Optical orientation of hole magnetic polarons in (Cd,Mn)Te/(Cd,Mn,Mg)Te quantum wells

Abstract

The optically induced spin polarization in (Cd,Mn)Te/(Cd,Mn,Mg)Te diluted-magneticsemiconductor quantum wells is investigated by means of picosecond pump-probe Kerr rotation. At 1.8 K temperature, additionally to the oscillatory signals from photoexcited electrons and Manganese spins precessing about an external magnetic field, a surprisingly long-lived (up to 60 ns) nonoscillating spin polarization is detected. This polarization is related to optical orientation of equilibrium magnetic polarons involving resident holes. The suggested mechanism for the optical orientation of the equilibrium magnetic polarons indicates that the detected polaron dynamics originates from unexcited magnetic polarons. The polaron spin dynamics is controlled by the anisotropic spin structure of the heavy-hole resulting in a freezing of the polaron magnetic moment in one of the two stable states oriented along the structure growth axis. Spin relaxation between these states is prohibited by a potential barrier, which depends on temperature and magnetic field. The magnetic polaron relaxation is accelerated with increasing temperature and in magnetic field.

Photon‐Induced Spintronic Polaron Channel Modulator of CeO2‐x NP Thin Films Hydrogen Evolution Cells

“…Based on the angular momentum conservation law, the carriers with spin polarization in semiconductors are conveniently generated from circularly polarized light . The relation of polaron polarization and optical orientation is also proved and examined by picosecond pump–probe Kerr rotation . The photoinduced exciton from the semiconductor materials transfers to polaron state excitons into spin‐charge‐carrying on a picosecond time scale .…”

Entangled spintronic modulated high‐performance Ce 2 O 3 small polaron surface state‐based water splitting cells

“…Optically induced spin polarization is utilized to spintronic excitation via electron spin orientation controlling in semiconductor 42 . The optical circuits 43‐46 shown in Figure 3 are designed to modulate the performance of CeO 2‐x NPs water splitting cells by spintronic angular momentum controlling.…”

“…29,32,36 3.2 | CeO 2-x NPs water splitting cells under spin-orbital coupling Optically induced spin polarization is utilized to spintronic excitation via electron spin orientation controlling in semiconductor. 42 The optical circuits [43][44][45][46] shown in Figure 3 are designed to modulate the performance of CeO 2-x NPs water splitting cells by spintronic angular momentum controlling. Circular polarization 405 nm laser with is splitting into two light beams by splitter.…”