Scanning Probe and Point Projection Microscopies for Fundamental Nano-Science Studies

扫描探针显微镜（SPMs）已经非常有效的工具，阐明固有的性质，以纳米尺度。SPMs的进一步开发和应用是我们整个研究计划的核心。我们提出的研究将进一步获得对硅的表面限制纳米级性质的基本理解。像场控制计算（FCC）这样的概念，是极快和低功耗经典计算的基础，已经被我们的发现所改变，硅悬空键（db），通过从H端硅表面去除单个H原子而产生，作为原子硅量子点。以前的实现需要极端低温条件。耦合db使FCC在室温下可行。耦合db的主题还处于起步阶段。作为概念的先驱，由于我们的设施，大量的重新加工，以及以前的工作和合作，我们处于探索它的理想位置。我们新建立的高度稳定的4开尔文SPM（扫描隧道显微镜，STM和原子力显微镜，AFM）使我们进入了一个新的制造和测量体系。整体场离子显微镜允许常规部署我们的氮稳定单原子尖端作为扫描探针。第二个4 K仪器，具有磁铁和射频检测能力，将很快投入使用，允许最理想的单自旋电子自旋共振测量。单db和耦合db的光谱学将为经典和量子计算研究提供信息。库仑阻塞效应将变得可访问。AFM力扫描将提供一个新的视角来研究DBs的电荷分布。我们开发的非凡的新型原子力显微镜传感器提高了我们成功的机会。通过电流-电压、IV、光谱对DB间隧道的实验研究，以及与合作者建立的紧密耦合模型，将得到相互作用强度（预计在2 nm分离时约为100 meV），这对DB集成的信息传输模型至关重要。DB耦合强度的知识将指导与卡尔加里的Barry Sanders进行广泛的联合理论和实验计划，以评估隧道速率和相干特性。我们预测~10e5相干振荡可以在退相干事件之前完成。我们将与麦吉尔大学的Hong Guo合作，并与一名共同指导的学生一起，扩展我们对表面态介导转运的联合研究。我们的目标是揭示这种表面运输通道的性质和规模，从而解决一些争议，并进一步期望表明以这种独特的方式连接未来纳米器件的可能性。我们自制的多探针STM将使这些原子尺度的输运研究成为可能。将探索基于db的导线、隧道间隙和空前均匀的单电子晶体管。与UBC的Konrad Walus合作，他与量子退火计算机制造商dWAVE合作，我们有一个独特的FCC电路优化研究计划。贯穿整个提案的是我们的纳米尖端的改进和应用。尖端是由化学和场辅助，空间限制蚀刻，留下所有的顶端W原子氮化涂层。与无涂层的尖锐金属尖不同，我们的尖非常坚固。与以往任何光源的相干电子发射开角~3度相比，相干电子发射开角达到了bbbb14度。我们计算出0.2 nm全息投影显微镜的分辨率现在是可能的，而以前是1.5 nm。高分辨率和低光束损伤将使生物分子成像。纳米磁铁周围的相变将会变得容易。我们的训练记录非常好。我们的学生将获得并创造与这项工作直接相关的工作。

Scanning probe microscopes (SPMs) have been extraordinarily effective tools for elucidating properties inherent to the nano-scale. Further development and application of SPMs is central to our overall research program. Our proposed studies will gain further fundamental understanding of surface-confined nano-scale properties of silicon. Concepts like field controlled computing, FCC, a basis for extremely fast and low power classical computing have been transformed by our discovery that silicon dangling bonds (DBs), created by removal of single H atoms from an H-terminated silicon surface, serve as atomic silicon quantum dots. Previous implementations required extreme cryogenic conditions. Coupled DBs make FCC viable at room temperature. The subject of coupled DBs is in its infancy. As pioneers of the concept and due to our facilities, substantial re-tooling, and previous work and collaborations, we are ideally positioned to explore it. Our newly established and highly stable 4 Kelvin SPM (both scanning tunneling microscope, STM, and atomic force microscope, AFM) allows us to enter a new fabrication and measurement regime. An integral field ion microscope allows routine deployment of our nitrogen stabilized single atom tip as a scanned probe. A second 4 K instrument, with magnet, and radio frequency detection capabilities will soon be operational, allowing most ideal ever single spin electron spin resonance measurements. The spectroscopy of single and coupled DBs will inform classical and quantum computing studies. Coulomb blockading effects will become accessible. AFM force scans will provide a new perspective on charge distributions at DBs. Extraordinary new AFM sensors we have developed enhance our chances of success. Experimental study of inter-DB tunneling through current-voltage, IV, spectra, with close coupled models developed with collaborators, will yield strength of interaction (~100 meV at 2 nm separation is expected) critically informing models of information conveyance by DB ensembles. Knowledge of DB coupling strength will guide an extensive joint theoretical and experimental program with Barry Sanders at Calgary that will assess tunnel rate and coherence properties. We predict ~10e5 coherent oscillations may be completed before a decohering event. In collaboration with Hong Guo at McGill, and with a co-supervised student, we will extend our joint studies of surface state mediated transport. We aim to reveal the nature and magnitude of such surface transport channels, thereby settling some controversy, and furthermore expect to indicate the possibility of connecting future nano-devices in this unique way. Our home made multi-probe STM will enable these atom-scale transport studies. DB-based wires, tunnel gaps and single electron transistors of unprecedented uniformity will be explored. With Konrad Walus of UBC, who works with dWAVE, the maker of a quantum annealing computer, we have a unique program of study for FCC circuit optimization.Woven throughout the proposal are refinements and applications of our nano-tips. The tip is fabricated by a chemical and field assisted, spatially restricted etch that leaves all but the apex W atom nitride coated. Unlike coating-free sharp metal tips, ours are extremely robust. A coherent electron emission opening angle of >14 degrees has been achieved, compared to ~3 degrees for any previous source. We calculate that 0.2 nm holographic projection microscope resolution is now possible, compared to 1.5 nm previously. High resolution and low beam damage will allow biological molecules to be imaged. Phase change around nano-magnets will be accessible. Our training record is excellent. Our students will get and will create jobs directly related to this work.