ncku-talk2011-04-20

NCTS (South)

DATE 2011-04-20

TIME 10:30

PLACE Room 815, New Physics Building, NTU

FIELD Computational Materials Research

SPEAKER Dr. Shigeki Onoda - Condensed Matter Theory Lab., RIKEN, Japan

TITLE Chiral spin order and electromagnetic dynamics in one-dimensional multiferroic cuprates

ABSTRACT We show by unbiased numerical calculations that the ferromagnetic nearest-neighbor exchange interaction stabilizes a vector spin chiral order against the quantum fluctuation in a frustrated spin-1/2 chain relevant to multiferroic cuprates, LiCu2O2 and LiCuVO4. Our semi-classical analyses including inter-chain couplings for LiCu2O2 resolve controversies on the helical magnetic structure and unveil the pseudo-Nambu-Goldstone modes as the origin of experimentally observed electromagnons.

[1] S. Furukawa, M. Sato, and S. Onoda, Phys. Rev. Lett. 105, 257205 (2010).

NCTS (South)

DATE	2011-04-20

TIME	10:30

PLACE	Room 815, New Physics Building, NTU

FIELD	Computational Materials Research

SPEAKER	Dr. Shigeki Onoda - Condensed Matter Theory Lab., RIKEN, Japan

TITLE	Chiral spin order and electromagnetic dynamics in one-dimensional multiferroic cuprates

ABSTRACT	We show by unbiased numerical calculations that the ferromagnetic nearest-neighbor exchange interaction stabilizes a vector spin chiral order against the quantum fluctuation in a frustrated spin-1/2 chain relevant to multiferroic cuprates, LiCu2O2 and LiCuVO4. Our semi-classical analyses including inter-chain couplings for LiCu2O2 resolve controversies on the helical magnetic structure and unveil the pseudo-Nambu-Goldstone modes as the origin of experimentally observed electromagnons. [1] S. Furukawa, M. Sato, and S. Onoda, Phys. Rev. Lett. 105, 257205 (2010).