POWRE: Understanding the Electronic and Optical Properties of Conducting Polymers through Quantum Monte Carlo Simulations

本项目利用量子蒙特卡罗模拟技术研究导电聚合物的电学和光学性质。大的非线性光学响应和亚皮秒级别的超快响应使某些聚合物结构成为快速开关和存储器件的极佳候选者。方法是研究库仑相互作用、量子晶格涨落和无序对局域化性质的影响。这些结果有望解决不同实验群体的非线性光学极化率测量值的差异，特别是磁化率谱中令人费解的双光子峰的存在。此外，尽管结构对称性被破坏，但表现出与天然形式相当的大电导率的聚苯胺衍生物将被模拟。模拟将作为库仑相互作用强度、无序、离子质量和掺杂剂浓度的函数进行。%这是根据妇女研究和教育职业机会(POWRE)计划提供的研究增强补助金。这项研究将有助于了解和利用聚合物在电子/光子应用中的基础材料科学知识。该跨学科项目涉及物理和化学领域的理论和实验之间的合作，并强调通过将研究生的参与纳入与课堂活动相关的研究，从而将研究和教育结合起来。该项目由材料研究司和MPS OMA(多学科活动办公室)共同支持。***

This project investigates the electronic and optical properties of conducting polymers using quantum Monte Carlo simulation techniques. The large nonlinear optical response and ultrafast response at the sub-picosecond level make certain polymer structures excellent candidates for fast switching and memory devices. The approach is to study the influence of Coulomb interactions, quantum lattice fluctuations, and disorder on and localization properties. The results are expected to resolve discrepancies in the measured values of nonlinear optical susceptibility by various experimental groups, particularly the puzzling presence of a two photon peak in the susceptibility spectrum. In addition, polyaniline derivatives, which exhibit large conductivities comparable to the native form, despite the broken structural symmetry will be modeled. Simulations will be carried out as a function of the strength of Coulomb interaction, disorder, ionic mass and dopant concentration.%%% This is a research enhancement grant made under the Professional Opportunities for Women in Research and Education (POWRE) program. The research will contribute basic materials science knowledge relevant to the understanding and utilization of polymers in electronic/photonic applications. The interdisciplinary project involves collaborations among theory and experiment across physics and chemistry, and also places emphasis on the integration of research and education by incorporating graduate student participation into research related to classroom activities. The project is co-supported by the Division of Materials Research, and the MPS OMA(Office of Multidisciplinary Activities). ***