Berweger Samuel, Neacsu Catalin C, Mao Yuanbing, Zhou Hongjun, Wong Stanislaus S, Raschke Markus B
Department of Chemistry and Department of Physics, University of Washington, Seattle, WA 98195, USA.
Nat Nanotechnol. 2009 Aug;4(8):496-9. doi: 10.1038/nnano.2009.190. Epub 2009 Jul 26.
Conventional phonon Raman spectroscopy is a powerful experimental technique for the study of crystalline solids that allows crystallography, phase and domain identification on length scales down to approximately 1 microm. Here we demonstrate the extension of tip-enhanced Raman spectroscopy to optical crystallography on the nanoscale by identifying intrinsic ferroelectric domains of individual BaTiO(3) nanocrystals through selective probing of different transverse optical phonon modes in the system. The technique is generally applicable for most crystal classes, and for example, structural inhomogeneities, phase transitions, ferroic order and related finite-size effects occurring on nanometre length scales can be studied with simultaneous symmetry selectivity, nanoscale sensitivity and chemical specificity.
传统的声子拉曼光谱是研究晶体固体的一种强大实验技术，它能够在低至约1微米的长度尺度上进行晶体学、相和畴的识别。在这里，我们通过选择性探测系统中不同的横向光学声子模式，识别单个钛酸钡（BaTiO₃）纳米晶体的本征铁电畴，从而证明了将针尖增强拉曼光谱扩展到纳米尺度的光学晶体学。该技术通常适用于大多数晶体类别，例如，可以通过同时具备的对称性选择性、纳米尺度灵敏度和化学特异性来研究纳米长度尺度上发生的结构不均匀性、相变、铁性有序和相关的有限尺寸效应。
