Abstract: For strongly correlated systems, there are many competing low energy states. It is particularly challenging for numerical approaches.  Recently we have modified the numerical methods to treat the spatially inhomogeneous states like stripes in the t-J model. They are shown to be related to the collective excitations of the model. The introduction of a weak electron- phonon interaction to renormalize the effective hopping constant can stabilize the stripe ground states with the right periods reported by experiments. The results are shown to agree very well with experiments. Since the renormalization will depend on local charge density, thus the variational calculation has to use an iterative approach with multivariable minimization. We will discuss the method and results in this talk. In addition, a generalization of the Gutzwiller projected variational wave function to treat varying number of particles will be discussed also. 

 

About the Speaker: Prof. Ting-Kuo Lee is a Distinguished Research Fellow and the Director of Institute of Physics of the Academia Sinica in Taiwan. He got his degrees in Physics at the National Taiwan University (BS) and Brown University (PhD) and postdoctoral training at University of California in Santa Barbara and City College of City University of New York. From 1982 till 1997, Ting-Kuo Lee was Faculty of Physics at Virginia Polytechnic Institute and State University. His research interests are in areas of strongly correlated electron physics, high temperature superconductivity, thermal electric materials, and computational physics and optimization methods, 3D image reconstruction for x-ray diffraction microscopy.

 

Date&Time: August 7, 2013 (Wednesday), 16:30 - 17:30
Location: 606 Conference Room