MRI: Development of a Sub-diffraction Limited Microscope for Imaging Ultrafast Dynamics from the Visible to Mid-infrared Spectral Range

该奖项由化学部的重大研究仪器、化学研究仪器计划、化学测量和成像计划以及材料研究部的重大研究仪器共同支持。得克萨斯大学奥斯汀分校的肖恩·罗伯茨教授和卡洛斯·贝兹教授以及德克萨斯农工大学的詹姆斯·巴特斯教授获得了这一奖项，他们正在开发一种亚衍射时间分辨超分辨率显微镜(TSM)。该仪器能够以接近10纳米的空间分辨率测量飞秒到毫秒时间尺度上展开的动力学。超分辨方法可以用来观察快速过程，如半导体纳米结构中的电子运动或生物膜的动态重组。TSM的设计是为了满足从近紫外到中红外的三个苛刻要求，即亚衍射空间分辨率、飞秒时间分辨率和光谱分辨率。这可以关键地使人们能够深入了解生物系统的内部工作原理，并创造出用于能量转换和量子信息科学的新材料。显微镜结构为与教职员工合作的学生研究人员提供培训。调试完成后，该仪器将通过集成到材料动力学与控制中心(CDCM)获得，该中心是位于奥斯汀的德克萨斯大学的材料研究科学与工程中心(MRSEC)。该项目为在研究中使用该仪器的研究生和博士后研究人员提供了发展超快科学和超分辨率显微镜背景的机会。TSM被配置为使用从近紫外光到中红外可调的激光脉冲来跟踪涉及电子、核和分子运动的动力学。集成原子力显微镜(AFM)允许原位绘制样品形貌图，并对尖端下方区域产生的信号进行近场尖端增强。利用显微镜进行的研究将由主要研究人员指导，研究低维半导体之间形成的结处的电子动力学，以及脂膜和聚合物混合物等非均质软物质中的结构波动。新的TSM仪器还将探索的其他研究方向包括太阳能材料中的能量和电荷迁移、van der Waals异质结构中的激子动力学、热电和中红外光子材料中的能量和声子传导、电池和智能窗中的离子迁移、细胞膜中的生物分子运动、光活性聚合物的非平衡动力学以及材料在强电场下的纳米控制。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This award is jointly supported by the Major Research Instrumentation, the Chemistry Research Instrumentation program, and the Chemical Measurement and Imaging program in the Division of Chemistry, and the Major Research Instrumentation in the Division of Materials Research. With this award, Professors Sean Roberts and Carlos Baiz at the University of Texas Austin and Professor James Batteas at Texas A&M University are developing a sub-diffraction Time-resolved Super-resolution Microscope (TSM). This instrument enables measurement of dynamics unfolding over femtosecond-to-millisecond timescales with spatial resolution approaching 10 nanometers. The super resolution approach can be used to view fast processes such as electron motion in semiconductor nanostructures or dynamic restructuring of biological membranes. The TSM is designed to achieve three demanding needs, sub-diffraction spatial resolution, femtosecond time resolution and spectral resolution, from the near-UV to mid-IR. This can critically enable key insights into the inner workings of biological systems and creation of new materials for energy conversion and quantum information science. The microscope construction provides training of student researchers who work with the faculty. After commissioning, the instrument is to be made available via its integration into the Center for Dynamics and Control of Materials (CDCM), a Materials Research Science and Engineering Center (MRSEC) based at the University of Texas at Austin. The project provides graduate students and postdoctoral researchers who use the instrument in their research the opportunity to develop a background in both ultrafast science and super-resolution microscopy.The TSM is configured to employ laser pulses tunable from the near-UV to mid-IR to follow dynamics involving electronic, nuclear, and molecular motions. An integrated atomic force microscope (AFM) allows in situ mapping of sample topography and near-field tip enhancement of signals produced in the region beneath the tip. The research enabled with the microscope will be directed by the principal investigators at studies of electronic dynamics at junctions formed between low-dimensional semiconductors and structural fluctuations within heterogeneous soft matter such as lipid membranes and polymer blends. Other research directions to be explored with the new TSM instrument include energy and charge migration in solar energy materials, exciton dynamics in van der Waals heterostructures, energy and phonon conduction in thermoelectric and mid-IR photonic materials, ion migration in batteries and smart windows, biomolecule motion in cell membranes, nonequilibrium dynamics of photoactive polymers, and nanoscopic control of materials under intense electric fields.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.