RAISE-TAQS: Quantum-based chemical sensing

这个项目的目标是探索化学传感和分析的新方法。这种方法基于电子的量子力学特性，即自旋。金刚石样品中含有一种特殊的缺陷，氮空位（NV）中心。金刚石中的一个碳原子被一个空位附近的氮原子所取代。这样的样品发光的方式会被附近分子的自旋所改变。在这个项目中，化学家、物理学家和电气工程师正在合作制作钻石样品，在钻石表面下的特定位置放置NV中心阵列。然后，他们研究了NV中心发出的光是如何依赖于钻石样品外部分子的位置和距离的。由于基于自旋的化学传感器目前还不存在，这项工作有可能导致具有非常高灵敏度的新型化学传感器，可能在单分子水平上。如果成功，基于自旋的化学传感器将在广泛的化学、环境和生物医学应用中发挥作用。除了培养量子科学方面的研究生和本科生外，研究团队还参与了有关量子化学检测的外展活动和公众友好播客的开发。该研究的目标是通过利用金刚石中NV中心独特的量子力学特性，探索探测和测量分子结合、解理和表面动态运动的新方法。新的传感方法是基于表征NV中心的电子自旋如何与位于金刚石-水界面附近的分子中的自旋相互作用。纳米光刻图像化和离子注入方法被用于制备含有NV中心阵列的样品，每个NV中心都可以单独探测和操作。纳米光子方法被用于提供从单个NV中心到光学探测器的光耦合的有效途径。金刚石表面被分子功能化，分子中含有定义良好的自旋探针，这些自旋探针与亚表面NV中心的相互作用取决于自旋探针与NV中心之间的接近程度。研究人员正在利用分子自旋和NV中心自旋之间的相互作用，作为一种潜在的化学传感新方法，通过NV中心的光谱变化来报告分子从表面的结合或释放。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The goal of this project is to explore novel approaches to chemical sensing and analysis. This approach based on a quantum-mechanical property of electrons known as spin. Diamond samples containing a special defect, the nitrogen vacancy (NV) center. One of the carbon atoms in the diamond is replaced by a nitrogen atom adjacent to a vacancy. Such samples emit light in a way that is altered by the presence of spins on nearby molecules. In this project, chemists, physicists, and electrical engineers are collaborating to make diamond samples with arrays of NV centers placed at very specific locations beneath diamond surfaces. They then investigate how the light emitted by the NV centers depends on the location and distance of molecules located immediately outside of the diamond sample. Because spin-based chemical sensors do not currently exist, this work has the potential to lead to new types of chemical sensors with very high sensitivity, possibly at the single-molecule level. If successful, spin-based chemical sensors would be useful in a wide range of chemical, environmental and biomedical applications. In addition to training graduate and undergraduate students in the quantum-based science, the researcher team is also engaged with outreach events and development of public-friendly podcast on quantum-based chemical detection.The goal of the research is to explore fundamentally new approaches to detecting and measuringmolecular binding, cleavage, and dynamical motions at surfaces by exploiting the unique quantum mechanical properties of NV centers in diamond. The new sensing approach is based on characterizinghow electron spins of NV centers interact with spins present in molecules located nearby at the diamond-water interface. Nanolithographic patterning and ion implantation methods are being used to prepare samples containing arrays of NV centers, each of which can be probed and manipulated individually. Nanophotonic methods are being used to provide efficient ways of optically coupling light from individual NV centers to optical detectors. The diamond surfaces are being functionalized with molecules containing well defined spin probes that interact with the sub-surface NV centers in a manner that depends on the proximity between the spin probe and the NV centers. Researchers are using the resulting interactions between the spin of the molecules and the spin of the NV centers as a potentially novel approach to chemical sensing in which binding or release of molecules from surfaces is reported via spectroscopic changes in the NV centers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.