Abstract
Spectroscopy reveals a giant coupling of optical second-harmonic generation to the spontaneous polarization in compounds with magnetically driven ferroelectricity. In the symmetry reduction by the ferroelectric order is detected with a sensitivity four orders of magnitude above the resolution limit of . This points to an electronic rather than ionic origin of the spontaneous polarization in joint-order-parameter multiferroics. Hence, our work constitutes an inaugural experimental statement on the controversial theoretical discussion on the nature of the multiferroic polarization.
- Received 11 August 2009
DOI:https://doi.org/10.1103/PhysRevB.80.100101
©2009 American Physical Society