Electron Kaleidoscope

You are probably aware the Michael and I are doing some work on artificial graphene, a man-made material that mimics the electronic properties of real graphene - the material and our research project are explained in more detail in this blog post. In a nutshell, the system confines electrons to a hexagonally shaped "flake" with a lattice of so-called scatterers, that is, a lattice of small circular areas that are "forbidden" for the electrons.

I recently made plots of the electronic density (that is, the probability to find an electron at a certain point in the flake) for different eigenstates of the electronic wave functions. I found those plots so nice - from an artistic view point as well as a scientific one - that I thought I'd want to share them with you.

A short explanation for the scientifically minded readers: white means very high electron density, the color scale for decreasing density goes via orange and blueish colors to black, which means no electrons. The color scale is logarithmic, because I was not so much interested in the density as such, but the areas where the density is zero - these areas are called the "nodes" of the wave functions.

The symmetry of these nodes is dictated by a competition between the hexagonal symmetry of the outer confinement and the symmetry of the lattice of scatterers (the wave function is forced to be zero there). This competition (physicists call such a system a "frustrated system") results in the Kaleidoskope-like structure of the the density of electrons in that material.