Local probe of fractional edge states of S=1 Heisenberg spin chains

Spin chains are among the simplest physical systems in which electron-electron interactions induce novel states of matter. Here we propose to combine atomic scale engineering and spectroscopic capabilities of state of the art scanning tunnel microscopy to probe the fractionalized edge states of individual atomic scale S=1 spin chains. These edge states arise from the topological order of the ground state in the Haldane phase. We also show that the Haldane gap and the spin-spin correlation length can be measured with the same technique.

This work has been financially supported by MEC-Spain (Grants No. FIS2010-21883-C02-01, No. FIS2009-08744, and No. CONSOLIDER CSD2007-0010), European Union as well as Generalitat Valenciana, Grant No. Prometeo 2012-11. This work was carried out under the auspices of the NNSA of the U.S. DOE at LANL under Contract No. DE-AC52-06NA25396, and was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering. This Letter is based upon work supported in part by the NSF under Grant No. PHY-1066293 and the hospitality of the Aspen Center for Physics.