- 0 Spatial variation of magnitude of the pseudogap in Ca2-xNaxCuO2Cl2 (x = 0.08). The pseudogap is observed in green and yellow areas while not in purple areas. The spatial variation exhibits two-fold symmetry and locally breaks four-fold symmetry of the crystalline lattice. See also Y. Kohsaka et al., "Visualization of the emergence of the pseudogap state and the evolution to superconductivity in a lightly hole-doped Mott insulator", Nature Physics (Advanced Online Publication) (2012). ©Yuhki Kousaka
- 1 A picture depicting that localized unidirectional electronic structures and itinerant Cooper pairs of copper-oxides high-temperature superconductors coexist in real space. This image was used in Physics World (April 2011 issue). See also Y. Kohsaka et al., "How Cooper pairs vanish approaching the Mott insulator in Bi2Sr2CaCu2O8+δ", Nature 454, 1072 (2008). ©Yuhki Kousaka, RIKEN and Cornell University
- 2 (bottom) An STM image of Ca2-xNaxCuO2Cl2 (x = 0.12). (top) An image of the tunneling current ratio at a positive and a negative bias voltages, simultaneously taken with the STM image. This image, reflecting spatial variations of the local density-of-states, reveals unidirectional electronic structures breaking the symmetry of crystalline lattice. This image appeared on the cover of Science (9 March 2007). Click the image and a movie is shown. See also Y. Kohsaka et al., "An Intrinsic Bond-Centered Electronic Glass with Unidirectional Domains in Underdoped Cuprates", Science 315, 1380 (2007). ©AAAS
- 3 (back) STM images. (front) Images of the tunneling current ratio at a positive and a negative bias voltages, simultaneously taken with the STM images. These images reflect spatial variations of the local density-of-states. (left) Ca2-xNaxCuO2Cl2. (right) Bi2Sr2CaCu2Oy. Whereas these STM images are different due to the difference of crystal structures, the spatial variations of the local density-of-states commonly show unidirectional electronic structures. This evidently indicates that the unidirectional electronic structures are intrinsic to the CuO2 planes. See also Y. Kohsaka et al., "An Intrinsic Bond-Centered Electronic Glass with Unidirectional Domains in Underdoped Cuprates", Science 315, 1380 (2007). ©Yuhki Kohsaka
- 4 A close-up image of unidirectional electronic structures in Ca2-xNaxCuO2Cl2. Click the image and the simultaneous STM images is shown. Local maxima and minima of the electronic structures are located between atoms of the STM image, or at the oxygen site of the CuO2 planes. This image was used in a monthly science magazine issued in France, Sciece & Vie (N°1106 novembre 2009). See also Y. Kohsaka et al., "An Intrinsic Bond-Centered Electronic Glass with Unidirectional Domains in Underdoped Cuprates", Science 315, 1380 (2007). ©Yuhki Kohsaka
- last updated: 2012-05-21
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