Surface optical phonons in gallium phosphide nanowires

2019-12-24 11:18:04

peak surface So nanowires phonons

责任者: Gupta, R.;Xiong, Q.;Mahan, G.D.;Eklund, P.C. 单位: Dept. of Phys., Pennsylvania State Univ., University Park, PA, USA 来源出处: Nano Letters(Nano Lett. (USA)),2003/12/,3(12):1745-50 摘要: Raman scattering studies of crystalline GaP nanowires reveal a strong additional peak in the first order spectrum that can be clearly assigned to surface optical (SO) phonons. The frequency of this SO peak is found to be sensitive to the dielectric constant of the surrounding medium in which the nanowire is embedded. A theory for the SO phonons in cylindrical wires is presented, the SO mode dispersion ω(q) and the experimental peak frequency are then used to predict the wavelength of the dominant Fourier component of the surface potential responsible for activating the SO mode. Interestingly, this SO phonon wavelength is found to agree with the wavelength of diameter modulation observed for some nanowires 关键词: gallium compounds;III-V semiconductors;nanowires;permittivity;Raman spectra;surface phonons;surface potential;surface optical phonons;gallium phosphide nanowires;Raman scattering;crystalline nanowires;first order spectrum;dielectric constant;cylindrical wires;mode dispersion;experimental peak frequency;dominant Fourier component;surface potential;phonon wavelength;diameter modulation;GaP