CONFERENCE PROCEEDINGS
Advanced Search
Home > Proceedings > Volume 8813 > Article
Open Access Paper
26 September 2013 A theory of quantum dynamics of a nanomagnet under excitation
L. J. Sham
Author Affiliations +
Proceedings Volume 8813, Spintronics VI; 88131Y (2013) https://doi.org/10.1117/12.2026564
Event: SPIE NanoScience + Engineering, 2013, San Diego, California, United States
Abstract
A quantum treatment of magnetization dynamics of a nanomagnet between a thousand and a million spins may be needed as the magnet interacts with quantum control. The advantage of the all-quantum approach over the classical treatment of magnetization is the accounting for the correlation between the magnet and the control agent and the first-principles source of noise. This supplement to the conference talk will concentrate on an overview of the theory with a presentation of the basic ideas which could have wide applications and illustrations with some results. Details of applications to specific models are or will be published elsewhere. A clear concept of the structure of the ground and excited macrospin states as magnetization rotation states and magnons in the Bloch/Dyson sense gives rise to a consistent theory of the magnetization dynamics of a ferromagnet modeled by the Heisenberg Hamiltonian. An example of quantum control is the spin torque transfer, treated here as a sequence of scatterings of each current electron with the localized electrons of the ferromagnet, yields in each encounter a probability distribution of the magnetization recoil state correlated with each outgoing state of the electron. This picture provides a natural Monte Carlo process for simulation of the dynamics in which the probability is determined by quantum mechanics. The computed results of mean motion, noise and damping of the magnetization will be discussed.
© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Citation Download Citation
L. J. Sham "A theory of quantum dynamics of a nanomagnet under excitation", Proc. SPIE 8813, Spintronics VI, 88131Y (26 September 2013); https://doi.org/10.1117/12.2026564
PROCEEDINGS
 11 PAGES
DOWNLOAD PAPER SAVE TO MY LIBRARY
GET CITATION
Lens.org Logo
CITATIONS
Cited by 1 scholarly publication.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Magnons
Scattering
Magnetism
Monte Carlo methods
Quantum physics
Anisotropy
Control systems
RELATED CONTENT
Subscribe to Digital Library
Receive Erratum Email Alert
Back to Top