Intensity relation between IR–UV doubly resonant sum-frequency spectra and antisymmetric resonant vibrational Raman scattering of chiral solutions

<div> <div> <p>Recent years have seen a huge progress in the development of phase sensitive second order laser spectroscopy which has proven to be a very powerful tool for the investigation of interfaces. These interferometric techniques involve the nonlinear interaction between three short laser pulses with the sample. In order to obtain accurate phase information, the relative phases between the pulses must be stabilized and their timings precisely controlled. Despite much progress made, fulfilling both requirements remains a formidable experimental challenge. The two common approaches employ different beam geometries which each yields its particular advantages and deficiencies. While non-collinear spectrometers allow for a relatively simple timing control they typically yield poor phase stability and require a challenging alignment. Collinear approaches in contrast come with a simplified alignment and improved phase stability but typically suffer from a highly limited timing control. In this contribution we present a general experimental solution which allows for combining the advantages of both approaches while being compatible with most of the common spectrometer types. Based on a collinear geometry we exploit different selected polarization states of the light pulses in well- defined places in the spectrometer to achieve a precise timing control. The combination of this technique with a balanced detection scheme al- lows for the acquisition of highly accurate phase resolved nonlinear spectra without any loss in experimental flexibility. In fact, we show that the implementation of this technique allows us to employ advanced pulse timing schemes inside the spectrometer, which can be used to sup- press nonlinear background signals and extend the capabilities of our spectrometer to measure phase resolved sum frequency spectra of inter- faces in a liquid cell.</p> </div> </div>

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Interpreting Vibrational Sum-Frequency Spectra of Sulfur Dioxide at the Air/Water Interface: A Comprehensive Molecular Dynamics Study

The Journal of Physical Chemistry B ◽

10.1021/jp100310s ◽

2010 ◽

Vol 114 (21) ◽

pp. 7245-7249 ◽

Cited By ~ 20

Author(s):

Marcel Baer ◽

Christopher J. Mundy ◽

Tsun-Mei Chang ◽

Fu-Ming Tao ◽

Liem X. Dang

Keyword(s):

Molecular Dynamics ◽

Sulfur Dioxide ◽

Water Interface ◽

Frequency Spectra ◽

Sum Frequency ◽

Air Water Interface

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Simultaneous Second-Harmonic, Sum-Frequency Generation and Stimulated Raman Scattering in MgO:PPLN

Materials ◽

10.3390/ma11112266 ◽

2018 ◽

Vol 11 (11) ◽

pp. 2266

Author(s):

Dismas Choge ◽

Huaixi Chen ◽

Lei Guo ◽

Guangwei Li ◽

Wanguo Liang

Keyword(s):

Raman Scattering ◽

Stimulated Raman Scattering ◽

Second Harmonic ◽

Sum Frequency Generation ◽

Laser Source ◽

Sum Frequency ◽

Wide Range ◽

Multi Wavelength ◽

Frequency Generation ◽

Stimulated Raman

In this study, simultaneous second-harmonic generation (SHG), sum frequency generation (SFG), and Raman conversion based on MgO-doped periodically poled lithium niobate (MgO:PPLN) for multi-wavelength generation is demonstrated. The approach used is based on a single MgO:PPLN crystal poled with a uniform period of 10.2 µm that phase matches SHG and SFG, simultaneously. Using a simplified double-pass geometry, up to 0.8 W of blue light at 487 nm is achieved by a frequency-doubling 974 nm laser diode pump, and 0.5 W of orange light at 598 nm is generated by frequency mixing 974 nm pump with C-band (1527–1565 nm) tunable laser source. At high pump powers of the 974 nm laser source, other unexpected peaks at 437, 536, 756, 815 and 1038 nm were observed, of which the 1038 nm line is due to Stimulated Raman Scattering within the MgO:PPLN crystal. The resulting multi-wavelength light source may find a wide range of applications in biomedicine and basic research.

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