Polisseni Claudio, Major Kyle D, Boissier Sebastien, Grandi Samuele, Clark Alex S, Hinds E A
Opt Express. 2016 Mar 7;24(5):5615-5627. doi: 10.1364/OE.24.005615.
Single dibenzoterrylene (DBT) molecules offer great promise as bright, reliable sources of single photons on demand, capable of integration into solid-state devices. It has been proposed that DBT in anthracene might be placed close to an optical waveguide for this purpose, but so far there have been no demonstrations of sufficiently thin crystals, with a controlled concentration of the dopant molecules. Here we present a method for growing very thin anthracene crystals from super-saturated vapour, which produces crystals of extreme flatness and controlled thickness. We show how this crystal can be doped with an adjustable concentration of dibenzoterrylene (DBT) molecules and we examine the optical properties of these molecules to demonstrate their suitability as quantum emitters in nanophotonic devices. Our measurements show that the molecules are available in the crystal as single quantum emitters, with a well-defined polarisation relative to the crystal axes, making them amenable to alignment with optical nanostructures. We find that the radiative lifetime and saturation intensity vary little within the crystal and are not in any way compromised by the unusual matrix environment. We show that a large fraction of these emitters can be excited more than 10 times without photo-bleaching, making them suitable for real applications.
单个二苯并苝（DBT）分子有望成为按需产生明亮、可靠单光子的光源，并能够集成到固态器件中。为此，有人提出蒽中的DBT可能被放置在靠近光波导的位置，但到目前为止，还没有关于具有可控掺杂分子浓度的足够薄晶体的相关证明。在此，我们展示了一种从过饱和蒸汽中生长非常薄的蒽晶体的方法，该方法能产生极其平整且厚度可控的晶体。我们展示了如何用可调浓度的二苯并苝（DBT）分子对这种晶体进行掺杂，并研究了这些分子的光学性质，以证明它们作为纳米光子器件中的量子发射器的适用性。我们的测量结果表明，晶体中的分子作为单个量子发射器存在，相对于晶体轴具有明确的极化方向，这使得它们易于与光学纳米结构对齐。我们发现，辐射寿命和饱和强度在晶体内变化很小，并且丝毫不受异常基质环境的影响。我们表明，这些发射器中的很大一部分可以被激发10次以上而不发生光漂白，使其适用于实际应用。
