Progress toward picosecond on-chip magnetic memory
Abstract
We offer a perspective on the prospects of ultrafast spintronics and opto-magnetism as a pathway to high-performance, energy-efficient, and non-volatile embedded memory in digital integrated circuit applications. Conventional spintronic devices, such as spin-transfer-torque magnetic-resistive random-access memory (STT-MRAM) and spin–orbit torque MRAM, are promising due to their non-volatility, energy-efficiency, and high endurance. STT-MRAMs are now entering into the commercial market; however, they are limited in write speed to the nanosecond timescale. Improvement in the write speed of spintronic devices can significantly increase their usefulness as viable alternatives to the existing CMOS-based devices. In this article, we discuss recent studies that advance the field of ultrafast spintronics and opto-magnetism. An optimized ferromagnet–ferrimagnet exchange-coupled magnetic stack, which can serve as the free layer of a magnetic tunnel junction (MTJ), can be optically switched in as fast as ∼3 ps. Integration of ultrafast magnetic switching of a similar stack into an MTJ device has enabled electrical readout of the switched state using a relatively larger tunneling magnetoresistance ratio. Purely electronic ultrafast spin–orbit torque induced switching of a ferromagnet has been demonstrated using ∼6 ps long charge current pulses. We conclude our Perspective by discussing some of the challenges that remain to be addressed to accelerate ultrafast spintronics technologies toward practical implementation in high-performance digital information processing systems.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Apr 04, 2022
- Source ID
- 10.1063/5.0083897
Entities
People
- Akshay Pattabi
- Debanjan Polley
- Hanuman Singh
- Jeffrey Bokor
- Jon Gorchon
- Jyotirmoy Chatterjee
- Kaushalya Jhuria
- Sucheta Mondal
Organizations
- Defense Advanced Research Projects Agency
- Fraunhofer Institute for Photonic Microsystems
- Lawrence Berkeley National Laboratory
- National Science Foundation
- University of California
- University of Lorraine