MRI-R2: Development of a Low Temperature Single Spin Tunneling Force Microscope

MRI-R2：低温单自旋隧道力显微镜的开发

• 批准号: 0959328
• 负责人: Clayton Williams
• 金额: $ 56.31万
• 依托单位: University of Utah
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-03-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0959328&HistoricalAwards=false
• 关键词: MRI; R2; Development; Low; Temperature

0959328WilliamsU. of UtahMRI: Development of a Low Temperature Single Spin Tunneling Force MicroscopeTechnical Summary: This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). A recent advance in Scanning Probe Microscopy has made it possible to image individual electron trap states in dielectric surfaces with atomic scale spatial resolution. In this method, a single electron is induced to tunnel between a scanning probe tip and an electronic state at the surface. Each individual electron tunneling event is detected by electrostatic force. This project aims to expand this exciting new capability to the detection and manipulation of single electron spins. A liquid helium temperature Single Spin Tunneling Force Microscope will be developed, capable of performing single spin Electron Spin Resonance (ESR) measurements and single spin manipulation. The instrument will consist of a low temperature Atomic Force Microscope, modified for force detection of spin-dependent single electron tunneling events with ESR excitation. The proposed instrument represents an entirely new approach to atomic scale single spin detection. It is based on the utilization of spin-selection rules, in contrast to previous approaches based on the detection of weak magnetic force detection. The instrument will enable chemical/physical identification (g-factor, energy, wavefunction imaging) of individual paramagnetic states, such as point defects found in dielectric and semiconductor materials, with atomic scale spatial resolution. It will also provide a means to study atomic scale magnetic fields and spin relaxation processes and will open a way to read out individual nuclear spins that are hyperfine coupled to adjacent electron spins. The project will train undergraduate and graduate students (emphasis on underrepresented groups) in state of the art atomic scale measurement techniques, and open up new collaborations with research groups within and outside the University of Utah.Layman Summary: This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Spin is a fundamental property of electrons and some nuclei, which causes them to act like tiny bar magnets. Techniques allowing the observation of spins have had a profound impact in the past. The most prominent examples are based upon magnetic resonance, which is employed in medical diagnostics and analytical methods for chemistry and materials science. Most of these techniques detect many billions of spins. A few previous experiments conducted on very selective spin systems have demonstrated single spin detection. Most of these however could not resolve the spatial location of the spins very well, while others required extremely low temperatures. The proposed project aims to develop a new microscope which is able to detect individual electron spins with atomic scale precision over a range of temperatures. This instrument is called the Single Spin Tunneling Force Microscope. It is based on the quantum mechanical tunneling effect, a phenomena that allows electrons trapped in one region to traverse an impenetrable barrier and reappear on the other side. Tunneling of single electrons has already been observed with force microscopy. Tunneling can be influenced by electron spin. In the proposed instrument, spins are detected using the principle of spin dependent tunneling. The development of the proposed microscope could lead to dramatic progress in many research fields. The ability to observe individual spins in many materials and molecular systems could lead to breakthroughs for future spintronic devices. It could also significantly contribute to the development of quantum computers and help to understand atomic scale defects which influence conventional electronic materials and devices. The study of these defect spins can lead to insights into strategies for improvements in solar cells, semiconductor lighting devices, displays and computer applications.

0959328威廉姆斯。技术综述：该奖项是根据2009年美国复苏和再投资法案(Public Law Of 2009)(公共法律111-5)资助的。扫描探针显微镜的最新进展使以原子尺度的空间分辨率成像电介质表面的单个电子陷阱态成为可能。在这种方法中，单个电子被诱导在扫描探针尖端和表面的电子态之间隧道。每个单独的电子隧穿事件都是由静电力探测到的。该项目旨在将这一令人兴奋的新能力扩展到单电子自旋的探测和操纵。液氦温度单自旋隧道力显微镜将被开发，能够进行单自旋电子自旋共振(ESR)测量和单自旋操纵。该仪器将由一个低温原子力显微镜组成，经过改装后可以用ESR激发对自旋相关的单电子隧穿事件进行力检测。该仪器代表了一种全新的原子尺度单自旋探测方法。它基于自旋选择规则的利用，而不是以往基于弱磁力检测的方法。该仪器将能够以原子尺度的空间分辨率对单个顺磁状态进行化学/物理识别(g因子、能量、波函数成像)，例如在介电材料和半导体材料中发现的点缺陷。它还将提供一种研究原子尺度磁场和自旋弛豫过程的方法，并将打开一种读出与相邻电子自旋超精细耦合的单个核自旋的方法。该项目将培训本科生和研究生(重点是未被充分代表的群体)掌握最先进的原子尺度测量技术，并与犹他州大学内外的研究小组展开新的合作。莱曼摘要：该奖项由2009年美国复苏和再投资法案(公共法律111-5)资助。自旋是电子和一些原子核的基本性质，这使它们的行为像微小的条形磁铁。过去，观测自转的技术产生了深远的影响。最突出的例子是磁共振，它被用于医学诊断以及化学和材料科学的分析方法。这些技术中的大多数都能探测到数十亿次自转。之前在非常选择性的自旋系统上进行的几个实验已经证明了单自旋探测。然而，其中大多数不能很好地解决自旋的空间位置，而另一些则需要极低的温度。拟议中的项目旨在开发一种新的显微镜，它能够在一定温度范围内以原子尺度的精度检测单个电子自旋。这种仪器被称为单自旋隧道力显微镜。它基于量子力学隧道效应，这种现象允许被困在一个区域的电子穿过无法穿透的势垒，并在另一边重新出现。单电子的隧穿已经用力显微镜观察到了。电子自旋可以影响隧道效应。在所提出的仪器中，利用自旋相关隧穿原理来检测自旋。提出的显微镜的发展可能会在许多研究领域带来巨大的进步。在许多材料和分子系统中观察单个自旋的能力可能会为未来的自旋电子设备带来突破。它还可以对量子计算机的发展做出重大贡献，并有助于理解影响传统电子材料和器件的原子尺度缺陷。对这些缺陷自旋的研究可以引导人们深入了解太阳能电池、半导体照明设备、显示器和计算机应用的改进策略。