Quantum Amplifier with Spin-polarized Electrons Injection

A promising idea to use the transport of spin-polarized conduction electrons in a magnetic hetero-structure in order to invert population of the charge-carrier spin level in one of its layers, aiming at creation of an active environment for the electromagnetic radiation amplification, has been realized in a number of FMC/SC structures in which FMC is a ferromagnetic conductor and SC is a semiconductor. The n-InSb single crystals, featured by a high mobility of charge carriers, narrow ESR line, and anomalously high absolute value of the negative g-factor (g = -52), were used as SC. The following materials were used as FMC playing a role of spin polarizer: (i) ferromagnetc semiconductors EuO(0.98)Gd(0.02)O and HgCr(2)Se(4), (ii) Geisler alloys Co(2)MnSn, Ni(2)MnSn and Co(2)MnSb. We have demonstrated that the spin-polarized electrons injection into the n-InSb semiconductor from the above-mentioned ferromagnetic materials results in a generation of the laser-type electromagnetic radiation.