We report the synthesis of oriented single crystalline Mn doped ZnO nanowires through a hydrothermal method. Structural characterizations using X-ray diffraction and transmission electron microscopy revealed that the Mn was doped into the lattice structure, forming solid solution. The Mn doped ZnO nanowires possess wurtzite structure with a c-axis growth orientation. The physical properties of ...

We investigate the possibility of charge carrier localization in magnetic semiconductors due to the presence of a highly inhomogeneous external magnetic field. As an example, we study in detail the properties of a magnetic semiconductor-permalloy disk hybrid system. We find that the giant Zeeman response of the magnetic semiconductor in conjunction with the highly nonuniform magnetic field crea...

–We investigate spin-dependent interband tunnelling in a ferromagnetic (Ga,Mn)As/ GaAs Zener diode. The ferromagnetic pn-junction is fabricated with a Mn-doped p-type GaAs layer on top of a nonmagnetic n-type GaAs substrate. When both sides of the junction are heavily doped, a large magnetic-field–dependent tunnelling effect can be seen at low temperatures in the measured current-voltage (I-V )...

–We investigate spin-dependent interband tunnelling in a ferromagnetic (Ga,Mn)As/ GaAs Zener diode. The ferromagnetic pn-junction is fabricated with a Mn-doped p-type GaAs layer on top of a nonmagnetic n-type GaAs substrate. When both sides of the junction are heavily doped, a large magnetic-field–dependent tunnelling effect can be seen at low temperatures in the measured current-voltage (I-V )...

............................................................................................................................. vi Chapter

A growthwindow for theMn effusion cell temperature (TMn) is demonstrated for epitaxialMn-doped ZnO (MnZnO) thin films grown on sapphire substrates using molecular-beam epitaxy. Within the growth window, the films are ferromagnetic with the largest saturated magnetization occurring at TMn1⁄4700 1C. The Curie temperature of these MnZnO diluted magnetic semiconductor thin films is above roomtemper...

We study spin transport of holes through stubless or stubbed waveguides modulated periodically by diluted magnetic semiconductor (DMS) sections of width b1. Injected holes of up (down) spin feel a periodically modulated barrier (well) potential in the DMS sections and have different transmission (T ) coefficients. T oscillates with b1 for spin-down and decreases fast for spin-up holes while the...