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Search Publications by: Mark D. Stiles (Fed)

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Displaying 26 - 50 of 383

Artifacts That Could Be Misinterpreted as Ballistic Magnetoresistance

October 12, 2021
Author(s)
William F. Egelhoff Jr., L Gan, Erik B. Svedberg, Cedric J. Powell, Alexander J. Shapiro, Robert McMichael, J Mallett, Thomas P. Moffat, Mark D. Stiles
Theoretical physics suggests that very large magnetoresistance (MR) values might be found in certain magnetic nanocontacts if a magnetic domain wall could be localized in them with a length scale that would allow conduction electrons to transit the wall

The Suppression of Orange-Peel Coupling in Magnetic Tunnel Junctions by Pre-Oxidation

October 12, 2021
Author(s)
William F. Egelhoff Jr., Robert McMichael, Cindi L. Dennis, Mark D. Stiles, Alexander J. Shapiro, Brian B. Maranville, Cedric J. Powell
We have have found that pre-oxidation of the bottom Co electrode in magnetic tunnel junctions (MTJs) very effectively suppresses orange-peel coupling. The result is a free layer that is much softer. Work by others has demonstrated that pre-oxidation is

Mutual control of stochastic switching for two electrically coupled superparamagnetic tunnel junctions

August 19, 2021
Author(s)
Philippe Talatchian, Matthew Daniels, Advait Madhavan, Matthew Pufall, Emilie Jue, William Rippard, Jabez J. McClelland, Mark Stiles
Superparamagnetic tunnel junctions (SMTJs) are promising sources for the randomness required by some compact and energy-efficient computing schemes. Coupling them gives rise to collective behavior that could be useful for cognitive computing. We use a

Reservoir computing leveraging the transient non-linear dynamics of spin-torque nano-oscillators

August 6, 2021
Author(s)
Mathieu Riou, Jacob Torrejon, Flavio Abreu Araujo, Sumito Tsunegi, Guru Khalsa, Damien Querlioz, Paolo Bortolotti, Nathan Leroux, Danijela Markovic, Vincent Cros, K. Yakushiji, Akio Fukushima, Hitoshi Kubota, Shinji Yuasa, Mark D. Stiles, Julie Grollier
Present artificial intelligence algorithms require extensive computations to emulate the behavior of large neural networks, operating current computers near their limits, which leads to high energy costs. A possible solution to this problem is the

Phase-resolved electrical detection of coherently coupled magnonic devices

May 20, 2021
Author(s)
Yi Li, Chenbo Zhao, Vivek P. Amin, Zhizhi Zhang, Michael Vogel, Yuzan Xiong, Joseph Sklenar, Ralu Divan, John Pearson, Wei Zhang, Mark D. Stiles, Axel Hoffmann, Valentine Novosad
We demonstrate the electrical detection of a strongly coupled magnon-magnon hybrid system based on yttrium iron garnet/permalloy (YIG/Py) bilayer devices. Direct microwave current injection through the conductive Py layer drives the hybrid dynamics

Roadmap of spin-orbit torques

May 10, 2021
Author(s)
Qiming Shao, Li Peng, Luqiao Liu, Hyunsoo Yang, Shunsuke Fukami, Armin Razavi, Hao Wu, Kang L. Wang, Frank Freimuth, Yuriy Mokrousov, Mark D. Stiles, Satoru Emori, Axel Hoffmann, Johan Akerman, Kaushik Roy, Jian-Ping Wang, See-Hun Yang, Kevin Garello, Wei Zhang
Spin-orbit torque (SOT) is an emerging technology that enables the efficient manipulation of spintronic devices. The initial processes of interest in SOTs involved electric fields, spin- orbit coupling, conduction electron spins and magnetization. More

Topological Control of Magnetic Textures

February 25, 2021
Author(s)
Hanu Arava, Frank P. Barrows, Mark D. Stiles, Amanda K. Petford-Long
A micromagnetic study is carried out on the role of using topology to stabilize different magnetic textures, such as a vortex or an anti-vortex state, in a magnetic heterostructure consisting of a Permalloy disk coupled to a set of nanomagnetic bars. The

Temporal Memory with Magnetic Racetracks

December 1, 2020
Author(s)
Hamed Vakili, Mohammed N. Sakib, Samiran Ganguly, Mircea Stan, Matthew Daniels, Advait Madhavan, Mark D. Stiles, Avik W. Ghosh
Race logic is a relative timing code that represents information in a wavefront of digital edges on a set of wires in order to accelerate dynamic programming and machine learning algorithms. Skyrmions, bubbles, and domain walls are mobile magnetic

Interfacial spin-orbit torques

October 21, 2020
Author(s)
Vivek P. Amin, Paul M. Haney, Mark D. Stiles
Spin-orbit torques offer a promising mechanism to electrically control magnetization dynamics in nanoscale heterostructures. While spin-orbit torques occur predominately at interfaces, the physical mechanisms underlying these torques can originate in both

Storing and retrieving wavefronts with resistive temporal memory

October 10, 2020
Author(s)
Advait Madhavan, Mark D. Stiles
We extend the reach of temporal computing schemes by developing a memory for multi-channel temporal patterns or "wavefronts." This temporal memory re-purposes conventional one-transistor-one-resistor (1T1R) memristor crossbars for use in an arrival-time

Transport dynamics in a high-brightness magneto-optical-trap Li ion source

September 15, 2020
Author(s)
Jamie Gardner, William R. McGehee, Mark D. Stiles, Jabez J. McClelland
Laser-cooled gases offer an alternative to tip-based methods for generating high brightness ions for focused ion beam applications. These sources produce ions by photoionization of ultracold neutral atoms, where the narrow velocity distribution associated