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Thomas J. Silva, Justin M. Shaw, Hans T. Nembach, Mathias A. Weiler
Sources of pure spin currents are a fundamental building block of spintronic devices. In ferromagnet/normal metal heterostructures, spin currents are generated at ferromagnetic resonance. This is known as spin pumping, where spin currents of both dc and ac
Hyuk-Jae Jang, Sujitra J. Pookpanratana, Alyssa N. Brigeman, Regis J. Kline, James I. Basham, David J. Gundlach, Christina A. Hacker, Oleg A. Kirillov, Oana Jurchescu, Curt A. Richter
Organic semiconductors hold immense promise for the development of a wide range of innovative devices with their excellent electronic and manufacturing characteristics. Of particular interest are non-magnetic organic semiconductors that show unusual
Eric R. Evarts, Ranko R. Heindl, William H. Rippard, Matthew R. Pufall
In a small fraction of magnetic-tunnel-junction-based MRAM devices with in-plane free layers, the write error rates (WERs) are higher than expected on the basis of the macrospin or quasi-uniform magnetization reversal models. In devices with increased WERs
Burm Baek, William H. Rippard, Samuel P. Benz, Stephen E. Russek, Paul D. Dresselhaus
The quantum behavior of Josephson junctions is often exploited to produce superconducting devices with outstanding performance. Josephson junctions can also be used in circuits that perform logic operations in picoseconds and may enable high-performance
We report parametric excitation of magnetic precession modes in nanodisks using a parallel pumping configuration. The excitations are detected using a ferromagneitc resonance force microscopy method, and the parallel-pumped spectra reveal nonlinear
Thomas J. Silva, Mathias A. Weiler, Hans T. Nembach, Justin M. Shaw
In a recent Letter, Hahn et al. reported on the detection of an ac voltage in a yttrium iron garnet (YIG)/platinum (Pt) bilayer under the condition of parametrically excited resonance. The authors observe an ac voltage at the frequency of the magnetization
Jacob M. Taylor, Medford Jim, Johannes Beil, Stephen Bartlett, Andrew Doherty, Emmanuel Rashba, David P. DiVincenzo, H Lu, A. C. Gossard
We demonstrate the initialization, full electrical control, and state tomography of an exchange- only spin qubit in a GaAs heterostructure. Decoherence and leakage from the qubit subspace are accounted for with a model of charge noise and fluctuating
We present a modulated microwave approach for quantum computing with qubits comprising three spins in a triple quantum dot. This approach includes single- and two-qubit gates that are protected against low-frequency electrical noise, due to an operating
Jacob M. Taylor, Medford Jim, Johannes Beil, Emmanuel Rashba, H Lu, A. C. Gossard, C. M. Marcus
We introduce a solid-state qubit in which exchange interactions among confined electrons provide both the static longitudinal field and the oscillatory transverse field, allowing rapid and full qubit control via rf gate-voltage pulses. We demonstrate two
Burm Baek, Samuel P. Benz, William H. Rippard, Stephen E. Russek, Paul D. Dresselhaus, Horst Rogalla, Matthew R. Pufall
If Josephson and spintronic technologies can be successfully integrated to produce a cryogenic memory that can be controlled with single-flux quantum pulses, then they may enable ultra-low-power, high-speed computing. We have developed hybrid Josephson
Eric R. Evarts, Matthew R. Pufall, William H. Rippard
We quantitatively compare film-level ferromagnetic resonance (FMR) measurements to device-level FMR measurements on magnetic tunnel junction (MTJ) thin films with in-plane magnetization using both thermal FMR (T-FMR) and field-swept spin torque FMR
We use broadband ferromagnetic resonance spectroscopy and x-ray diffraction to investigate the fundamental origin of perpendicular anisotropy in Co 90Fe 10/Ni multilayers. By careful evaluation of the spectroscopic g-factor, we determine the orbital moment
Stephen E. Russek, Ranko R. Heindl, Thomas Cecil, William H. Rippard
Spin transfer nano-oscillators are small multilayer magnetic devices that undergo microwave oscillations and output a microwave voltage when a bias current is applied. The oscillation frequency is tunable, over a range of 0.5 GHz to 225 GHz, by varying the