Visualizing the electronic structure of thin layers of Bi₂Sr₂CaCu₂O_8+delta

The role of dimensionality in high Tc superconductivity is an interesting issue: after all, many of the high Tc superconductor have layered atomic structures, and yet the link between the high Tc superconductivity and the two-dimensional nature of the crystal structure remains elusive. Here, we fabricate few-layer Bi₂Sr₂CaCu₂O_8+delta samples, and use scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) to investigate the electronic structure, such as superconducting gap, pseudo gap and charge order, in Bi₂Sr₂CaCu₂O_8+delta in the 2D limit.