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Search Publications by: Alexander Grutter (Fed)

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Displaying 26 - 50 of 82

Engineering Magnetic Anisotropy and Emergent Multidirectional Soft Ferromagnetism in Ultrathin Freestanding LaMnO 3 Films

May 24, 2022
Author(s)
Qinwen Lu, Zhiwei Liu, Qun Yang, Hui Cao, Purnima P. Balakrishnan, Qing Wang, Long Cheng, Yalin Lu, Jian-Min Zuo, Hua Zhou, Patrick Quarterman, Shinichiro N. Muramoto, Alexander Grutter, Hanghui Chen, Xiaofang Zhai
Owing to their small coercive fields and weak magnetic anisotropy, soft ferromagnetic films are extremely useful for nanoscale devices that need to easily switch spin directions. However, they are rare, particularly when a film thickness is reduced to a

Understanding Signatures of Emergent Magnetism in Topological Insulator/Ferrite Bilayers

March 24, 2022
Author(s)
Lauren J. Riddiford, Alexander Grutter, Timothy Pillsbury, Max Stanley, Danielle Reifsnyder Hickey, Peng Li, Nasim Alem, Nitin Samarth, Yuri Suzuki
Magnetic insulator and topological insulator heterostructures have been studied in search of induced magnetism in the topological insulator, but chiral edge states have been elusive. We have identified MgAl 0.5Fe 1.5O 4/Bi 2Se 3 bilayers for a possible

Spin and Charge Interconversion in Dirac-Semimetal Thin Films

November 16, 2021
Author(s)
Wilson Yanez, Yongxi Ou, Run Xiao, Jahyun Koo, Jacob T. Held, Supriya Ghosh, Jeffrey Rable, Timothy Pillsbury, Enrique Gonzalez Delgado, Kezhou Yang, Juan Chamorro, Alexander Grutter, Patrick Quarterman, Anthony Richardella, Abhronil Sengupta, Tyrel M. McQueen, Julie Borchers, K. A. Mkhoyan, Binghai Yan, Nitin Samarth
We report spin-to-charge and charge-to-spin conversion at room temperature in heterostructure devices that interface an archetypal Dirac semimetal, Cd 3As 2, with a metallic ferromagnet,Ni 0.80Fe 0.20 (permalloy). The spin-charge interconversion is

Magnetic Field-Induced Non-Trivial Electronic Topology in Fe 3-x GeTe 2

October 7, 2021
Author(s)
Juan Macy, Danilo Ratkovski, Purnima P. Balakrishnan, Mara Strungaru, Yu-Che Chiu, Aikaterini Flessa, Alex Moon, Wenkai Zheng, Ashley Weiland, Gregory T. McCandless, Julia Y. Chan, Govind S. Kumar, Michael Shatruk, Alexander Grutter, Julie Borchers, William D. Ratcliff, Eun S. Choi, Elton J. Santos, Luis Balicas
The anomalous Hall, Nernst and thermal Hall coefficients of the itinerant ferromagnet Fe 3−xGeTe 2 display several features upon cooling, like a reversal in the Nernst signal below T = 50 K pointing to a topological transition possibly associated to the

Antiferromagnetic VdW Phase at the Interface of Sputtered Topological Insulator/Ferromagnet Bi 2 Te 3 /Ni 80 Fe 2 0 Heterostructures

October 6, 2021
Author(s)
Nirjhar Bhattacharjee, Krishnamurthy Mahalingam, Adrian Fedorko, Valeria Lauter, Matthew Matzelle, Bahadur Singh, Alexander Grutter, Alexandria Will-Cole, Michael Page, Michael McConney, Robert Markiewicz, Arun Bansil, Don Heiman, Nian Sun
Magnetic ordering in topological insulators (TI) is crucial for breaking time-reversal symmetry (TRS) and thereby opening a gap in the topological surface states (TSSs) [1-6], which is the key for realizing useful topological properties such as the quantum

Elucidating Proximity Magnetism through Polarized Neutron Reflectometry and Machine Learning

September 16, 2021
Author(s)
Nina Andrejevic, Zhantao Chen, Thanh Nguyen, Leon Fan, Henry Heiberger, Valeria Lauter, Ling-Jie Zhou, Yi-Fan Zhao, Cui-Zu Chang, Alexander Grutter, Mingda Li
Polarized neutron reflectometry (PNR) is a powerful technique to interrogate the structures of multilayered magnetic materials with depth sensitivity and nanometer resolution. However, reflectometry profiles often inhabit a complicated objective function

Magnetic proximity effect in magnetic-insulator/heavy-metal heterostructures across the compensation temperature

September 1, 2021
Author(s)
Jackson Bauer, Patrick Quarterman, Alexander Grutter, Bharat Khurana, Subhajit Kundu, K. Mkhoyan, Julie A. Borchers, Caroline Ross
The magnetic proximity effect in Pt and W thin films grown on Dy3Fe5O12 (DyIG) is examined at temperatures above and below the magnetic compensation temperature of the ferrimagnetic insulator. Polarized neutron reflectometry indicates that the proximity

Electrically Driven Exchange Bias via Solid State Magneto-Ionics

August 4, 2021
Author(s)
Peyton Murray, Christopher Jensen, Alberto Quintana, Junwei Zhang, Xixiang Zhang, Alexander Grutter, Brian Kirby, Kai Liu
Electrically induced ionic motion offers a new way to realize voltage-controlled magnetism, opening the door to a new generation of logic, sensor, and data storage technologies. Here, we demonstrate an effective approach to magneto-ionically and

Resonant Spin Transmission Mediated by Magnons in a Magnetic Insulator Multilayer Structure

June 3, 2021
Author(s)
Yabin Fan, Joseph Finley, Jiahao Han, Megan E. Holtz, Patrick Quarterman, Pengxiang Zhang, Taqiyyah S. Safi, Justin T. Hou, Alexander Grutter, Luqiao Liu
One important goal of magnonics is to discover novel wave properties of magnons, which are quanta of collective excitation in magnets, to make it compatible for application on coherent information transmission and processing1,2. However, thin-film

Exchange Bias Switching in an Antiferromagnet/Ferromagnet Bilayer Driven by Spin-Orbit Torque

December 1, 2020
Author(s)
Shouzhong Peng, Daoqian Zhu, Weixiang Li, Hao Wu, Alexander Grutter, Dustin A. Gilbert, Jiaqi Lu, Danrong Xiong, Wenlong Cai, Padraic Shafer, Kang L. Wang, Weisheng Zhao
Electrical manipulation of exchange bias and magnetization in antiferromagnet/ferromagnet thin films has been of great interest in recent years. Here, we experimentally demonstrate current-induced switching of exchange bias in perpendicularly magnetized

Large Exchange Splitting in Monolayer Graphene Magnetized by an Antiferromagnet

September 30, 2020
Author(s)
Yingying Wu, Gen Yin, Lei Pan, Alexander Grutter, Quanjun Pan, Albert Lee, Dustin A. Gilbert, Julie A. Borchers, William D. Ratcliff, Ang Li, Xiao-dong Han, Kang L. Wang
Spin splitting in graphene has been identified as a key component for unlocking multifunctionality with low dissipation and long-distance spin transport. Magnetic proximity effects are an extremely promising route to realizing exchange splitting in

Observation of Quantum Anomalous Hall Effect and Exchange Interaction in Topological Insulator/Antiferromagnet Heterostructure

August 27, 2020
Author(s)
Lei Pan, Alexander Grutter, Peng Zhang, Xiaoyu Che, Tomohiro Nozaki, Alex Stern, Mike Street, Bing Zhang, Brian Casas, Qing L. He, Eun S. Choi, Steven M. Disseler, Dustin Gilbert, Gen Yin, Qiming Shao, Peng Deng, Yingying Wu, Xiaoyang Liu, Xufeng Kou, Sahashi Masashi, Xiaodong Han, Christian Binek, Scott Chambers, Jing Xia, Kang L. Wang
Integration of a quantum anomalous Hall insulator with a magnetically ordered material provides an additional degree of freedom through which we may control the resulting exotic quantum states. Here, we report an experimental observation of the quantum

Termination Switching of Antiferromagnetic Proximity Effect in Topological Insulator

August 12, 2020
Author(s)
Chao-Yao Yang, Lei Pan, Alexander Grutter, Haiying Wang, Xiaoyu Che, Qing L. He, Yingying Wu, Dustin A. Gilbert, Padraic Shafer, Elke Arenholz, Hao Wu, Gen Yin, Peng Deng, Julie Borchers, William D. Ratcliff, Kang L. Wang
The magnetic proximity effect (MPE) allows exchange-coupling of topological insulators (TIs) with magnetically ordered materials to break time-reversal-symmetry and open a gap in the Dirac-cone surface state, with the goal of realizing quantum anomalous

Differentiation between Strain and Charge Mediated Magnetoelectric Coupling in La 0.7 Sr 0.3 MnO 3 /Pb(Mg 1/3 Nb 2/3) d0.7^Ti 0.3 O 3 (001)

June 17, 2020
Author(s)
T. Bhatnagar-Schoffmann, Emmanuel Kentzinger, A. Sarkar, P. Schoffmann, Q. Lan, L. Jin, A. Kovacs, Alexander Grutter, Brian Kirby, R. Beerwerth, M. Waschk, Annika Stellhorn, U. Rucker, R. E. Dunin-Borkowski, Th. Bruckel
Magnetoelectric (ME) coupling in La 0.7Sr 0.3MnO 3/Pb(Mg 1/3Nb 2/3)d0.7^Ti 0.3O 3 (LSMO/PMN-PT (001)) has been probed in the past years to identify the underlying mechanism behind it. PMN-PT, which is well known for its excellent piezoelectric properties

Manipulation of Coupling and Magnon Transport in Magnetic Metal-Insulator Hybrid Structures

June 15, 2020
Author(s)
Yabin Fan, Patrick Quarterman, Joseph Finley, Jiahao Han, Pengxiang Zhang, Justin T. Hou, Mark D. Stiles, Alexander Grutter, Luqiao Liu
Ferromagnetic metals and insulators are widely used for generation, control and detection of magnon spin signals. Most magnonic structures are based primarily on either magnetic insulators or ferromagnetic metals, while heterostructures integrating both of

Correlation-Driven Eightfold Magnetic Anisotropy in a Two-Dimensional Oxide Monolayer

April 10, 2020
Author(s)
Zhangzhang Cui, Alexander Grutter, Hua Zhou, Hui Cao, Yongqi Dong, Dustin A. Gilbert, Jingyuan Wang, Yi-Sheng Liu, Jiaji Ma, Zhenpeng Hu, Jinghua Guo, Jing Xia, Brian Kirby, Padraic Shafer, Elke Arenholz, Hanghui Chen, Xiaofang Zhai, Yalin Lu
Engineering magnetic anisotropy (MA) in two-dimensional (2D) ferromagnetic materials has enormous scientific and technological implications. The uniaxial anisotropy universally exhibited by 2D ferromagnetic materials has only two stable spin directions

Strain-Induced Majority Carrier Inversion in Ferromagnetic Epitaxial LaCoO^d3-d Thin Films

March 4, 2020
Author(s)
Vipul Chaturvedi, Jeff Walter, Arpita Paul, Alexander Grutter, Brian Kirby, Jong Seok Jeong, Hua Zhou, Zhan Zhang, Biqiong Yu, Martin Greven, K. Andre Mkhoyan, Turan Birol, Chris Leighton
Tensile-strained LaCoO 3-δ thin films are ferromagnetic, in sharp contrast to the zero-spin bulk, although no clear consensus has emerged as to the origin of this phenomenon. While magnetism has been heavily studied, relatively little attention has been

Emergent Electric Field Control of Phase Transformation in Oxide Superlattices

February 1, 2020
Author(s)
Di Yi, Yujia Wang, Olaf M. J. van t'Erve, Liubin Xu, Hongtao Yuan, Michael J. Veit, Purnima P. Balakrishnan, Yongseong Choi, Alpha T. N'Diaye, Padraic Shafer, E. Arenholz, Alexander Grutter, Haixuan Xu, Pu Yu, Berend T. Jonker, Yuri Suzuki
Electric fields have been shown to transform materials with respect to their structure and properties, thus enabling many applications ranging from batteries to spintronics. Recently electrolytic gating, which can generate large electric fields and voltage

Dysprosium Iron Garnet Thin Films with Perpendicular Magnetic Anisotropy on Silicon

January 1, 2020
Author(s)
Jackson J. Bauer, Ethan R. Rosenberg, Subhajit Kundu, K. Andre Mkhoyan, Patrick Quarterman, Alexander Grutter, Brian Kirby, Julie Borchers, Caroline A. Ross
Magnetic insulators, such as the rare-earth iron garnets, are promising materials for energy-efficient spintronic memory and logic devices, and their anisotropy, magnetization and other properties can be tuned over a wide range through selection of the

Damping Enhancement in Coherent Ferrite-Insulating-Paramagnet Bilayers

November 19, 2019
Author(s)
Jacob J. Wisser, Alexander Grutter, Dustin A. Gilbert, Alpha T. N'Diaye, Christoph Klewe, Padraic Shafer, Elke Arenholz, Yuri Suzuki, Satoru Emori
High-quality epitaxial ferrites, such as low-damping MgAl-ferrite (MAFO), are promising nanosclae building blocks for all-oxide heterostructures driven by pure spin current. However, the impact of oxide interfaces on spin dynamics in such heterostructures

Tunable Magnetic Ordering through Cation Selection in Entropic Spinel Oxides

October 21, 2019
Author(s)
Brianna Musico, Quinton Wright, T. Zac Ward, Alexander Grutter, Elke Arenholz, Dustin Gilbert, David Mandrus, Veerle Keppens
Twelve multicomponent spinels, comprised of (Mg, Cr, Mn, Co, Fe, Ni, Cu, and/or Zn)(Cr, Fe or Al) 2O 4, were prepared using solid state synthesis methods, resulting in nine homogenous, single phase samples with a Fm-3m structure, and three samples with

Ultrathin Interfacial Layer with Suppressed Room Temperature Magnetization in Magnesium Aluminum Ferrite Thin Films

September 24, 2019
Author(s)
Jacob J. Wisser, Satoru Emori, Lauren Riddiford, Aaron Altman, Peng Li, Krishnamurthy Mahalingam, Brittany T. Urwin, Brandon M. Howe, Michael R. Page, Alexander Grutter, Brian Kirby, Yuri Suzuki
Low-damping magnetic oxide thin films with small thicknesses are essential for efficient insulator spintronic devices, particularly those driven by spin torques effects. Here, we investigate depth-resolved compositional and magnetic properties of epitaxial