AVS 62nd International Symposium & Exhibition
    Scanning Probe Microscopy Focus Topic Wednesday Sessions
       Session SP+2D+AS+NS+SS-WeA

Invited Paper SP+2D+AS+NS+SS-WeA1
Geometric and Electronic Structures of Epitaxially Grown Pnictide 122, 111 and CuxBi2Se3 Samples

Wednesday, October 21, 2015, 2:20 pm, Room 212A

Session: Probing Electronic and Transport Properties
Presenter: Young Kuk, Seoul National University, Republic of Korea
Correspondent: Click to Email
Order parameters were measured mainly on low-temperature cleaved, superconductor surfaces from their measured topographic images (constant current maps) and Fourier-transformed, measured density of states (energy dependent dI/dV map) in previous scanning tunneling microscopy (STM) studies. However, no direct evidence of coupling mechanisms has been given for these high temperature superconductors by these STM studies. We intend to study how homogeneity of a doped sample influences the superconducting property in an STM study. We were able to grow pnictide 111, 122, and CuxBi2Se3 samples by molecular beam epitaxy. We found that surfaces of these grown samples are often terminated by alkali or alkaline atomic plane or non-superconducting metallic planes. These surfaces reveal distorted superconducting or non-superconducting properties. We adopted various ways to expose the superconducting planes in these samples. At the same time, we tried to grow samples homogeneously doped over the coherence lengths. Nodal structures were observed on these samples in their quasiparticle interference patterns. In this talk we will discuss the properties of the s±, s, d states as likely candidates pairing states for these materials.