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Search Publications by: Alexander Grutter (Fed)

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Displaying 1 - 25 of 77

Extensive Hydrogen Incorporation is not Necessary for Superconductivity in Topotactically Reduced Nickelates

August 27, 2024
Author(s)
Purnima Balakrishnan, Dan Segedin, Lin Chow, P. Quarterman, Shin Muramoto, Mythili Surendran, Ranjan Patel, Harrison LaBollita, Grace Pan, Qi Song, Yang Zhang, Ismail El Baggari, Koushik Jagadish, Yu-Tsun Shao, Berit Goodge, Lena Kourkoutis, Srimanta Middey, Antia Botana, Jayakanth Ravichandran, A. Ariando, Julia A. Mundy, Alexander Grutter
A key open question in the study of layered superconducting nickelate films is the role that hydrogen incorporation into the lattice plays in the appearance of the superconducting state. Due to the challenges of stabilizing highly crystalline square planar

Vertically Graded FeNi Alloys with Low Damping and a Sizeable Spin-Orbit Torque

June 14, 2024
Author(s)
Rachel Maizel, Shuang Wu, Purnima P. Balakrishnan, Alexander Grutter, Christy Kinane, Andrew Caruana, Prabandha Nakarmi, Bhuwan Nepal, David Smith, Youngmin Lim, Juila Jones, Wyatt Thomas, Jing Zhao, F. Michel, Tim Mewes, Satoru Emori
Energy-efficient spintronic devices require a large spin-orbit torque (SOT) and low damping to excite magnetic precession. In conventional devices with heavy-metal/ferromagnet bilayers, reducing the ferromagnet thickness to ∼1 nm enhances the SOT but drama

Reduction-Induced Magnetic Behavior in LaFeO3-d Thin Films

March 4, 2024
Author(s)
Nathan Arndt, Eitan Hershkovitz, Labdhi Shah, Kristoffer Kjaernes, Chao-Yao Yang, Purnima Balakrishnan, Mohammed Shariff, Shaun Tauro, Daniel Gopman, Brian Kirby, Alexander Grutter, Thomas Tybell, Honggyu Kim, Ryan Need
The effect of oxygen reduction on the magnetic properties of LaFeO3−δ (LFO) thin films was studied to better understand the viability of LFO as a candidate for magnetoionic memory. Differences in the amount of oxygen lost by LFO and its magnetic behavior

Emergent Ferromagnetism in CaRuo3/CaMnO3 (111)-Oriented Superlattices

February 17, 2024
Author(s)
Margaret Kane, Churna Bhandari, Megan Holtz, Purnima Balakrishnan, Alexander Grutter, Michael R. Fitzsimmons, Chao-Yao Yang, Sashi Satpathy, Durga Paudyal, Yuri Suzuki
The boundary between CaRuO3 and CaMnO3 is an ideal test bed for emergent magnetic ground states stabilized through interfacial electron interactions. In this system, nominally antiferromagnetic and paramagnetic materials combine to yield interfacial

Tuning the Magnetic Anisotropy in artificially layered Mn3GaN/Mn3Ga Superlattices

January 31, 2024
Author(s)
Lu Guo, Neil Campbell, Alexander Grutter, Gahee Noh, Tianxiang Nan, P. Quarterman, Si-Young Choi, Thomas Tybell, Mark Rzchowski, Chang-Beom Eom
Artificially layered superlattices with two distinct spin structures offer new opportunities for manipulation of magnetic properties and interfacial spin configurations. We have grown epitaxial, coherent superlattices of ferrimagnetic Mn3Ga and

Controllable Conical Magnetic Structure and Spin-Orbit-Torque Switching in Symmetry-Broken Ferrimagnetic Films

January 23, 2024
Author(s)
Yaqin Guo, Jing Zhang, Purnima Balakrishnan, Alexander Grutter, Baishun Yang, Michael R. Fitzsimmons, Timothy Charlton, Haile Ambaye, Xu Zhang, Hanshen Huang, Zhi Huang, Jinyan Chen, Chenyang Guo, Xiufeng Han, Kang Wang, Hao Wu
Exploring and controlling chiral spin textures has attracted enormous interest from the perspective of fundamental research and spintronic applications. Here, we report the emergence of spiral spin states, bulk spin-orbit torque (SOT), and the

Skyrmion-Excited Spin-Wave Fractal Networks

August 18, 2023
Author(s)
Nan Tang, W. L. N. C. Liyanage, Sergio A. Montoya, Sheena Patel, Lizabeth J. Quigley, Alexander Grutter, Michael R. Fitzsimmons, Sunil Sinha, Julie A. Borchers, Eric E. Fullerton, Lisa Debeer-Schmitt, Dustin A. Gilbert
Magnetic skyrmions exhibit unique, technologically relevant pseudo-particle behaviors which arise from their topological protection, including well-defined, three-dimensional breathing and gyration modes which occur at microwave frequencies. During dynamic

Composite Spin Hall Conductivity from Non-Collinear Antiferromagnetic Order

August 3, 2023
Author(s)
Steve Novakov, Peter B. Meisenheimer, Grace A. Pan, Patrick Kezer, Nguyen M. Vu, Alexander Grutter, Ryan F. Need, Julia Mundy, John Heron
Non-collinear antiferromagnets are an exciting new platform for studying intrinsic spin Hall effects, phenomena that arise from the materials' band structure, Berry phase curvature, and linear response to an external electric field. In contrast to

Constraints on Proximity-Induced Ferromagnetism in a Dirac Semimetal (Cd3As2)/ferromagnetic Semiconductor (Ga1-xMnxSb)heterostructure

June 5, 2023
Author(s)
Arpita Mitra, Run Xiao, Wilson Yanez, Yongxi Ou, Juan Chamorro, Tyrel M. McQueen, Alexander Grutter, Julie Borchers, Michael R. Fitzsimmons, Timothy Charlton, Nitin Samarth
Breaking time-reversal symmetry in a Dirac semimetal Cd3As2 through doping with magnetic ions or by the magnetic proximity effect is expected to cause a transition to other topological phases (such as a Weyl semimetal). To this end, we investigate the

Negligible Magnetic Losses at Low Temperatures in Liquid Phase Epitaxy Grown Y3Fe5O12 Films

May 31, 2023
Author(s)
A. Will-Cole, James L. Hart, Valeria Lauter, Alexander Grutter, Carsten Dubs, Morris Lindner, Timmy Reimann, Nichole R. Valdez, Charles J. Pearce, Todd C. Monson, Judy J. Cha, Don Heiman, Nian X. Sun
Yttrium iron garnet (Y3Fe5O12, YIG) has a unique combination of low magnetic damping, high spin wave conductivity, and insulating properties that make it a highly attractive material for a variety of applications in the fields of magnetics and spintronics

Exchange-Biased Quantum Anomalous Hall Effect

May 19, 2023
Author(s)
Peng Zhang, Purnima P. Balakrishnan, Christopher Eckberg, Peng Deng, Tomohiro Nozaki, Patrick Quarterman, Megan Holtz, Lei Pan, Sukong Chong, Eve Emmanouilidou, Ni Ni, Masashi Sahashi, Alexander Grutter, Kang L. Wang
The quantum anomalous Hall (QAH) effect is characterized by a dissipationless chiral edge state with a quantized Hall resistance at zero magnetic field. Manipulating the QAH state is of great importance in both the understanding of topological quantum

Three-Dimensional Structure of Hybrid Magnetic Skyrmions Determined by Neutron Scattering

May 5, 2023
Author(s)
W. L. N. C. Liyanage, Nan Tang, Lizabeth J. Quigley, Julie A. Borchers, Alexander Grutter, Brian B. Maranville, Sunil Sinha, Nicolas Reyren, Sergio A. Montoya, Eric E. Fullerton, Lisa Debeer-Schmitt, Dustin A. Gilbert
Magnetic skyrmions are topologically protected chiral spin structures which present opportunities for next-generation magnetic data storage and logic information technologies. The topology of these structures originates in the geometric configuration of

Tailoring the Magnetic Exchange Interaction in MnBi2Te4 Superlattices via the Intercalation of Ferromagnetic Layers

January 1, 2023
Author(s)
Peng Chen, Qi Yao, Junqi Xu, Qiang Sun, Alexander Grutter, Patrick Quarterman, Purnima P. Balakrishnan, Christy J. Kinane, Andrew J. Caruana, Sean Langridge, Ang Li, Barat Achinuq, Emily Heppell, Yuchen Ji, Shanshan Liu, Baoshan Cui, Jiuming Liu, Puyang Huang, Zhongkai Liu, Guoqiang Yu, Faxian Xiu, Thorsten Hesjedal, Jin Zou, Xiaodong Han, Haijun Zhang, Yumeng Yang, Xufeng Kou
The intrinsic magnetic topological insulator MnBi 2Te 4 (MBT) has provided a platform for the successful realization of exotic quantum phenomena. To broaden the horizons of MBT-based material systems, we intercalate ferromagnetic MnTe layers to construct

Strain and Charge Contributions to the Magnetoelectric Coupling in Fe 3 O 4 /PMN-PT Artificial Multiferroic Heterostructures

December 30, 2022
Author(s)
Patrick Schoffmann, Anirban Sarkar, Mai H. Hamed, Tanvi Bhatnagar-Schoffmann, Sabine Putter, Brian Kirby, Alexander Grutter, Juri Barthel, Emmanuel Kentzinger, Annika Stellhorn, Andrei Gloskovskii, Martina Muller, Thomas Bruckel
The quest to realize new kinds of data storage devices has motivated recent studies in the field of magnetoelectric heterostructures. One of the most commonly investigated systems is Fe 3O 4/PMN-PT, however, the interplay between different coupling

Topological Surface State Annihilation and Creation in SnTe/Crx(BiSb)2-xTe3 Heterostructures

July 19, 2022
Author(s)
Peng Deng, Alexander Grutter, Yulei Han, Megan E. Holtz, Peng Zhang, Patrick Quarterman, Shuaihang Pan, Shifei Qi, Zhenhua Qiao, Kang L. Wang
Topological surface states are a new class of electronic states with novel properties, including the potential for annihilation between surface states from two topological insulators at a common interface. Here, we report the annihilation and creation of

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