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Multiferroic M-type hexaferrites with a room-temperature conical state and magnetically controllable spin helicity
Y Tokunaga1, Y Kaneko, D Okuyama
1Multiferroics Project, ERATO, Japan Science and Technology Agency (JST), Wako, Saitama 351-0198, Japan.
Physical Review Letters
|January 15, 2011
Summary
Sc-doped barium hexaferrites exhibit tunable magnetic properties, stabilizing a conical state above room temperature. Magnetoelectric measurements reveal control over electric polarization via magnetic fields and temperature.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- M-type barium hexaferrites are known for their magnetic properties.
- Sc-doping offers a route to tune magnetic and magnetoelectric behaviors.
Purpose of the Study:
- Investigate the magnetic and magnetoelectric properties of Sc-doped M-type barium hexaferrites.
- Determine the influence of Sc concentration on magnetic states.
- Explore the control of electric polarization using magnetic fields and temperature.
Main Methods:
- Single crystal growth of Sc-doped M-type barium hexaferrites.
- Magnetization (M) measurements.
- Neutron diffraction.
- Magnetoelectric (ME) measurements.
Main Results:
- Tuning Sc concentration stabilizes a longitudinal conical magnetic state above room temperature.
- Transverse magnetic fields (H) induce electric polarization (P) at lower temperatures.
- Spin helicity is nonvolatile up to the conical magnetic transition temperature.
- The response of the electric polarization vector to magnetic field reversal varies with temperature.
Conclusions:
- Sc-doped M-type barium hexaferrites offer a platform for temperature- and field-controlled magnetoelectric effects.
- The observed phenomena allow for manipulation of the relationship between spin helicity and magnetization vectors.
- This study highlights potential applications in tunable electronic devices.
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