Publications (12)
Transport Characterization of the Magnetic Anisotropy of (Ga,Mn)As
K. Pappert, S. Hümpfner, J. Wenisch +4
The rich magnetic anisotropy of compressively strained (Ga,Mn)As has attracted great interest recently. Here we discuss a sensitive method to visualize and quantify the individual…
Fully electrically read-write device out of a ferromagnetic semiconductor
S. Mark, P. Dürrenfeld, K. Pappert +4
We report the realization of a read-write device out of the ferromagnetic semiconductor (Ga,Mn)As as the first step to fundamentally new information processing paradigm. Writing th…
An extensive comparison of anisotropies in MBE grown (Ga,Mn)As material
C. Gould, S. Mark, K. Pappert +14
This paper reports on a detailed magnetotransport investigation of the magnetic anisotropies of (Ga,Mn)As layers produced by various sources worldwide. Using anisotropy fingerprint…
Current Assisted Magnetization Switching in (Ga,Mn)As Nanodevices
C. Gould, K. Pappert, C. Rüster +6
Current induced magnetization switching and resistance associated with domain walls pinned in nanoconstrictions have both been previously reported in (Ga,Mn)As based devices, but u…
Independent magnetization behavior of a ferromagnetic metal/semiconductor hybrid system
S. Mark, C. Gould, K. Pappert +4
We report the discovery of an effect where two ferromagnetic materials, one semiconductor ((Ga,Mn)As) and one metal (permalloy), can be directly deposited on each other and still s…
Exploiting Locally Imposed Anisotropies in (Ga,Mn)As: a Non-volatile Memory Device
K. Pappert, S. Hümpfner, C. Gould +4
Progress in (Ga,Mn)As lithography has recently allowed us to realize structures where unique magnetic anisotropy properties can be imposed locally in various regions of a given dev…
Control of magnetic anisotropy in (Ga,Mn)As by lithography-induced strain relaxation
J. Wenisch, C. Gould, L. Ebel +7
We obtain control of magnetic anisotropy in epitaxial (Ga,Mn)As by anisotropic strain relaxation in patterned structures. The strain in the structures is characterized using sophis…
Bound hole states in a ferromagnetic (Ga,Mn)As environment
M. J. Schmidt, K. Pappert, C. Gould +3
A numerical technique is developed to solve the Luttinger-Kohn equation for impurity states directly in k-space and is applied to calculate bound hole wave functions in a ferromagn…
Diffusion thermopower of (Ga,Mn)As/GaAs tunnel junctions
Ts. Naydenova, P. Dürrenfeld, K. Tavakoli +6
We report the observation of tunneling anisotropic magnetothermopower, a voltage response to a temperature difference across an interface between a normal and a magnetic semiconduc…
Magnetization-Switched Metal-Insulator Transition in a (Ga,Mn)As Tunnel Device
K. Pappert, M. J. Schmidt, S. Hümpfner +6
We observe the occurrence of an Efros-Shklovskii gap in (Ga,Mn)As based tunnel junctions. The occurrence of the gap is controlled by the extent of the hole wave-function on the Mn…
Lithographic engineering of anisotropies in (Ga,Mn)As
S. Hümpfner, M. Sawicki, K. Pappert +6
The focus of studies on ferromagnetic semiconductors is moving from material issues to device functionalities based on novel phenomena often associated with the anisotropy properti…
Detailed transport investigation of the magnetic anisotropy of (Ga,Mn)As
K. Pappert, C. Gould, M. Sawicki +4
This paper discusses transport methods for the investigation of the (Ga,Mn)As magnetic anisotropy. Typical magnetoresistance behaviour for different anisotropy types is discussed,…