Advanced Spectroscopic Techniques for Separating Natural and Synthetic Diamond Gemstones

确切地知道一颗钻石的来源，对确定它的价值至关重要。这个问题比钻石是人造的还是天然的要深入得多。关于宝石来源的信息越来越重要，因为它可以向消费者保证，他们的钻石来源符合道德规范，并且在整个生产过程中都保持了最佳实践。合成宝石级金刚石材料现在可以通过高压高温（HPHT）或化学气相沉积（CVD）生长方法生产。然而，由于天然未经处理的钻石比经过处理的钻石或合成钻石更有价值，因此需要让客户确信，可以高度自信地检测到未公开的合成钻石。光谱学是宝石学家最强大的分析武器之一，因为它可以以一种可量化和可复制的方式记录宝石的光学特性。该技术本身也是无损的。某些光学特征会引起怀疑，表明存在额外的元素，或点和扩展缺陷，在天然钻石中不常见。同样，某些光学特征可以揭示晶体形成时生长条件的线索，天然钻石和人造钻石的生长条件将有很大不同。随着人造钻石质量的不断提高，开发更先进的光谱检测技术以保持领先地位变得越来越重要。该项目将由Georgina Klemencic博士（卡迪夫）、Stephen Lynch博士（卡迪夫）和Colin McGuinness博士（戴比尔斯）监督。卡迪夫大学和戴比尔斯之前曾密切合作，以了解在合成宝石中发现的不寻常的光谱特征。这个项目将以这项工作的遗产为基础。我们正在寻找一名学生继续开发光谱成像实验，该实验能够在一定时间尺度和温度范围内探索脉冲紫外线照射下金刚石的发光行为。预计学生每年将花6周的时间在梅登黑德的戴比尔斯研究实验室验证他们的工作。因此，这个博士项目提供了一个令人兴奋的机会来进行尖端的物理研究，也与工业相关。在戴比尔斯工作期间，学生将接受独特的定制培训，他们将能够体验跨国公司的研发环境。

Knowing the origin or provenance of a diamond gemstone with certainty is critical to determining its value. This question goes deeper than whether the diamond is of synthetic or natural origin. Information about a gemstone's provenance is increasingly important in reassuring the consumer that their diamond has been ethically sourced and that best practice has been maintained throughout its production.Synthetic gemstone-quality diamond material can now be produced by high pressure high temperature (HPHT) or chemical vapor deposition (CVD) growth methods. However, since natural untreated diamonds are valued above treated diamonds or synthetics, customers need to be convinced that undisclosed synthetics can be detected with a high degree of confidence. One ofthe most powerful analytical weapons in the gemmologist's armoury is optical spectroscopy because it can record the optical characteristics of a gemstone in a quantifiable and reproducible way. The technique is also inherently non-destructive. Certain optical signatures will raise suspicion by indicating the presence of additional elements, or point and extended defects, not commonly found in natural diamonds. Likewise, certain optical signatures can reveal clues about the growth conditions when the crystal was forming, conditions that will be significantly different for natural and synthetic diamonds. As the quality of synthetic diamond gemstones continues to improve, it is increasingly important to develop more advanced spectroscopic interrogation techniques to keep ahead. This project will be supervised by Dr Georgina Klemencic (Cardiff), Dr Stephen Lynch (Cardiff) and Dr Colin McGuinness (De Beers). Cardiff University and De Beers have previously worked closely together to understand unusual spectral signatures that were found in synthetic gemstones. This project will build on the legacy of this work. We are seeking a student to continue to develop a spectroscopic imaging experiment able to explore the luminescence behaviour of diamond under pulsed ultraviolet illumination over a range of timescales and temperatures. It is expected that the student will spend up to 6 weeks per year at De Beers research laboratories in Maidenhead validating their work. This PhD project thus provides an exciting opportunity to perform cutting-edge physics research that is also industrially relevant. While working at De Beers, the student will receive unique bespoke training and they will be able to experience the research and development environment in a multinational company.