11 research outputs found
Growth and properties of ferromagnetic In(1-x)Mn(x)Sb alloys
We discuss a new narrow-gap ferromagnetic (FM) semiconductor alloy,
In(1-x)Mn(x)Sb, and its growth by low-temperature molecular-beam epitaxy. The
magnetic properties were investigated by direct magnetization measurements,
electrical transport, magnetic circular dichroism, and the magneto-optical Kerr
effect. These data clearly indicate that In(1-x)Mn(x)Sb possesses all the
attributes of a system with carrier-mediated FM interactions, including
well-defined hysteresis loops, a cusp in the temperature dependence of the
resistivity, strong negative magnetoresistance, and a large anomalous Hall
effect. The Curie temperatures in samples investigated thus far range up to 8.5
K, which are consistent with a mean-field-theory simulation of the
carrier-induced ferromagnetism based on the 8-band effective band-orbital
method.Comment: Invited talk at 11th International Conference on Narrow Gap
Semiconductors, Buffalo, New York, U.S.A., June 16 - 20, 200
External control of the direction of magnetization in ferromagnetic InMnAs/GaSb heterostructures
In this paper, we demonstrate external control over the magnetization
direction in ferromagnetic (FM) In_{1-x}Mn_{x}As/GaSb heterostructures. FM
ordering with T_C as high as 50 K is confirmed by SQUID magnetization,
anomalous Hall effect (AHE), and magneto-optical Kerr effect (MOKE)
measurements. Even though tensile strain is known to favor an easy axis normal
to the layer plane, at low temperatures we observe that the magnetization
direction in several samples is intermediate between the normal and in-plane
axes. As the temperature increases, however, the easy axis rotates to the
direction normal to the plane. We further demonstrate that the easy
magnetization axis can be controlled by incident light through a bolometric
effect, which induces a pronounced increase in the amplitude of the AHE. A
mean-field-theory model for the carrier-mediated ferromagnetism reproduces the
tendency for dramatic reorientations of the magnetization axis, but not the
specific sensitivity to small temperature variations.Comment: 11 pages, 3 figures, submitted to NGS-1
Der Einfluss einer Behandlung von Gasflammkohle mit Mineralsaeuren auf deren Hydrierfaehigkeit
Translated from Russian. Originally published in Chimija tverdogo topliva (1978) (no.5) p. 46-4Available from Steinkohlenbergbauverein, Essen (Germany, F.R.) (St-7054) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman