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Spintronika półprzewodnikowa

Obraz AFM mikrostruktury (Ge,Mn)Te wytworzonej wiązką elektronową. Wiązka elektronowa skanowała amorficzną warstwę (Ge,Mn)Te wzdłuż linii odseparowanych na dystans 10 μm (ciemne obszary na obrazku). Knoff W. et al., physica status solidi b – basic solid state physics 248 (2011) 1605

Angular dependence of the FMR resonant field in (Ge,Mn)Te layer with ferromagnetic microstructures re-crystallized by electron beam irradiation. Two sets of data points correspond to two experimental geometries of the measurements with external magnetic field at ΘH=0 directed either along the line of electron beam scan (dots) or normally to it (triangles). Solid line presents the result of model calculations with anisotropy parameters shownin the figure. Knoff W. et al., physica status solidi b – basic solid state physics 248 (2011) 1605

Scanning electron microscopy image of Mn doped GaAs NWs with Ga droplets at the tops, grown by MBE on oxidized Si(100) substrate in the autocatalytic growth mode. Sadowski J. et al., physica status solidi b - basic solid state physics 248 (2011) 1576

Scanning electron microscope picture of GaAs-GaMnAs core-shell NWs grown on Si(100). Sadowski J. et al., physica status solidi b - basic solid state physics 248 (2011) 1576

Magnetization M(H) and M(T) dependencies measured by SQUID magnetometer for GaAs-GaMnAs core-shell NWs. Sadowski J. et al., physica status solidi b - basic solid state physics 248 (2011) 1576

Materiały termoelektryczne

High-magnification cross-sectional SEM images of the CdTe/PbTe heterostructures initially containing 10 CdTe layers of 2-nm thickness with 25-nm-thick PbTe spacers. Szot M. et al., Crystal Growth & Design 11 (2011) 4794

Cross-sectional TEM image of a CdTe/PbTe multilayer containing one layer of CdTe antidots (top layer) and one layer of PbTe dots (bottom layer) in a properly designed single CdTe/PbTe multilayer subjected to thermal treatment. Szot M. et al., Crystal Growth & Design 11 (2011) 4794

Seebeck coefficient S as a function of electron concentration for CdTe/PbTe antidot heterostructures with initial CdTe layer thicknesses as indicated in the figure. Our experimental data for CdTe/PbTe antidot multilayers (symbols) are compared to the S(n) dependence calculated for n-PbTe bulk crystals (solid line, the so-called Pisarenko plot). Szot M. et al., Crystal Growth & Design 11 (2011) 4794

Materiały optoelektroniczne dla podczerwieni

SEM image of the cross section of 3x[Pb1-xEuxTe/CdTe] heterostructure grown on GaAs(001) substrate with a thick CdTe buffer. Smajek E. et al., Journal of Crystal Growth 323 (2011) 140

 Photoluminescence spectra for Pb1-xEuxTe/CdTe triple quantum wells at T=4.2 K. For clarity the photoluminescence spectra of consecutive heterostructures are shifted vertically by 3 units. Inset presents the scheme of electronic transitions responsible for the observed luminescent radiation. Smajek E. et al., Journal of Crystal Growth 323 (2011) 140

Nanodruty półprzewodnikowe

TEM diffraction image (left panel) and high resolution TEM images (middle and right panel) of the top part of a PbTe NW with a catalyzing gold nanoball. Dziawa P. et al., Crystal Growth & Design 10 (2010) 109

 Dependence of the PbTe NW free energy on the wire diameter for all studied structures. To draw attention to the structure with the lowest energy, RS NWs along the [100] axis, the appropriate points are connected with red line. Dziawa P. et al., Crystal Growth & Design 10 (2010) 109

Topologiczne izolatory krystaliczne

ARPES spectrum in the vicinity of X of the (001) surface of Pb0.77Sn0.23Se monocrystal measured with 10.5 eV photons. The data are recorded along line parallel to the X–M direction, and they clearly show the Dirac-like state at low temperatures. Dziawa P. et al., Nature Materials 11 (2012) 1023

Magnetotransport studies of n-type Pb0.77Sn0.23Se. The temperature dependence of the electron's mobility in the bulk and surface conduction channels. Dziawa P. et al., Nature Materials 11 (2012) 1023