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Ultrafast magnetization reversal by picosecond electrical pulses
Yang Yang1, Richard B Wilson2, Jon Gorchon3,4
1Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, CA 94720, USA.
Science Advances
|November 10, 2017
Summary
Researchers demonstrate ultrafast magnetic switching using electrical pulses. This new spintronic method achieves magnetization reversal in picoseconds, offering a faster and more energy-efficient approach for future devices.
Area of Science:
- Spintronics
- Ultrafast Magnetism
- Materials Science
Background:
- Spintronics studies spin and charge transport in solid-state devices.
- Ultrafast magnetism manipulates magnetic order on subpicosecond timescales using femtosecond laser pulses.
Purpose of the Study:
- To unite spintronics and ultrafast magnetism by using electrical pulses to excite conduction electrons in magnetic metals.
- To demonstrate a novel method for ultrafast magnetic switching.
Main Methods:
- Utilized picosecond electrical current pulses to excite conduction electrons in magnetic metals.
- Investigated magnetization reversal in a Gadolinium-Iron-Cobalt (GdFeCo) thin film.
Main Results:
- Achieved deterministic and repeatable ultrafast magnetization reversal in a GdFeCo thin film using a single sub-10-picosecond electrical pulse.
- Demonstrated magnetization reversal in approximately 10 picoseconds, over an order of magnitude faster than existing electrical switching methods.
- Identified a new electrical switching mechanism independent of spin-polarized currents or spin-transfer/orbit torques.
Conclusions:
- Introduced a fundamentally new electrical switching mechanism for spintronics.
- Established a new research field of ultrafast charge current-driven spintronic phenomena and devices.
- Showcased low energy density requirements for switching, projecting 4 fJ for a (20 nm)³ cell.
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