Download Kondo physics in single-molecule transistors

Kondo physics in single-molecule transistors
D. Natelsona , L.H. Yub , Z.K. Keaneb , J.W. Ciszekc , L. Chengc , M.P. Stewartc , M. Fabiand , G. Palmerd,
and J.M. Tourc
a
Department of Physics and Astronomy, Department of Electrical and Computer Engineering, Rice University, Houston, TX, 77005, USA
b
Department of Physics and Astronomy, Rice University, Houston, TX, 77005, USA
c
Department of Chemistry, Rice University, Houston, TX, 77005, USA
d
Department of Biochemistry and Cell Biology, Rice University, Houston, TX, 77005, USA
We have used an electromigration technique to prepare single-molecule transistors incorporating a family
of transition metal coordination complexes. In a number of these devices, we observe the Kondo effect,
the formation of a correlated many-body state comprising a spin localized to the molecule coupled to
the conduction electrons in the Au leads. We will discuss the temperature dependence of the width and
height of the Kondo resonance, and its variation as a function of transition metal. In devices based on
Co-containing molecules, Kondo temperatures (∼ 70 K) comparable to those seen in scanning tunneling
microscopy of Co atoms on bare Au are observed. The implications of these results, and the prospects
of using single-molecule transistors as model quantum impurity systems will be discussed.
Sorting category: Dc Conducting electrons in condensed matter
Keywords: single-molecule transistor, Kondo, molecular electronics
LT2202