Enhanced optical magnetoelectric effect in a patterned polar ferrimagnet.
A simple method to dramatically enhance the optical magnetoelectric (ME) effect, i.e., nonreciprocal directional birefringence, is proposed and demonstrated for a polar ferrimagnet GaFeO3 as a typical example. We patterned a simple grating with a period of 4 microm on a surface of GaFeO3 crystal and used the diffracted light as a probe. The optical ME modulation signal for the Bragg spot of the order n=1 becomes gigantic in the photon energy 1-4 eV and reaches 1-2% of the bare diffracted light intensity in a magnetic field of 500 Oe. This is amplified by more than 3 orders of magnitude compared to that for the reflection of bulk GaFeO3. Fabricating a photonic crystal will make it possible to lead the way for the practical use of the optical ME effect.
Kida
N
N
Spin Superstructure Project (SSS), ERATO, Japan Science and Technology Agency (JST), c/o National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 4, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8562, Japan.
Kaneko
Y
Y
He
J P
JP
Matsubara
M
M
Sato
H
H
Arima
T
T
Akoh
H
H
Tokura
Y
Y