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تسجيل مستخدم جديدTemperature dependent Raman study of phonons of different symmetries in single crystal Bi2Se3
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High quality single crystals of Bi2Se3 were grown using a modified Bridgman technique, the detailed study were carried out using Raman spectroscopy and characterized by Laue diffraction and high resolution transmission electron microscopy. Polarized Raman scattering measurements were also carried out, and both the A1g and A2g phonon modes showed strong polarization effect, which is consistent with the theoretical prediction. The temperature dependent study (in the temperature range 83 K to 523 K of Raman active modes were reported and observed to follow a systematic red shift. The frequency of these phonon modes are found to vary linearly with temperature and can be explained by first order temperature co-efficient. The temperature co-efficient for A11g, E2g and A21g modes were estimated to be -1.44*10-2, -1.94*10-2 and -1.95*10-2cm-1/K respectively.
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