تقرير
Spectral narrowing of a phonon resonance in time-domain sum-frequency spectroscopy
| العنوان: | Spectral narrowing of a phonon resonance in time-domain sum-frequency spectroscopy |
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| المؤلفون: | Kiessling, Riko, Wolf, Martin, Paarmann, Alexander |
| سنة النشر: | 2022 |
| المجموعة: | Condensed Matter Physics (Other) |
| مصطلحات موضوعية: | Condensed Matter - Materials Science, Physics - Optics |
| الوصف: | Sum-frequency generation (SFG) spectroscopy provides a versatile method for the investigation of non-centrosymmetric media and interfaces. Here, using tunable picosecond infrared (IR) pulses from a free-electron laser, the nonlinear optical response of 4H-SiC, a common polytype of silicon carbide, has been probed in the frequency- and time-domain by infrared-visible vibrational SFG spectroscopy. In the SFG spectra we observe a sharp resonance near the longitudinal optical phonon frequency, arising from linear optical effects due the epsilon-near-zero regime of the IR permittivity. In the time domain, the build-up of the SFG intensity is linked to the free-induction decay of the induced coherent IR polarization. When approaching the frequency of the phonon resonance, a slower polarization dephasing is observed as compared to off-resonant IR excitation. Thus, by introducing a temporal delay between the IR and the visible up-conversion pulse we are able to demonstrate spectral narrowing of the phonon SFG resonance, as corroborated by model calculations. Comment: 11 pages, 7 figures |
| نوع الوثيقة: | Working Paper |
| URL الوصول: | http://arxiv.org/abs/2211.04593 |
| رقم الأكسشن: | edsarx.2211.04593 |
| قاعدة البيانات: | arXiv |
| الوصف غير متاح. |