NER: Molecular Electronics and Spintronics in Self-Assembled Monolayer Devices

该NER提案是在有机材料科学和化学（Burtman）;光学，光电子学和磁传输（Vardeny）以及器件物理（两者）方面具有不同专业知识的研究人员之间的合作努力。这两个合作PI已经合作了两年，并成功地建立了一个用于生长自组装单层（SAM）的装置。因此，我们在拟议研究的各个方面都有经验。 智力优势：该提案的目标是展示和研究电子和自旋电子学过程中的分子器件制成的SAM混合物的导电和绝缘分子与锚定硫醇端基，定制的运输过程与一维的隔离分子和聚集体与二维的运输。 SAM二极管将由具有两个锚定硫醇端基的分子线（1，4苯-二甲烷-硫醇，Me-BDT）和具有一个锚定硫醇端基的分子绝缘体（五硫醇，PT）的溶液混合物以金属铁磁（FM）和包括金和钴的非FM电极上的线/绝缘体的不同比率r制造。在r 10-3的Me-BDT分子应隔离在绝缘PT矩阵，而它们将形成二维（2D）的聚集体在r 0.1。我们建议检查（i）Me-BDT键合到相反的电极;（ii）Me-BDT分子表面密度，和（iii）Me-BDT分子聚集体的形成，使用从其他应用科学子领域借来的分子标签的滴定技术。这些测量包括光学吸收、振动光谱、AFM显微镜和电化学电荷计数。 使用所制造的SAM器件，我们将能够研究隔离和聚集的Me-BDT导电分子的电荷传输特性，从器件的I-V和微分电导特性，在不同的温度下测量。 此外，还将使用磁阻（MR）测量获得Me-BDT分子和聚集体的自旋输运性质，其中将研究Co基SAM器件的I-V特性作为外磁场的函数。从这些测量中，我们期望能够清楚地将基于隔离分子线的器件与基于2D分子线聚集体的器件分开;预期在一定的rc值处发生相变。 SAM生长所需的所有设备以及器件制造和测试的设置都已在我们的实验室中。我们已经获得了初步的结果，表明拟议的研究的可行性。 更广泛的影响：这些试点研究，如果成功的话，将显示一种替代的方法，研究电荷和自旋输运在单个分子，并在分子聚集体，显示电荷离域，使用SAM设备。我们的测量有可能使用可靠的测量技术大大提高分子电子场。此外，我们的实验工作，包括SAM增长，光学，磁光，器件制造，加工和测试的大型军火库的整合，将有助于有效地教育博士后助理，研究生和本科生谁将参与高度跨学科的研究项目。 该提案属于纳米器件和系统架构的子领域。

This NER proposal is a collaborative effort among researchers with diverse expertise in Organic Materials Science and Chemistry (Burtman); Optics, Optoelectronics, and Magneto-transport (Vardeny), and device Physics (both). The two co-PI.s have worked together for two years and have successfully built a set-up for growing self-assembled monolayers (SAM). We are therefore experienced in all aspects of the proposed studies. Intellectual Merit: The goal of this proposal is to demonstrate and study electronic and spintronics processes in molecular devices made of SAM mixtures of conducting and insulating molecules with anchoring thiol end groups, upon tailoring the transport process between isolated molecules with 1D-like transport and aggregates with 2D-like transport. SAM diodes will be fabricated from solution mixtures of molecular wires (1,4 benzene-dimethane-thiol, Me-BDT) with two anchoring thiol end groups, and molecular insulators (pentathiol, PT) with one anchoring thiol end group, at different ratio, r of wires/insulators on metallic ferromagnetic (FM) and non-FM electrodes that include gold and cobalt. At r 10-3 the Me-BDT molecules should be isolated in the insulating PT matrix, whereas they would form two-dimensional (2D) aggregates at r 0.1. We propose to check (i) the Me-BDT bonding to the opposite electrodes; (ii) Me-BDT molecular surface density, and (iii) Me-BDT molecular aggregate formation, using titration techniques of molecular tags that are borrowed from other Applied Science subfields. These measurements include optical absorption, vibrational spectroscopy, AFM microscopy, and electrochemical charge counting. Using the fabricated SAM devices we will be able to study the charge transport properties of isolated and aggregated Me-BDT conducting molecules from the device I-V and differential conductance characteristics, measured at different temperatures. In addition spin transport properties of Me-BDT molecules and aggregates will be also obtained using magnetoresistance (MR) measurements, where the I-V characteristic of Co-based SAM devices will be studied as a function of an external magnetic field. From these measurements we expect to be able to clearly separate devices based on isolated molecular wires from those based on 2D molecular wire aggregates; a phase transition at a certain rc value is anticipated. All the necessary equipment for the SAM growth and set-ups for the device fabrication and testing are already in our laboratory. We have obtained preliminary results that show the feasibility of the proposed studies. Broader Impact: These pilot research studies, if successful would show an alternative method of studying charge and spin transport in single molecules, and in molecular aggregates that show charge delocalization, using SAM devices. Our measurements have the potential to substantially advance the molecular electronic field using a reliable measurement technique. In addition the integration of our large arsenal of experimental efforts, including SAM growth, optics, magneto-optics, and device fabrication, processing and testing, will serve to efficiently educate the post-doctoral associate, and graduate and undergraduate students who will be involved in the highly interdisciplinary research projects. This proposal is in the subfield of Nanoscale Devices and System Architecture.