SGER: Fractal Surface Enhanced Chemical & Biological Sensors

这是一项探索性研究小额资助（SGER）奖。这是对“下一代化学和生物传感器和传感系统”亲爱的同事信的回应，NSF-02-112。在本项目中，将制造新型的纳米结构分形和分形微腔传感器。这些传感器有望在微量分子的光学检测中提供无与伦比的灵敏度，包括少量的生物和化学试剂。该传感器基于分形金属-介电复合材料，可以支持多种等离子体模式，从而大大增强了光学响应。分形材料中的等离子体模式经历局域化，使得电磁能量在纳米尺度的“热点”区域积累和集中，从而导致局部场的强烈增强。谐振区即热点可以作为不同谐振频率的纳米天线。将等离子体纳米谐振腔中局部光激发的能量集中效应与基于介电腔的微谐振腔相结合，可以实现光学现象的高强度增强。这项研究可能会导致具有无与伦比的灵敏度的新型光学传感器。拟议的研究由普渡大学传感科学与技术中心的协同活动支持，将传感器科学与技术的前沿研究与一流的教育和培训相结合。这是一项探索性研究小额资助（SGER）奖。这是对“下一代化学和生物传感器和传感系统”亲爱的同事信的回应，NSF-02-112。在本项目中，将制造新型的纳米结构分形和分形微腔传感器。这些传感器有望在微量分子的光学检测中提供无与伦比的灵敏度，包括少量的生物和化学试剂。该传感器基于分形金属-介电复合材料，可以支持多种等离子体模式，从而大大增强了光学响应。等离子体代表了金属和金属-介电复合材料中电子的集体振荡，它们被认为是表面增强光谱的主要原因，在表面增强光谱中，等离子体纳米结构导致光学光谱灵敏度的许多数量级增加。分形材料中的等离子体模式经历局域化，使得电磁能量在纳米尺度的“热点”区域积累和集中，从而导致局部场的强烈增强。将等离子体分形模式中局部光激发的能量集中效应与基于介电腔的微谐振器相结合，可以实现创纪录的光学现象增强。这项研究最终可以开发出具有无与伦比灵敏度的新型光学传感器。该研究得到了普渡大学传感科学与技术中心协同活动的支持，将传感器科学与技术的前沿研究与一流的教育和培训相结合。

This is a Small Grants for Exploratory Research (SGER) award. It is in response to the "Next Generation Chemical and Biological Sensors and Sensing Systems" Dear Colleague letter, NSF-02-112. In this project, novel nanostructured fractal and fractal-microcavity sensors will be fabricated. These sensors are expected to provide unsurpassed sensitivity in optical detection of molecules in minute quantities, including small amounts of biological and chemical agents. The sensors are based on fractal metal-dielectric composites, which can support various plasmon modes resulting in giant enhancement of optical responses. Plasmon modes in fractal materials experience localization so that the electromagnetic energy is accumulated and concentrated in nanometer-scale areas, "hot spots," leading to the strongly enhanced local fields. The resonating areas, hot spots, can act as nano-antennas with different resonance frequencies. Combining the energy-concentrating effects from localized optical excitations in plasmonic nano-resonators with micro-resonators based on dielectric cavities, can result in record-high enhancement of optical phenomena. This research could lead to new optical sensors with unsurpassed sensitivity. The proposed research, supported by synergistic activities with Center for Sensing Science and Technology at Purdue will integrate cutting-edge research in sensor science and technology with top-flight education and training. This is a Small Grants for Exploratory Research (SGER) award. It is in response to the "Next Generation Chemical and Biological Sensors and Sensing Systems" Dear Colleague letter, NSF-02-112. In this project, novel nanostructured fractal and fractal-microcavity sensors will be fabricated. These sensors are expected to provide unsurpassed sensitivity in optical detection of molecules in minute quantities, including small amounts of biological and chemical agents. The sensors are based on fractal metal-dielectric composites, which can support various plasmon modes resulting in giant enhancement of optical responses. Plasmons represent collective oscillations of electrons in metals and metal-dielectric composites and they are known to be a major reason for surface-enhanced spectroscopy, in which plasmonic nanostructures lead to many orders of magnitude increases in the sensitivities of optical spectroscopies. Plasmon modes in fractal materials experience localization so that the electromagnetic energy is accumulated and concentrated in nanometer-scale areas, "hot spots," leading to the strongly enhanced local fields. Combining the energy-concentrating effects from localized optical excitations in plasmonic fractal modes with micro-resonators based on dielectric cavities can result in record-high enhancement of optical phenomena. This research can eventually lead to developing new optical sensors with unsurpassed sensitivity. The research, supported by synergistic activities with the Center for Sensing Science and Technology at Purdue will integrate cutting-edge research in sensor science and technology with top-flight education and training.