Tip-based Femtosecond Multiphoton Spectroscopy with Radiative Heating

One of grand challenges in nanoscience and nanotechnology is to achieve fundamental under- standing of the dynamic evolution of materials in actual operating environment, non-equilibrium conditions, or undergoing chemical reactions at the nanoscale. This requires forefront advances in imaging and analysis techniques that combine nanometer-scale spatial resolution, optical excitation and spectroscopic detection for direct in-situ observation of the fundamental processes. The proposed innovation is in-situ nanoscale imaging method by integrating tip-based near-field scanning optical microscopy with femtosecond multiphoton spectroscopy, and by expanding its operational temperature beyond conventional range by laser heating. Phase I project proved the operation of tip-based near-field scanning optical microscopy up to 400°C with high spatial resolution. When applied to the study of ferroelectric materials, the pro- posed method produced a wealth of information to elucidate the characteristics of these materials at high temperatures. In this Phase II project, the proposed innovation will be taken to the next level, from a benchtop laboratory setup to a commercial prototype ready for customer evaluation. Several key technologies will be developed to enable the operation in harsh environment, including thermal stabilization system and high temperature scanning probes to further increase the temperature range up to 1000°C. A couple of in-operando nanoscale materials characterization experiments will be performed to validate the performance of prototype. Commercial Applications and Other Benefits: The outcome of this project is the development of a unique but flexible nanoscale imaging instrument that will be widely adopted in scientific research from biomedicine to materials science. This nanoimaging tool can be further applied to develop a broad range of technical applications, including high-efficiency solar cells and to understand the behavior of materials at extreme operating conditions. The entirely new capability of in-situ nanoscale spectral imaging will have a profound impact to many fields of science, engineering and manufacturing.