Electronic Properties of Thin Film Organic Superconductors Studied Using Synchrotron Radiation-Based Soft X-Ray Spectroscopies

Trustees Of Boston University, Boston

Investigators

Abstract

The project aims to synthesize thin films of organic superconductors and to study their electronic properties using a powerful combination of high resolution synchrotron radiation-based soft x-ray spectroscopies. A major goal is to solve the beam damage and surface problems associated with earlier studies of single crystals by growing thin films of these materials in-situ, and continuously translating the films in front of the synchrotron radiation beam as spectra are recorded. Organic molecular beam deposition methods will be developed for the in-situ synthesis of ordered thin films of organic superconductors. Definitive measurements will be made of the density of states, band structure, Fermi surfaces, and orbital bonding of thin film organic superconductors. This project will have a significant impact on the education of students and postdoctoral research associates by exposing them to a highly collaborative research environment at national user facilities. They will be educated in the chemistry and physics of novel organic materials, and in the application of synchrotron radiation spectroscopies in their study. This is an ambitious program that aims to produce definitive measurements of surface and bulk electronic structure of organic superconductors. %%% Superconductors are fascinating materials that, under appropriate conditions, can carry an electrical current with no resistance. While most superconductors are inorganic materials such as metals, there are some that are organic, i.e., carbon-based. These organic superconductors are complex materials whose properties are not well understood. Thin films of organic superconductors have not been routinely synthesized, and this will be a major challenge. The basic electronic properties of these materials will be studied using two probes: photoemission spectroscopy and x-ray emission spectroscopy. These probes involve the excitation of the electrons in the material by illumination with intense x-rays and measuring their response. This combination of spectroscopies will provide a comprehensive understanding of the electronic and chemical properties of these complex materials. This program will also educate postdoctoral research associates, graduate and undergraduate students in the physics and chemistry of organic superconductors, and the application of state of the art spectroscopic probes in their study. This class of electronic materials is of high interest to industry, and students trained in these areas will be very competitive in the job market.