semiconductor (CS) light sources could reduce this power consumption significantly, whilst reducing the size and weight.Next generation chip-scale atomic sensors, using an effect know as coherent-population-trapping, require a reliable optical source with specific characteristics. Vertical-Cavity Surface-Emitting Lasers (VCSELs) are currently being considered which are compact and energy efficient. Here is an opportunity to take part in a wide-reaching activity, developing novel ways to ensure that target specifications of CS optical sources can be achieved.