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Djoufack ZI, Tala-Tebue E, Nguenang JP, Kenfack-Jiotsa A. Quantum soliton in 1D Heisenberg spin chains with Dzyaloshinsky-Moriya and next-nearest-neighbor interactions. CHAOS (WOODBURY, N.Y.) 2016; 26:103110. [PMID: 27802678 DOI: 10.1063/1.4965423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We report in this work, an analytical study of quantum soliton in 1D Heisenberg spin chains with Dzyaloshinsky-Moriya Interaction (DMI) and Next-Nearest-Neighbor Interactions (NNNI). By means of the time-dependent Hartree approximation and the semi-discrete multiple-scale method, the equation of motion for the single-boson wave function is reduced to the nonlinear Schrödinger equation. It comes from this present study that the spectrum of the frequencies increases, its periodicity changes, in the presence of NNNI. The antisymmetric feature of the DMI was probed from the dispersion curve while changing the sign of the parameter controlling it. Five regions were identified in the dispersion spectrum, when the NNNI are taken into account instead of three as in the opposite case. In each of these regions, the quantum model can exhibit quantum stationary localized and stable bright or dark soliton solutions. In each region, we could set up quantum localized n-boson Hartree states as well as the analytical expression of their energy level, respectively. The accuracy of the analytical studies is confirmed by the excellent agreement with the numerical calculations, and it certifies the stability of the stationary quantum localized solitons solutions exhibited in each region. In addition, we found that the intensity of the localization of quantum localized n-boson Hartree states increases when the NNNI are considered. We also realized that the intensity of Hartree n-boson states corresponding to quantum discrete soliton states depend on the wave vector.
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Affiliation(s)
- Z I Djoufack
- Department of Telecommunication and Network Engineering, Fotso Victor University Institute of Technology Fotso Victor, University of Dschang, P.O. Box 134, Bandjoun, Cameroon
| | - E Tala-Tebue
- Department of Telecommunication and Network Engineering, Fotso Victor University Institute of Technology Fotso Victor, University of Dschang, P.O. Box 134, Bandjoun, Cameroon
| | - J P Nguenang
- Fundamental Physics Laboratory, Group of Nonlinear Physics and Complex Systems, Department of Physics, University of Douala, P.O. Box 24157, Douala, Cameroon
| | - A Kenfack-Jiotsa
- Nonlinear Physics and Complex Systems Group, Department of Physics, The Higher Teachers' Training College, University of Yaounde I, P.O. Box 47, Yaounde, Cameroon
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Evangeline Rebecca T, Latha MM. Localized spin excitations in an antiferromagnetic spin system with D-M interaction. CHAOS (WOODBURY, N.Y.) 2016; 26:063116. [PMID: 27368781 DOI: 10.1063/1.4954266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The existence of localized spin excitations and spin deviations along the site in a one-dimensional antiferromagnet with Dzyaloshinski-Moriya (D-M) interaction has been studied using quasiclassical approximation. By introducing the Holstein-Primakoff bosonic representation of spin operators, the coherent state ansatz, and the time dependent variational principle, a discrete set of coupled nonlinear partial differential equations governing the dynamics is derived. Employing the multiple-scale method, one, two and three solitary wave solutions are constructed and depicted graphically.
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Affiliation(s)
| | - M M Latha
- Department of Physics, Women's Christian College, Nagercoil 629 001, India
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Tang B, Li DJ, Tang Y. Quantum breathers in Heisenberg ferromagnetic chains with Dzyaloshinsky-Moriya interaction. CHAOS (WOODBURY, N.Y.) 2014; 24:023113. [PMID: 24985427 DOI: 10.1063/1.4875041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We present an analytical study on quantum breathers in one-dimensional ferromagnetic XXZ chains with Dzyaloshinsky-Moriya interaction by means of the time-dependent Hartree approximation and the semidiscrete multiple-scale method. The stationary localized single-boson wave functions are obtained and these analytical solutions are checked by numerical simulations. With such stationary localized single-boson wave functions, we construct quantum breather states. Furthermore, the role of the Dzyaloshinsky-Moriya interaction is discussed.
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Affiliation(s)
- Bing Tang
- Department of Physics, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - De-Jun Li
- College of Physics, Mechanical and Electrical Engineering, Jishou University, Jishou 416000, People's Republic of China
| | - Yi Tang
- Department of Physics, Xiangtan University, Xiangtan 411105, People's Republic of China
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Sato M, Sievers AJ. Experimental and numerical exploration of intrinsic localized modes in an atomic lattice. J Biol Phys 2009; 35:57-72. [PMID: 19669569 DOI: 10.1007/s10867-009-9135-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2008] [Accepted: 11/26/2008] [Indexed: 11/25/2022] Open
Abstract
This review focuses attention on the experimental studies of intrinsic localized modes (ILMs) produced in driven atomic lattices. Production methods involve the application of modulational instability under carefully controlled conditions. One experimental approach is to drive the atomic lattice far from equilibrium to produce ILMs, the second is to apply a driver of only modest strength but nearby in frequency to a plane wave mode so that a slow transformation from large amplitude standing waves to ILMs takes place. Since, in either case, the number of ILMs produced is small, the experimental observation tool appropriate for this task is four-wave mixing. This nonlinear detection technique makes use of the nonlinearity associated with an ILM to enhance its signal over that produced by the more numerous, but linear, spin waves. The final topic deals with numerical simulations of a nonlinear nanoscale atomic lattice where the new feature is running ILMs.
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Affiliation(s)
- M Sato
- Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan.
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Cox S, McDonald RD, Armanious M, Sengupta P, Paduan-Filho A. Unusual magneto-optical phenomenon reveals low energy spin dispersion in the spin-1 anisotropic Heisenberg antiferromagnetic chain system NiCl2-4SC(NH2)_{2}. PHYSICAL REVIEW LETTERS 2008; 101:087602. [PMID: 18764662 DOI: 10.1103/physrevlett.101.087602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2008] [Indexed: 05/26/2023]
Abstract
Electron paramagnetic resonance measurements of NiCl2-4SC(NH2)_{2} reveal the low-energy spin dispersion, including a magnetic-field interval in which the two-magnon continuum is within k_{B}T of the ground state, allowing a continuum of excitations over a range of k states, rather than only the k=0 single-magnon excitations. This produces a novel Y shape in the frequency-field EPR spectrum measured at T > or = 1.5 K. Since the interchain coupling J_{ perpendicular}<<k_{B}T, this shape can be reproduced by a single S=1 antiferromagnetic Heisenberg chain with a strong easy-plane single-ion anisotropy. Importantly, the combination of experiment and modeling we report herein demonstrates a powerful approach to probing spin dispersion in a wide range of interacting magnetic systems without the stringent sample requirements and complications associated with inelastic scattering experiments.
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Affiliation(s)
- S Cox
- National High Magnetic Field Laboratory, Los Alamos National Laboratory, MS-E536, Los Alamos, New Mexico 87545, USA
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Zvyagin SA, Wosnitza J, Batista CD, Tsukamoto M, Kawashima N, Krzystek J, Zapf VS, Jaime M, Oliveira NF, Paduan-Filho A. Magnetic excitations in the spin-1 anisotropic Heisenberg antiferromagnetic chain system NiCl(2)-4SC(NH(2))(2). PHYSICAL REVIEW LETTERS 2007; 98:047205. [PMID: 17358808 DOI: 10.1103/physrevlett.98.047205] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2006] [Indexed: 05/14/2023]
Abstract
NiCl(2)-4SC(NH(2))(2) (DTN) is a quantum S=1 chain system with strong easy-pane anisotropy and a new candidate for the Bose-Einstein condensation of the spin degrees of freedom. ESR studies of magnetic excitations in DTN in fields up to 25 T are presented. Based on analysis of the single-magnon excitation mode in the high-field spin-polarized phase and previous experimental results [Phys. Rev. Lett. 96, 077204 (2006)10.1103/PhysRevLett.96.077204], a revised set of spin-Hamiltonian parameters is obtained. Our results yield D=8.9 K, J(c) = 2.2 K, and J(a,b) = 0.18 K for the anisotropy, intrachain, and interchain exchange interactions, respectively. These values are used to calculate the antiferromagnetic phase boundary, magnetization, and the frequency-field dependence of two-magnon bound-state excitations predicted by theory and observed in DTN for the first time. Excellent quantitative agreement with experimental data is obtained.
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Affiliation(s)
- S A Zvyagin
- Dresden High Magnetic Field Laboratory (HLD), Forschungszentrum Dresden-Rossendorf, 01314 Dresden, Germany
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Sato M, Hubbard BE, English LQ, Sievers AJ, Ilic B, Czaplewski DA, Craighead HG. Study of intrinsic localized vibrational modes in micromechanical oscillator arrays. CHAOS (WOODBURY, N.Y.) 2003; 13:702-715. [PMID: 12777135 DOI: 10.1063/1.1540771] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Intrinsic localized modes (ILMs) have been observed in micromechanical cantilever arrays, and their creation, locking, interaction, and relaxation dynamics in the presence of a driver have been studied. The micromechanical array is fabricated in a 300 nm thick silicon-nitride film on a silicon substrate, and consists of up to 248 cantilevers of two alternating lengths. To observe the ILMs in this experimental system a line-shaped laser beam is focused on the 1D cantilever array, and the reflected beam is captured with a fast charge coupled device camera. The array is driven near its highest frequency mode with a piezoelectric transducer. Numerical simulations of the nonlinear Klein-Gordon lattice have been carried out to assist with the detailed interpretation of the experimental results. These include pinning and locking of the ILMs when the driver is on, collisions between ILMs, low frequency excitation modes of the locked ILMs and their relaxation behavior after the driver is turned off.
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Affiliation(s)
- M Sato
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853-2501, USA
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