The surface system with adsorbed magnetic atoms is simple but one of the very interesting system. For example, in this system, Kondo effects can be observed in real space imaging using scanning tunneling spectroscopy (STS) [1-3]. In addition, Hirjibehedin et al. [4] show that the conductance spectra of Mn chains detected by STS have strong dependence of the parity of the number of Mn atoms. As shown in ref [4], the conductance spectra have steps at particular bias voltage and these steps can be split by the external magnetic field. From these results, such step may originate from the energy difference of various magnetic states of the magnetic atoms.
In this study, we focus on the effect of the orbital hybridization between magnetic impurities and surface. We think in STS measurement, the hybridization plays the important role in creating a channel of electron tunneling. Also, the bias dependence of spectra may influence the energy of the final states of electron tunneling. In this line, we investigate the spin states and eigenvalues of the initial state and the final state of electron tunneling to estimate the tunneling probability of electron from STM tip to magnetic atoms adsorbed on the metal surface.
References
[1] M. F. Crommie et al., Science 262 (1993) 218
[2] A. J. Heinrich et al., Science 306 (2004) 466
[3] T.Kawasaka et al., Jour. Appl. Phys. 86 (1999) 6970
[4] C. F. Hirjibehedin et al., Science 312 (2006) 1021
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