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arXiv · 1010.2008

Parity Broken Chiral Spin Dynamics in Ba$_3$NbFe$_3$Si$_2$O$_{14}$

Mickael Loire·Virginie Simonet·Sylvain Petit·Karol Marty·Pierre Bordet·Pascal Lejay·Jacques Ollivier·Mechthild Enderle·Paul Steffens·Eric Ressouche·Andrej Zorko·Rafik Ballou
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Abstract

The spin wave excitations emerging from the chiral helically modulated 120$^{\circ}$ magnetic order in a langasite Ba$_3$NbFe$_3$Si$_2$O$_{14}$ enantiopure crystal were investigated by unpolarized and polarized inelastic neutron scattering. A dynamical fingerprint of the chiral ground state is obtained, singularized by (i) spectral weight asymmetries answerable to the structural chirality and (ii) a full chirality of the spin correlations observed over the whole energy spectrum. The intrinsic chiral nature of the spin waves elementary excitations is shown in absence of macroscopic time reversal symmetry breaking.

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Mickael Loire, Virginie Simonet, Sylvain Petit, Karol Marty, Pierre Bordet, Pascal Lejay, Jacques Ollivier, Mechthild Enderle, Paul Steffens, Eric Ressouche, Andrej Zorko, Rafik Ballou. 2010-10-11. Parity Broken Chiral Spin Dynamics in Ba$_3$NbFe$_3$Si$_2$O$_{14}$. https://doi.org/10.1103/physrevlett.106.207201

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