TY - JOUR
T1 - Observation of an anisotropic Dirac cone reshaping and ferrimagnetic spin polarization in an organic conductor
AU - Hirata, Michihiro
AU - Ishikawa, Kyohei
AU - Miyagawa, Kazuya
AU - Tamura, Masafumi
AU - Berthier, Claude
AU - Basko, Denis
AU - Kobayashi, Akito
AU - Matsuno, Genki
AU - Kanoda, Kazushi
N1 - Funding Information:
We gratefully acknowledge valuable discussions with Y. Suzumura, N. Nagaosa, H. Isobe, M. Imada, M. Ogata, H. Matsuura, H. Fukuyama, C. Hotta, S. Sugawara, T. Osada, T. Taniguchi, M. Potemski, M.-H. Julien and H. Mayaffre. In particular, we thank M. Horvatić and M. O. Goerbig for their thoughtful advices on the analyses and dedicated discussions. We also thank D. Liu for providing us unpublished results and for fruitful discussions. This work was supported by MEXT/JSPJ KAKENHI under Grant Noes 20110002, 21110519, 24654101, 25220709, 15K05166, 15H02108, JSPS Postdoctoral Fellowship for Research Abroad (Grant No. 66, 2013) and MEXT Global COE Program at University of Tokyo (Global Center of Excellence for the Physical Sciences Frontier; Grant No. G04).
Publisher Copyright:
© 2016 The Author(s).
PY - 2016/8/31
Y1 - 2016/8/31
N2 - The Coulomb interaction among massless Dirac fermions in graphene is unscreened around the isotropic Dirac points, causing a logarithmic velocity renormalization and a cone reshaping. In less symmetric Dirac materials possessing anisotropic cones with tilted axes, the Coulomb interaction can provide still more exotic phenomena, which have not been experimentally unveiled yet. Here, using site-selective nuclear magnetic resonance, we find a non-uniform cone reshaping accompanied by a bandwidth reduction and an emergent ferrimagnetism in tilted Dirac cones that appear on the verge of charge ordering in an organic compound. Our theoretical analyses based on the renormalization-group approach and the Hubbard model show that these observations are the direct consequences of the long-range and short-range parts of the Coulomb interaction, respectively. The cone reshaping and the bandwidth renormalization, as well as the magnetic behaviour revealed here, can be ubiquitous and vital for many Dirac materials.
AB - The Coulomb interaction among massless Dirac fermions in graphene is unscreened around the isotropic Dirac points, causing a logarithmic velocity renormalization and a cone reshaping. In less symmetric Dirac materials possessing anisotropic cones with tilted axes, the Coulomb interaction can provide still more exotic phenomena, which have not been experimentally unveiled yet. Here, using site-selective nuclear magnetic resonance, we find a non-uniform cone reshaping accompanied by a bandwidth reduction and an emergent ferrimagnetism in tilted Dirac cones that appear on the verge of charge ordering in an organic compound. Our theoretical analyses based on the renormalization-group approach and the Hubbard model show that these observations are the direct consequences of the long-range and short-range parts of the Coulomb interaction, respectively. The cone reshaping and the bandwidth renormalization, as well as the magnetic behaviour revealed here, can be ubiquitous and vital for many Dirac materials.
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U2 - 10.1038/ncomms12666
DO - 10.1038/ncomms12666
M3 - Article
AN - SCOPUS:84985001657
SN - 2041-1723
VL - 7
JO - Nature Communications
JF - Nature Communications
M1 - 12666
ER -