Study of Intrinsic Localized Modes in Quantum Lattices

量子晶格中本征局域模式的研究

• 批准号: 18340086
• 负责人: SATO Masayuki
• 金额: $ 10.09万
• 依托单位: Kanazawa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18340086/
• 关键词: Intrinsic Localized Modes; Terahertz Spectroscopy; Far-infrared Spectroscopy; Four-wave Mixing Spectroscopy; Laser Spectroscopy; Lattice Vibration; Dielectric materials

A THz nonlinear four wave mixing spectrometer has been developed for studies of intrinsic localized modes of phonon vibration in solids. A FIR laser excited by a TEA laser, a CW FIR laser excited by a carbon dioxide gas laser, a titanium-sapphire laser, Fourier spectrometers have been modified, converted and upgraded. Those equipments have been operated.From theoretical consideration of the time-resolved four wave mixing spectroscopy using above lasers, it has been concluded that the frequency of the FIR laser has to be coincide with a n-th harmonics of a repetition frequency of the titanium-sapphire laser. A cavity length of the titanium sapphire laser must be adjusted to achieve the coincidence of those frequencies. The adjustment of the cavity length is estimated to be within 100mm, and the adjustment with such length will be possible. In this study, we haven't achieved a full development of the four-wave mixing spectrometer with synchronized FIR and titanium-sapphire lasers, partia … More lly because of this unexpected synchronizing problem and because of a failure of an excitation laser of the titanium laser. However, we have been expecting that the development will be completed and four-wave mixing spectra of solids will be measured. It is also expected that problems of phase transition phenomena of solids like dielectrics will be well studied from the point of view of the nonlinear intrinsic localized modes.Intrinsic localized modes based on a 3rd order nonlinearity have been experimentally observed in antiferromagnets and MEMS oscillators. Measurements of four wave-mixing spectra and discovery of sideband resonant structure are very powerful tools in those studies. In this study, we have speculated that the origin of the sideband resonant structure is the fact that the cross nonlinear resonant frequency shift is always larger than the auto nonlinear resonant frequency shift. We have also speculating that the same mechanism keeps the shape of such nonlinear localized modes. We have confirmed that similar sideband structure appears for the intrinsic localized modes based on a 2nd order nonlinearity, that is expected for lattice vibrations of solid lattices. Less

研制了一台太赫兹非线性四波混频谱仪，用于研究固体中声子振动的本征局域模。对TEA激光器激发的远红外激光器、二氧化碳气体激光器激发的连续远红外激光器、钛蓝宝石激光器、傅里叶光谱仪进行了改造、改装和升级。从理论上分析了利用上述激光器进行时间分辨四波混频光谱的可行性，得出了远红外激光器的频率必须与钛宝石激光器重复频率的n次谐波相一致的结论。必须调整钛蓝宝石激光器的腔长以实现这些频率的重合。腔体长度的调整估计在100mm以内，并且将有可能以这样的长度进行调整。在这项研究中，我们还没有实现四波混频光谱仪与同步FIR和钛蓝宝石激光器的全面发展，部分， ...更多信息 这仅仅是因为该意外的同步问题以及因为钛激光器的激发激光器的故障。然而，我们一直期待着发展将完成和四波混合光谱的固体将被测量。基于三阶非线性的本征局域模已在反铁磁体和MEMS振荡器中被实验观测到。四波混频谱的测量和边带共振结构的发现是这些研究的有力工具。在这项研究中，我们推测边带谐振结构的起源是交叉非线性谐振频移总是大于自非线性谐振频移的事实。我们还推测，同样的机制保持这种非线性局域模的形状。我们已经证实，类似的边带结构出现的基础上的二阶非线性，这是预期的固体晶格的晶格振动的固有局域模式。少

项目成果

Mobile localized excitations in the acoustic spectrum of a nonlinear micromechanical cantilever array

非线性微机械悬臂阵列声谱中的移动局部激励

• 发表时间: 2007
• 期刊: Phys. Rev. Lett 98
• 作者: H. Ueba;B. N. J. Persson;M.Sato and A.J. Sievers
• 通讯作者: M.Sato and A.J. Sievers

Visualization intrinsic localized modes with a nonlinear micromechani cal array

使用非线性微机械阵列可视化固有局部模式

• 发表时间: 2008
• 期刊: Low Temperature Physics(Fizika Nizkih Temper atur) 34
• 作者: M. Sato;A. J. Sievers
• 通讯作者: A. J. Sievers

Management of localized energy in discrete nonlinear transmission lin es

离散非线性传输线中的局部能量管理

• 发表时间: 2007
• 期刊: EuroPhysics Letters 80
• 作者: M. Sato;S. Yasui;M. Kimura;T. Hikihara;A. J. Sievers
• 通讯作者: A. J. Sievers

Nonlinear Four-wave mixing Spectrometer in THz region

太赫兹区域非线性四波混频光谱仪

• 发表时间: 2008
• 作者: Seri Yamaguchi;Takako Yoshiike;Masayuki Sato
• 通讯作者: Masayuki Sato

Visualization intrinsic localized modes with anonlinear micromechanical array

非线性微机械阵列的可视化固有局部模式

• 发表时间: 2008
• 期刊: Low Temperature Physics (Fizika Nizkih Temperatur) 34
• 作者: M. Sato;A. J. Sievers
• 通讯作者: A. J. Sievers