Spin-wave/Carrier-wave interactions

The possibility of spin-wave/carrier-wave interactions has been considered with a more rigorous stability analysis than that used in previous studies. It is concluded that unstable bulk interactions in magnetic semiconductors will not be possible until resistivities are reduced to several orders of magnitude below those presently available. Composite YIG-InSb structures are potentially unstable at room temperature. The composite system can provide high-gain, slow-wave amplification at X-band with delay line capability (2300 dB/cm at 7.5 GHz). In a uniform magnetic field, the instability exhibits an exceedingly narrow bandwidth, 2.5 MHz, which would be a great disadvantage in any practical application as an amplifier. This could be offset somewhat, with a resulting loss of gain, by applying an inhomogeneous magnetic field.