Spin Control of Magnetic Molecules with Scanning Tunneling Microscopy
T. Komeda, P. Mishra, J. Liu,
IMRAM, Tohoku University, komeda@tagen.tohoku.ac.jp,
K. Katoh, M. Yamashita,
Tohoku University Department of Chemistry Graduate School of Science
T. Inose, D. Tanaka, T. Ogawa
Osaka University, Department of Chemistry
A research field of molecular spintronics attracts attentions. One of advantages of
organic molecules for the use in spintronics devices is that the spin and electronic states
are strongly correlated with their structures. By using ‘molecule switching’ with outer
stmulations like as current and light, a single spin of a single molecule could be
controlled.
In this paper, I talk about scanning tunneling microscope (STM) study of spin control
of magnetic molecules adsorbed on metal surfaces. Special attentions were paid for
single molecule magnet (SMM) which can store spin information in the molecule.
These molecules include bis(phthalocyaninato)Tb(III) (TbPc2) composed of double
phthalocyanine (Pc) ligands, which shows a high blocking temperature of ~ 40 K, below
which a single SMM molecule works as an quantum magnet, and . The STM plays an
important role in revealing the bonding configuration and interface electronic structure.
Moreover, recent developments enabled STM to access to spin properties of the surface
with the atomic scale resolution. Here, I demonstrate the investigation of the spin state
of the SMM molecule through the detection of the Kondo resonance, which occurs due
to interactions between conduction electrons and the spin of the molecule.
Further, spin manipulations were executed by changing the configurations of the
molecules by injecting tunneling electrons to the molecules. The manipulations include
the rotation of the azimuthal angle of the two Pc planes of the TbPc2 molecule, and
dehydrogenations from the protonated porphyrin double-decker molecules. As the
results of the chemical change of these molecules, the spin state can be switched on/off
in a controlled manner. [1]
Ref. [1] T. Komeda et al., Nat Commun 2 (2011)217; R. Robles et al., Nano Lett. 12
(2012) 3609; J. Liu et al. J. Am. Chem. Soc. 135 (2013) 651; T. Komeda et al., ACS
Nano 7 (2013) 1092; T. Komeda et al., ACS Nano 8, 4866 (2014). F. Wu et al., Nat.
Commun. 6, 7547 (2015).