Interfacing solid state single emitters with atomic quantum memories

单一的有机分子，如二苯并四氢呋喃(DBT)，是单光子的极佳固态来源。它们的发射波长与Rb中的电子跃迁(780-795 nm)相吻合，在低温下发射线宽达到寿命极限(40 MHz)。因此，使用DBT产生的光子与使用热原子系综和冷原子系综的各种量子存储协议兼容。这个PHD项目将研究如何增强DBT分子的发射，并提高随后从单分子中收集光子的效率。为了做到这一点，我将进行纳米光子建模和制造，以制造波导和腔体结构。然后将使用共聚焦显微镜和激光荧光光谱在低温下对这些材料进行表征。同时，我还将开发用来演示Rb量子存储协议的设备。这将涉及到对量子存储器进行建模，建立温暖的原子蒸气装置，建立磁光陷阱系统来创建冷原子云，以及使用激光的快速强度调制来创建存储和检索光子所需的光脉冲。将研究几种存储协议，包括电磁诱导透明、Autler-Townes分裂、非共振级联吸收和拉曼存储。然后，我将把分子和原子实验结合在一起，演示如何存储和恢复使用原子蒸气使用单个分子产生的光子。此外，还将研究原子频率转换方案，以实现向电信波段光子的有效转换，从而使布里斯托尔大学校园内发生纠缠交换的可能性成为可能。

Single organic molecules such as dibenzoterrylene (DBT) are excellent solid-state sources of single photons. Their emission wavelength coincides with electronic transitions in rubidium (780 - 795 nm) and emission linewidths at low temperature reach the lifetime limit (40 MHz). As such the photons generated using DBT are compatible with various quantum memory protocols using both warm and cold atomic ensembles. This PhD project will investigate routes to enhancing the emission of DBT molecules and increasing the subsequent collection efficiency of photons from single molecules. To do this I will perform nanophotonic modelling and fabrication to make waveguide and cavity structures. These will then be characterized at cryogenic temperature using confocal microscopy and laser fluorescence spectroscopy. Meanwhile, I will develop the apparatus required to demonstrate quantum memory protocols in rubidium. This will involve modelling the quantum memory, building warm atomic vapour setups, building a magneto-optical trap system to create cold clouds of atoms, and using fast intensity modulation of lasers to create the optical pulses needed to store and retrieve photons. Several memory protocols will be investigated including electromagnetically induced transparency, Autler-Townes splitting, off-resonant cascaded absorption, and Raman memories. I will then combine the molecule and atom experiments together to demonstrate the storage and retrieval of photons generated using a single molecule using an atomic vapour. In addition, atomic frequency conversion schemes will be investigated to allow for efficient conversion to telecommunication band photons to enable the possibility of an entanglement swapping across the University of Bristol campus.