Anisotropy and Dzyaloshinsky- Moriya Interaction in V15 Manabu Machida, Seiji Miyashita, and Toshiaki Iitaka IIS, U. Tokyo Dept. of Physics, U. Tokyo RIKEN.

Slides:

Advertisements

Similar presentations

APRIL 2010 AARHUS UNIVERSITY Simulation of probed quantum many body systems.

Advertisements

MR TRACKING METHODS Dr. Dan Gamliel, Dept. of Medical Physics,

Thus in the rotating frame the magnetic field becomes time-independent while the z-magnetic field component is reduced by the frequency of rotation x RoF.

Spin-orbit effects in semiconductor quantum dots Departament de Física, Universitat de les Illes Balears Institut Mediterrani d’Estudis Avançats IMEDEA.

Chaos and interactions in nano-size metallic grains: the competition between superconductivity and ferromagnetism Yoram Alhassid (Yale) Introduction Universal.

Frequency Dependence of Quantum Localization in a Periodically Driven System Manabu Machida, Keiji Saito, and Seiji Miyashita Department of Applied Physics,

Numerical study on ESR of V15 IIS, U. Tokyo, Manabu Machida RIKEN, Toshiaki Iitaka Dept. of Phys., Seiji Miyashita June 27- July 1, 2005 Trieste, Italy.

Physics 452 Quantum mechanics II Winter 2011 Karine Chesnel.

UNIVERSITY OF NOTRE DAME Xiangning Luo EE 698A Department of Electrical Engineering, University of Notre Dame Superconducting Devices for Quantum Computation.

3.2.2 Magnetic Field in general direction Larmor frequencies: Hamiltonian: In matrix representation 

ESR Intensity and Anisotropy of Nanoscale Molecular Magnet V15 IIS, U. Tokyo, Manabu Machida RIKEN, Toshiaki Iitaka Dept. of Phys., Seiji Miyashita Fa3-4.

P460 - Spin1 Spin and Magnetic Moments (skip sect. 10-3) Orbital and intrinsic (spin) angular momentum produce magnetic moments coupling between moments.

Tony Hyun Kim (Partner: Connor McEntee) 11/17/ MW2-5 Prof. Roland.

Magnetic properties of a frustrated nickel cluster with a butterfly structure Introduction Crystal structure Magnetic susceptibility High field magnetization.

Determination of Spin-Lattice Relaxation Time using 13C NMR

Boltzmann Distribution and Helmholtz Free Energy

MSEG 803 Equilibria in Material Systems 6: Phase space and microstates Prof. Juejun (JJ) Hu

Reversing chaos Boris Fine Skolkovo Institute of Science and Technology University of Heidelberg.

F.F. Assaad. MPI-Stuttgart. Universität-Stuttgart Numerical approaches to the correlated electron problem: Quantum Monte Carlo.  The Monte.

Progress Towards the Accurate Calculation of Anharmonic Vibrational States of Fluxional Molecules and Clusters Without a Potential Energy Surface Andrew.

Laser-microwave double resonance method in superfluid helium for the measurement of nuclear moments Takeshi Furukawa Department of Physics, Graduate School.

Single-ion and exchange anisotropy effects in small single-molecule magnets* Richard A. Klemm University of Central Florida, Orlando, FL USA and Dmitri.

A. Krawiecki , A. Sukiennicki

Vector coupling of angular momentum. Total Angular Momentum L, L z, S, S z J and J z are quantized Orbital angular momentumSpin angular momentum Total.

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY Basics of …….. NMR phenomenonNMR phenomenon Chemical shiftChemical shift Spin-spin splittingSpin-spin splitting.

Magnetization dynamics

Ch ; Lecture 26 – Quantum description of absorption.

Complexity in Transition-Metal Oxides and Related Compounds A. Moreo and E. Dagotto Univ. of Tennessee, Knoxville (on leave from FSU, Tallahassee) NSF-DMR

1 Spin-triplet molecule inside carbon nanotube Bogdanova D.A., S.S.Moliver State University Ulyanovsk, Russia Grant-in-aid from Rus. Basic.

Electron behaviour in three-dimensional collisionless magnetic reconnection A. Perona 1, D. Borgogno 2, D. Grasso 2,3 1 CFSA, Department of Physics, University.

5. Formulation of Quantum Statistics

Drude weight and optical conductivity of doped graphene Giovanni Vignale, University of Missouri-Columbia, DMR The frequency of long wavelength.

Quantum response in dissipative environments University of Tokyo S. Miyashita 5 Nov Linear Response 50 Equilibrium & NE response collaborators: Akira.

Electron Spin Resonance and Quantum Dynamics Masaki Oshikawa (ISSP, University of Tokyo)

Microscopic origin of the adiabatic change of the magnetization Hans De Raedt Applied Physics-Computational Physics, Materials Science Centre, University.

Introduction to Molecular Magnets Jason T. Haraldsen Advanced Solid State II 4/17/2007.

13. Extended Ensemble Methods. Slow Dynamics at First- Order Phase Transition At first-order phase transition, the longest time scale is controlled by.

Nonlinear optical effect in the soft x-ray region by two-photon ionization of He + Nonlinear optical effect in the soft x-ray region by two-photon ionization.

DMITRY G. MELNIK AND TERRY A. MILLER The Ohio State University, Dept. of Chemistry, Laser Spectroscopy Facility, 120 W. 18th Avenue, Columbus, Ohio

Quasi-1D antiferromagnets in a magnetic field a DMRG study Institute of Theoretical Physics University of Lausanne Switzerland G. Fath.

Helical Spin Order in SrFeO 3 and BaFeO 3 Zhi Li Yukawa Institute for Theoretical Physics (YITP) Collaborator: Robert Laskowski (Vienna Univ.) Toshiaki.

Lanczos Representation Methods in Application to Rovibrational Spectroscopy Calculations Hong Zhang and Sean Smith Quantum & Molecular Dynamics Group Center.

M. Ueda, T. Yamasaki, and S. Maegawa Kyoto University Magnetic resonance of Fe8 at low temperatures in the transverse field.

Slow Dynamics of Magnetic Nanoparticle Systems: Memory effects P. E. Jönsson, M. Sasaki and H. Takayama ISSP, Tokyo University Co-workers: H. Mamiya and.

@ 15/7/2003 Tokyo Institute of Technology 1 Propagating beliefs in spin- glass models Yoshiyuki Kabashima Dept. of Compt. Intel. & Syst.

Recall that the proton precession magnetometer makes measurements of the total field, not the vector components of the field. Recall also that the total.

Chapter 4 Two-Level Systems, Spin. Two-level systems Let us start with the simplest non-trivial state space, with only two dimensions Despite its simplicity,

NMR study of a mixed-metal molecular magnet Yutaka FUJII (University of Fukui) Contents  Introduction (Magnetic properties)  Experimental results  1.

Photoinduced nano and micron structures K. Nasu Solid state theory division, Institute of materials structure science, High energy accelerator research.

NMR Studies of nanoscale molecular magnets Y. Furukawa Y. Fujiyoshi S. Kawakami K. Kumagai F. Borsa P. Kogerler Hokkaido University (Japan) Pavia University.

Dynamics of novel molecular magnets V-ring and rare earth compounds Okayama Univ. H. Nojiri Introduction Magnetization step in V-rectangular ring Short.

The University of Tokyo Seiji Miyashita

QUANTUM TRANSITIONS WITHIN THE FUNCTIONAL INTEGRATION REAL FUNCTIONAL

q Magnetic Field in general direction Larmor frequencies:

Stationary Perturbation Theory And Its Applications

Spin and Magnetic Moments (skip sect. 10-3)

Magnetic Susceptibility

with Masaki Oshikawa (UBC-Tokyo Institute of Technology)

Strong Coupling of a Spin Ensemble to a Superconducting Resonator

Alternating Antisymmetric Interaction in Nanoscale Iron Ring

Chapter 4 Two-Level Systems.

Kondo effect Him Hoang

Quantum mechanics II Winter 2012

Quantum tunneling by Hyperfine interaction Origin of adiabatic change of the magnetization and the symmetry of the molecules Seiji Miyashita, Hans de.

Choose all of the following observables for which it will be convenient to use the coupled representation to find the probabilities of different outcomes.

Spin-triplet molecule inside carbon nanotube

QM2 Concept Test 11.1 In a 3D Hilbert space,

郑公平河南师范大学第五届全国冷原子物理和量子信息青年学者学术讨论会

Hiroyuki Nojiri, Department of Physics, Okayama University

Ab initio calculation of magnetic exchange parameters

Presentation transcript:

Anisotropy and Dzyaloshinsky- Moriya Interaction in V15 Manabu Machida, Seiji Miyashita, and Toshiaki Iitaka IIS, U. Tokyo Dept. of Physics, U. Tokyo RIKEN

V15 Vanadiums provide fifteen 1/2 spins. Recently nano-magnets have attracted a lot of attention. Among them, we study the ESR of V15. [I. Chiorescu et al. (2000)]

Hamiltonian J=800K J2 J1

Electron Spin Resonance Energy absorptionis calculated by means of the Kubo formula. Double Chebyshev Expansion Method Subspace Iteration Method

Double Chebyshev Expansion Method (DCEM) The DCEM makes it possible to obtain the ESR intensity of V15 at arbitrary temperatures. Especially the DCEM has an advantage at high temperatures and strong fields.

Kubo Formula Intensity (total absorption): Energy absorption: Dynamical susceptibility:

Algorithm Trace Chebyshev polynomial expansion Time evolution Random vectors Leap-frog method ( Boltzmann-weighted time-dependent method ) Chebyshev expansion (Double Chebysev expansion method) Chebyshev expansion method also in time domain

Chebyshev vs Leap-frog >> 1000(T)100(T)10(T) Chebyshev 126(min) 187(min) 430(min) Leap-frog 11(min) 165(min)1326(min)

Test Parameters for DCEM J=800K, J1=54.4K, J2=160K DM interaction: D=(40K,40K,40K)

Temperature Dependence of Intensity [Y.Ajiro et al. (2003)]

With and Without DM 32K

Subpeak due to DM

Subspace Iteration Method (SIM) Much more powerful than the naïve power method. Especially the SIM has an advantage at low temperatures.

Method of Diagonalization Combination of (a)Anomalous Quantum Dynamics (Comp.Phys.Comm. Mitsutake et al. 1995) amplifies the eigenstates En Δ ｔ＞１ (b)Subspace Iteration Method (F.Chatelin1988) updates the orthogonal basis sets of low energy subspace S of the total Hilbert space.

Subspace and DOS S8 S56 Subspace S152

Energy Levels (DM=0,DD=0) (DM=40K,DD=0) (DM=0,DD≠0) (DM=40K,DD≠0) Energy (K)

Method of Moments (1) Probability function Moments

Total intensity Line width Method of Moments (2)

Test Parameters for SIM J1=250K, J2=350K DM interaction: D=(40K,40K,40K)

Line Width with DM/DD DM interaction -> Line width diverges!

at T=0.5K Larmor precession Peaks due to DM interaction

at T=32K Larmor precession Peaks due to DM interaction

at T=64K Larmor precession Peaks due to DM interaction

at T=128K Larmor precession Peaks due to DM interaction

at T=256K Larmor precession Peaks due to DM interaction

Summary The DCEM reproduces the experimentally obtained temperature dependence of the intensity. The DM interaction allows a transition between excited states that is otherwise forbidden. Measuring these ESR peaks at higher temperatures may provide a method of estimating the magnitude and direction of the DM interaction.