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arXiv · 1608.03503

A Versatile Setup for Ultrafast Broadband Optical Spectroscopy of Coherent Collective Modes in Strongly Correlated Quantum Systems

Edoardo Baldini·Andreas Mann·Simone Borroni·Christopher Arrell·Frank van Mourik·Fabrizio Carbone
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Abstract

A femtosecond pump-probe setup is described that is optimised for broadband transient reflectivity experiments on solid samples over a wide range of temperatures. By combining a temporal resolution of 45 fs and a broad detection range between 1.75 and 2.85 eV, this apparatus can provide insightful information on the interplay between coherent collective modes and high-energy electronic excitations, which is one of the distinctive characteristics of strongly interacting and correlated quantum systems. The use of a single-shot readout CMOS array detector at frame rates up to 10 kHz allows to resolve coherent oscillations with amplitudes below 10$^{-4}$ in $\Delta$R/R. We demonstrate the operation of this setup on the prototypical charge-transfer insulator La$_2$CuO$_4$, revealing the presence of coherent optical phonons with frequencies as high as 13 THz.

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Edoardo Baldini, Andreas Mann, Simone Borroni, Christopher Arrell, Frank van Mourik, Fabrizio Carbone. 2016-08-11. A Versatile Setup for Ultrafast Broadband Optical Spectroscopy of Coherent Collective Modes in Strongly Correlated Quantum Systems. https://arxiv.org/abs/1608.03503

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