Spin-orbit coupling results in technologically-crucial phenomena underlying magnetic devices like magnetic memories and energy-efficient motors. In heavy element materials, the strength of spin-orbit coupling becomes large to affect the overall electronic nature and induces novel states such as topological insulators and spin-orbit-integrated Mott states. Here we report an unprecedented charge-ordering cascade in IrTe 2 without the loss of metallicity, which involves localized spin-orbit Mott states with diamagnetic Ir 4+ -Ir 4+ dimers. The cascade in cooling, uncompensated in heating, consists of first order-type consecutive transitions from a pure Ir 3+ phase to Ir 3+ -Ir 4+ charge-ordered phases, which originate from Ir 5d to Te 5p charge transfer involving anionic polymeric bond breaking. Considering that the system exhibits superconductivity with suppression of the charge order by doping, analogously to cuprates, these results provide a new electronic paradigm of localized charge-ordered states interacting with itinerant electrons through large spin-orbit coupling.
Bibliographical noteFunding Information:
We appreciate the kind support of S.-Y. Park for the XRD measurements. This work was supported by the National Creative Initiative (2009-0081576) and Max Plank POSTECH/ KOREA Research Initiative (2011-0031558) programme through NRF by MSIP of Korea. J.S.K. is also supported by Basic Pesearch Program (2012-013838) through NRF by MSIP of Korea. K.-S.K. is also supported by Basic Research Programs (2012R1A1B3000550 and 2011-0030785) through NRF by MSIP of Korea and by TJ Park Science Fellowship. H.-S.K., T.-H.K., and H.-W.Y. are supported by Institute for Basic Science (IBS) in Korea. The work at Rutgers University was supported by the NSF (NSF-DMREF-1233349) of US. The Pohang Accelerator Laboratory is supported by POSTECH and MSIP of Korea.
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All Science Journal Classification (ASJC) codes
- Biochemistry, Genetics and Molecular Biology(all)
- Physics and Astronomy(all)