AVS 56th International Symposium & Exhibition
    Magnetic Interfaces and Nanostructures Wednesday Sessions
       Session MI+EM-WeA

Paper MI+EM-WeA8
Magnetic Molecules on GaN: A Low Temperature STM Investigation

Wednesday, November 11, 2009, 4:20 pm, Room C1

Session: Magnetism and Spin Injection in Semiconductors
Presenter: K. Clark, Ohio University
Authors: K. Clark, Ohio University
D. Acharya, Ohio University
V. Iancu, Ohio University
E. Lu, Ohio University
A. Smith, Ohio University
S.-W. Hla, Ohio University
Correspondent: Click to Email
Spin electron interactions involving magnetic molecules and semiconductor surfaces are of great interest for the development of molecular spintronic devices. Due to its wide range of applications, GaN (0001) surface has received a special attention for the development of novel electronic devices. Here, we studied electronic and structural properties of TBrPP-Co molecules deposited on a freshly grown nitrogen polar GaN (0001) surface using a scanning tunneling microscopy and spectroscopy at 4.6 K under an ultra-high-vacuum condition. The TBrPP-Co molecule has a spin-active cobalt atom caged at the center of porphyrin unit and four bromo-phenyl groups are attached to its four corners. On GaN(0001), the molecules bind the surface via two molecular conformations: saddle and planar. In saddle conformation, the central part of the molecule is bent by lifting the two pyrrole units of the porphyrin macrocycle. STM images shows various self-assembled clusters of molecules on GaN(0001) surface. Within the self-assembled molecular clusters, the molecules are aligned either parallel or 90 degree rotated to each other. In the presentation, we will discuss the spin-electron coupling of this molecule-surface system. This work is supported by the Ohio University BNNT, NSF-PIRE: OISE 0730257, NSF-EMT: CCF-0622158, and the United States Department of Energy, DE-FG02-02ER46012 grants.