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Title: Spintronics Meets Density Matrix Renormalization Group: Quantum Spin-Torque-Driven Nonclassical Magnetization Reversal and Dynamical Buildup of Long-Range Entanglement

Abstract

We introduce the time-dependent density matrix renormalization group (tDMRG) as a solution to a longstanding problem in spintronics—how to describe spin-transfer torque (STT) between flowing spins of conduction electrons and localized spins within a magnetic material by treating the dynamics of both spin species fully quantum mechanically. In contrast to conventional Slonczewski-Berger STT, where the localized spins are viewed as classical vectors obeying the Landau-Lifshitz-Gilbert equation and where their STT-driven dynamics is initiated only when the spin polarization of flowing electrons and localized spins are noncollinear, quantum STT can occur when these vectors are collinear but antiparallel. Using tDMRG, we simulate the time evolution of a many-body quantum state of electrons and localized spins, where the former are injected as a spin-polarized current pulse while the latter comprise a quantum Heisenberg ferromagnetic metallic (FM) spin-1/2 XXZ chain initially in the ground state with spin polarization antiparallel to that of injected electrons. The quantum STT reverses the direction of localized spins, but without rotation from the initial orientation, when the number of injected electrons exceeds the number of localized spins. Such nonclassical reversal, which is absent from Landau-Lifshitz-Gilbert dynamics, is strikingly inhomogeneous across the FM chain, and it can be accompaniedmore » by reduction of the magnetization associated with localized spins, even to zero at specific locations. This feature arises because quantum STT generates a highly entangled nonequilibrium many-body state of all flowing and localized spins, despite starting from the initially unentangled ground state of a mundane FM. Furthermore, the mutual information between localized spins at the FM edges remains nonzero even at infinite separation as the signature of dynamical buildup of long-range entanglement. The growth in time of entanglement entropy differentiates between the quantum and conventional (i.e., noncollinear) setups for STT, reaching a much larger asymptotic value in the former case.« less

Authors:
ORCiD logo; ; ORCiD logo; ORCiD logo; ORCiD logo
Publication Date:
Research Org.:
Northeastern Univ., Boston, MA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES); US Army Research Office (ARO); National Science Foundation (NSF)
OSTI Identifier:
1798235
Alternate Identifier(s):
OSTI ID: 1852999
Grant/Contract Number:  
SC0019275; W911NF-14-0247; ECCS-1922689
Resource Type:
Published Article
Journal Name:
Physical Review. X
Additional Journal Information:
Journal Name: Physical Review. X Journal Volume: 11 Journal Issue: 2; Journal ID: ISSN 2160-3308
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; Physics; Entanglement detection; Entanglement entropy; Entanglement production; Magnetization dynamics; Magnetization switching; Open quantum systems & decoherence; Spin transfer torque; Density matrix renormalization group; Kondo lattice model; Spin chains

Citation Formats

Petrović, Marko D., Mondal, Priyanka, Feiguin, Adrian E., Plecháč, Petr, and Nikolić, Branislav K. Spintronics Meets Density Matrix Renormalization Group: Quantum Spin-Torque-Driven Nonclassical Magnetization Reversal and Dynamical Buildup of Long-Range Entanglement. United States: N. p., 2021. Web. doi:10.1103/PhysRevX.11.021062.
Petrović, Marko D., Mondal, Priyanka, Feiguin, Adrian E., Plecháč, Petr, & Nikolić, Branislav K. Spintronics Meets Density Matrix Renormalization Group: Quantum Spin-Torque-Driven Nonclassical Magnetization Reversal and Dynamical Buildup of Long-Range Entanglement. United States. https://doi.org/10.1103/PhysRevX.11.021062
Petrović, Marko D., Mondal, Priyanka, Feiguin, Adrian E., Plecháč, Petr, and Nikolić, Branislav K. Wed . "Spintronics Meets Density Matrix Renormalization Group: Quantum Spin-Torque-Driven Nonclassical Magnetization Reversal and Dynamical Buildup of Long-Range Entanglement". United States. https://doi.org/10.1103/PhysRevX.11.021062.
@article{osti_1798235,
title = {Spintronics Meets Density Matrix Renormalization Group: Quantum Spin-Torque-Driven Nonclassical Magnetization Reversal and Dynamical Buildup of Long-Range Entanglement},
author = {Petrović, Marko D. and Mondal, Priyanka and Feiguin, Adrian E. and Plecháč, Petr and Nikolić, Branislav K.},
abstractNote = {We introduce the time-dependent density matrix renormalization group (tDMRG) as a solution to a longstanding problem in spintronics—how to describe spin-transfer torque (STT) between flowing spins of conduction electrons and localized spins within a magnetic material by treating the dynamics of both spin species fully quantum mechanically. In contrast to conventional Slonczewski-Berger STT, where the localized spins are viewed as classical vectors obeying the Landau-Lifshitz-Gilbert equation and where their STT-driven dynamics is initiated only when the spin polarization of flowing electrons and localized spins are noncollinear, quantum STT can occur when these vectors are collinear but antiparallel. Using tDMRG, we simulate the time evolution of a many-body quantum state of electrons and localized spins, where the former are injected as a spin-polarized current pulse while the latter comprise a quantum Heisenberg ferromagnetic metallic (FM) spin-1/2 XXZ chain initially in the ground state with spin polarization antiparallel to that of injected electrons. The quantum STT reverses the direction of localized spins, but without rotation from the initial orientation, when the number of injected electrons exceeds the number of localized spins. Such nonclassical reversal, which is absent from Landau-Lifshitz-Gilbert dynamics, is strikingly inhomogeneous across the FM chain, and it can be accompanied by reduction of the magnetization associated with localized spins, even to zero at specific locations. This feature arises because quantum STT generates a highly entangled nonequilibrium many-body state of all flowing and localized spins, despite starting from the initially unentangled ground state of a mundane FM. Furthermore, the mutual information between localized spins at the FM edges remains nonzero even at infinite separation as the signature of dynamical buildup of long-range entanglement. The growth in time of entanglement entropy differentiates between the quantum and conventional (i.e., noncollinear) setups for STT, reaching a much larger asymptotic value in the former case.},
doi = {10.1103/PhysRevX.11.021062},
journal = {Physical Review. X},
number = 2,
volume = 11,
place = {United States},
year = {Wed Jun 23 00:00:00 EDT 2021},
month = {Wed Jun 23 00:00:00 EDT 2021}
}

Works referenced in this record:

Excitation of a Magnetic Multilayer by an Electric Current
journal, May 1998


Quantum approach of mesoscopic magnet dynamics with spin transfer torque
journal, May 2013


Time-resolved measurement of spin-transfer-driven ferromagnetic resonance and spin torque in magnetic tunnel junctions
journal, February 2011

  • Wang, Chen; Cui, Yong-Tao; Katine, Jordan A.
  • Nature Physics, Vol. 7, Issue 6
  • DOI: 10.1038/nphys1928

Regional Versus Global Entanglement in Resonating-Valence-Bond States
journal, October 2007


Measurement of the spin-transfer-torque vector in magnetic tunnel junctions
journal, November 2007

  • Sankey, Jack C.; Cui, Yong-Tao; Sun, Jonathan Z.
  • Nature Physics, Vol. 4, Issue 1
  • DOI: 10.1038/nphys783

Quantitative measurement of voltage dependence of spin-transfer torque in MgO-based magnetic tunnel junctions
journal, November 2007

  • Kubota, Hitoshi; Fukushima, Akio; Yakushiji, Kay
  • Nature Physics, Vol. 4, Issue 1
  • DOI: 10.1038/nphys784

Spin transfer torques
journal, April 2008


Density-matrix algorithms for quantum renormalization groups
journal, October 1993


Theory of the magnetic polaron
journal, November 1981


First-principles calculation of spin-orbit torque in a Co/Pt bilayer
journal, January 2019


Real-Time Evolution Using the Density Matrix Renormalization Group
journal, August 2004


Quantum Simulation of Time-Dependent Hamiltonians and the Convenient Illusion of Hilbert Space
journal, April 2011


Density matrix formulation for quantum renormalization groups
journal, November 1992


Quantum Spin Torque Driven Transmutation of an Antiferromagnetic Mott Insulator
journal, May 2021


Current-Driven Magnetization Reversal and Spin-Wave Excitations in Co / Cu / Co Pillars
journal, April 2000


Resummation of the Holstein-Primakoff expansion and differential equation approach to operator square roots
journal, November 2020


Current-driven excitation of magnetic multilayers
journal, June 1996


Thermodynamic Limit of Density Matrix Renormalization
journal, November 1995


Nonequilibrium electron transport using the density matrix renormalization group method
journal, September 2004


The Density Matrix Renormalization Group and its time-dependent variants
conference, January 2011

  • Feiguin, Adrian E.; Avella, Adolfo; Mancini, Ferdinando
  • LECTURES ON THE PHYSICS OF STRONGLY CORRELATED SYSTEMS XV: Fifteenth Training Course in the Physics of Strongly Correlated Systems, AIP Conference Proceedings
  • DOI: 10.1063/1.3667323

Unbounded Growth of Entanglement in Models of Many-Body Localization
journal, July 2012


Current-Induced Switching of Domains in Magnetic Multilayer Devices
journal, August 1999


Measurement-Induced Phase Transitions in the Dynamics of Entanglement
journal, July 2019


Observation of magnons in Mn 2 Au films by inelastic Brillouin and Raman light scattering
journal, November 2017

  • Arana, M.; Estrada, F.; Maior, D. S.
  • Applied Physics Letters, Vol. 111, Issue 19
  • DOI: 10.1063/1.5001705

Spin transport through a spin- 1 2 XXZ chain contacted to fermionic leads
journal, June 2018


Quantum Spin Torque
journal, December 2017


Ultrafast dynamics of strongly correlated fermions—nonequilibrium Green functions and selfenergy approximations
journal, December 2019

  • Schlünzen, N.; Hermanns, S.; Scharnke, M.
  • Journal of Physics: Condensed Matter, Vol. 32, Issue 10
  • DOI: 10.1088/1361-648X/ab2d32

Emission of spin waves by a magnetic multilayer traversed by a current
journal, October 1996


Spin and Charge Pumping by a Steady or Pulse-Current-Driven Magnetic Domain Wall: A Self-Consistent Multiscale Time-Dependent Quantum-Classical Hybrid Approach
journal, November 2018


Quantum spin liquids
journal, January 2020


Many-body topological invariants from randomized measurements in synthetic quantum matter
journal, April 2020


Genuine quantum correlations in quantum many-body systems: a review of recent progress
journal, June 2018


First-principles study of spin-transfer torques in layered systems with noncollinear magnetization
journal, May 2008


The density-matrix renormalization group
journal, April 2005


Quantum spin transfer torque induced nonclassical magnetization dynamics and electron-magnetization entanglement
journal, March 2019


Probing Rényi entanglement entropy via randomized measurements
journal, April 2019


Multiscale modeling of current-induced switching in magnetic tunnel junctions using ab initio spin-transfer torques
journal, December 2017


Nonclassical Spin Transfer Effects in an Antiferromagnet
journal, January 2021


Energy and momentum conservation in spin transfer
journal, November 2020


Spin Transfer due to Quantum Magnetization Fluctuations
journal, December 2017


Possible contribution of high-energy magnons to unidirectional magnetoresistance in metallic bilayers
journal, May 2019


Inelastic electron-magnon interaction and spin transfer torque
journal, November 2008


Theory of atomistic simulation of spin-transfer torque in nanomagnets
journal, May 2013


Driving XXZ spin chains: Magnetic-field and boundary effects
journal, January 2019


Spin-torque building blocks
journal, December 2013

  • Locatelli, N.; Cros, V.; Grollier, J.
  • Nature Materials, Vol. 13, Issue 1
  • DOI: 10.1038/nmat3823

Geometric characterization of true quantum decoherence
journal, November 2015


Time-evolution methods for matrix-product states
journal, December 2019


Quantum entanglement in condensed matter systems
journal, August 2016


Current-induced macrospin versus spin-wave excitations in spin valves
journal, January 2006


Derivation of a time dependent Schrödinger equation as the quantum mechanical Landau–Lifshitz–Bloch equation
journal, August 2016


Spin-torque driven magnetization dynamics: Micromagnetic modeling
journal, April 2008


Manipulating quantum spins by spin-polarized current: an approach based upon $\mathcal{PT}$ -symmetric quantum mechanics
journal, March 2019

  • Bou Comas, Aleix; Chudnovsky, Eugene M.; Tejada, Javier
  • Journal of Physics: Condensed Matter, Vol. 31, Issue 19
  • DOI: 10.1088/1361-648X/ab0686

Mixed-State Entanglement from Local Randomized Measurements
journal, November 2020