We present the studies of the interface optical phonons in k-component Fibonacci (KCF) dielectric multilyaers, in which k different incommensurate intervals are arranged according to a substitution rule. In the dielectric continuum approximation, the dispersion relations and the frequency spectra are obtained by the transfer-matrix method. Free-boundary and periodic-boundary conditions are taken into account. With the free-boundary condition, the dispersion relations of the interface optical phonons in the KCF multilayers are demonstrated to possess two bands of dual structures. For the KCF multilayers with (Formula presented) each subband is a self-similar structure and contains (Formula presented) filial generations; for the KCF multilayers with (Formula presented) the sub-bands do not show self-similarity, but they still have the hierarchical characteristic (where k is the number of different incommensurate intervals). In the case of the periodic-boundary condition, the frequency span of interface optical phonons in the KCF multilayers is singularly continuous and the frequency spectra are analyzed by a multifractal concept. A dimensional spectrum of singularities associated with the frequency spectrum, (Formula presented) demonstrates that in the KCF multilayers the interface optical phonons distribution presents a genuine multifractality. It is also shown that by increasing the number of different incommensurate intervals in KCF multilayers, the fractal dimension of the corresponding support decreases. © 1999 The American Physical Society.
Peng R. W.;Jin G. J.;Wang Mu;Hu A.;Jiang S. S.;Feng D.
Physical Review B Condensed Matter and Materials Physics
1999
SrBi
Li Aidong;Wu Di;Ling Huiqin;Yu Tao;Wang Mu;Yin Xiaobo;Liu Zhiguo;Ming Naiben
Journal of Applied Physics
2000
We study in this paper the diffraction spectrum (Fourier transform) of a one-dimensional k-component Fibonacci structure (KCFS), which contains k different intervals and can be generated by a substitution rule. Theoretical and numerical calculations based on the geometrical models for atomic KCFS have been made. The structures with 1
Peng R. W.;Wang Mu;Hu An;Jiang S. S.;Jin G. J.;Feng Duan
Physical Review B
1995
One excimer laser pulse through a silicon glass phase mask was used to directly generate periodic surface structures on top of a lithium niobate (LN) wafer. The surface corrugations have a period that is the same as that of the mask grating. Measurement of the grating coupler with a He-Ne laser beam coupling into the waveguide found three mode of incident lights transmitting into the waveguide.
Luo Gui peng;Wang Mu;Zhu Shi ning;Liu Zhi guo;Lu Yan qing;Chen Xiao yuan;Ge Chuan zhe;Ming Nai ben;Wu Hai ming;Lu Zhu hong
Pacific Rim Conference on Lasers and Electro Optics CLEO Technical Digest
1997
Oriented LiNbO
Wu Z. C.;Hu W. S.;Liu J. M.;Wang M.;Liu Z. G.
Materials Letters
1998
We report a new method for one-dimensional, self-organized, nanometer-sized crystalline silicon (nc-Si) dots growth through pulsed laser-induced melting followed by regrowth of a-Si:H films. A transient thermal grid was generated by a high energy KrF excimer laser through a phase shifting mask grating directly on the samples, leading to local phase transitions. The hemispherically shaped nc-Si dots with sizes of ∼200 nm in diameter and ∼20 nm in height were grown and self-organized along the lines of the grating. The microstructures and crystallinity of the nc-Si dots were determined using atomic force microscope images and cross-section transmission electron microscope photographs; and the growth mechanism of self-organized nc-Si dots is also discussed. © 1998 Elsevier Science B.V. All rights reserved.
Chen Kunji;Luo Guipeng;Wang Mingxiang;Gao Xiang;Xu Jun;Wang Mu;Huang Xinfan;Ming Naiben
Journal of Non Crystalline Solids
1998
The magnetic anisotropy of Ni thin films fabricated under different growth conditions have been studied by the ferromagnetic resonance (FMR) method. The FMR data have been fitted theoretically. The results show that the anisotropy is an orthorhombic anisotropy, and there exists an optimal rotary speed of the sample for a fixed deposition rate. Near the optimal speed, the anisotropy field along the in-plane easy axis exhibits a maximum, while the anisotropy field perpendicular to the film plane exhibits a minimum. The origin of orthorhombic anisotropy has been discussed. © 1998 Elsevier Science B.V. All rights reserved.
Kang S. S.;Liu X. Y.;Xiang X. H.;Jin G. J.;Du J. H.;Lu M.;Wang Mu;Sui Y. X.;Hu A.;Jiang S. S.;Feng D.;Feng J. W.;Xia H.
Journal of Magnetism and Magnetic Materials
1998
The dynamic behavior of the concentration field in crystallization is investigated by considering the coupling of the bulk concentration field and interfacial kinetics. It is shown that the concentration field may become unstable for perturbations with certain wavelength. When instability occurs, the physical environment in front of the growing interface will fluctuate and the interfacial growth mode will be affected accordingly. We suggest that our analysis can be used to interpret some spatial-temporal instabilities observed in crystallization. © 1999 The American Physical Society.
Wang Mu;Yin Xiao-Bo;Peng Ru-Wen;Ming Nai-Ben;Vekilov Peter G.
Physical Review E Statistical Physics Plasmas Fluids and Related Interdisciplinary Topics
1999
A series of Co
Xu Q. Y.;Chen H.;Sang H.;Yin X. B.;Ni G.;Lu J.;Wang M.;Du Y. W.
Journal of Magnetism and Magnetic Materials
1999
We present a study of electronic behaviours in the k-component Fibonacci (KCF) quantum waveguides, in which k different incommensurate intervals are arranged according to a substitution rule. On the basis of the transfer matrix method, the quantum transmission properties of the KCF stub structures are obtained. It is shown that the transmission coefficient depends on the wavevector of the electron and the number of different incommensurate intervals k. For the KCF waveguides with the same k, on increasing the number of stubs, the minima in transmission extend gradually into the band gap over which the transmission is blocked. Meanwhile more transmission peaks appear. For finite KCF stub structures, on increasing the number of different incommensurate intervals k, the total transmission over the spectral region of interest decreases gradually and the width of the electronic band gap is enlarged. Moreover, when the value of k is large enough, the transmission is basically shut off, except at a few energies where resonant tunnelling takes place. These properties make it possible to use this kind of KCF waveguide as a switching device for digital applications. On the other hand, the charge-density distributions in these structures are singularly continuous. We propose that they can be analysed using a multifractal concept. A dimensional spectrum of singularities associated with the charge density, f(α), demonstrates that the electronic transport in the KCF waveguide presents scaling properties; hence the charge-density distribution shows a genuine multifractality.
Peng R. W.;Jin G. J.;Wang Mu;Hu A.;Jiang S. S.;Feng D.
Journal of Physics Condensed Matter
2000