The Reflection Spectra of the Bechgaard Salts: a Theoretical Determination

The aim of this contribution is to analyze to some extent the reflectivity of family of organic salts known as the Bechgaard salts. The reflectivity will be calculated using a well known theoretical framework. Since this calculation demands as input data the electrical conductivity and the susceptibility, existing results for these quantities were used. The main motivation for this calculation was to attempt to "tie up" the reflectivity with various parameters of the Bechgaard salts in the Hubbard model. As these materials are quasi-one-dimensional, it is hoped to extend in the future the results of this contribution to systems of higher dimensionality. Details of the calculation leading to an expression for the reflectivity will be discussed. It is nonlinear, and shows the dependence of the reflectivity on various material parameters (within the Hubbard model), such as the transfer integral or the band filling. The position of the region where the reflectivity tends to zero will also be estimated as a function of the model parameters. Finally, some possibilities of extension of the results obtained to 2D systems are briefly mentioned.