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Seebeck effect in magnetic tunnel junctions.
The observation of one important effect of this class: the magneto-Seebeck effect, which is observed when a magnetic configuration changes the charge-based Seebeck coefficient during the transition from a parallel to an antiparallel magnetic configuration in a tunnel junction.
Evidence for strong magnon contribution to the TMR temperature dependence in MgO based tunnel junctions
We have prepared MgO based magnetic tunnel junctions which show up to 143% tunneling magnetoresistance (TMR) ratio at room temperature and 205% at 12 K. This TMR temperature dependence is mainly
Memristor-based neural networks
This work presents and explains the relevant mechanisms in a biological neural network, such as long-term potentiation and spike time-dependent plasticity, and determines the minimal requirements for an artificial neural network.
Spin polarization in half-metals probed by femtosecond spin excitation.
It is proposed that this characteristic of femtosecond optical excitation of half-metals enables the establishment of a novel and fast characterization tool for this highly important material class used in spin-electronic devices.
Local charge and spin currents in magnetothermal landscapes.
These findings establish local thermal spin and charge current generation as well as spin caloritronic domain imaging and detect the voltage in the Co2FeAl thin film plane as a function of the laser-spot position and external magnetic field magnitude and orientation.
Temperature dependence of the resistance of magnetic tunnel junctions with MgO barrier
The temperature dependent tunneling resistance of magnetic tunnel junctions with MgO barriers was characterized. In the junctions prepared by magnetron sputtering, the tunnel magnetoresistance
Accessing the fundamentals of magnetotransport in metals with terahertz probes
Spin-dependent conduction in metals underlies all modern magnetic memory technologies, such as giant magnetoresistance (GMR). The charge current in ferromagnetic transition metals is carried by two
Time-resolved measurement of the tunnel magneto-Seebeck effect in a single magnetic tunnel junction.
A setup for time-resolved measurements of thermovoltages and thermocurrents of a single micro- to nanometer-scaled tunnel junction is presented and it is possible to distinguish different Seebeck voltage contributions to the overall measured voltage signal in the μs time regime.
Insights into Ultrafast Demagnetization in Pseudogap Half-Metals
Interest in femtosecond demagnetization dynamics was sparked by Bigot's experiment in 1996, which unveiled the elementary mechanisms that relate the electrons' temperature to their spin order.
Dielectric breakdown in Co–Fe–B/MgO/Co–Fe–B magnetic tunnel junction
The time-dependent dielectric breakdown has been investigated in Co–Fe–B/MgO/Co–Fe–B junctions by voltage ramp experiments and focused on its dependence on the barrier thickness, junction area,