Florida State University

Title: Charge density waves in 2D electrons: Wigner crystals, bubbles, and stripes .



Abstract: Two-dimensional electrons systems subjected to perpendicular magnetic fields (B) exhibit single particle and many body effects---most notably the integer and fractional quantum Hall effects. However, in clean 2DES at moderate B, corresponding to Landau levels filling factors > 4, theory predicts the formation of isotropic crystal states with two or more electrons per lattice site (Bubbles) and anisotropic stripe states. Our microwave conduction measurements have recently provided evidence for Bubbles and also the rf signature of the anisotropic stripe phase. I will discuss these and other measurements in the context of what we know about clean 2D electrons in high Landau levels.