Advances in Hands-Off Femtosecond Parametric Amplifiers for Solid-State Materials Investigation

Time-resolved and static nonlinear optics (NLO) experiments at surface and bulk of advanced solid-state materials require agile femtosecond and picosecond tunable sources with high peak power and excellent stability. Repetition rate agility, ease of use and a compact footprint enhance experimental productivity and eliminate the need for an “expert” laser user. Typical experimental set-ups for study of interfaces and bulk material properties on meso- and nanoscale include two-dimensional infrared (2D-IR)¹, sum- frequency generation (SFG) ^{2, 3}, as well as transient absorption (TA)⁴ spectroscopy. Until recently, these experiments required titanium-sapphire amplifiers with repetition rates of 1-5 kHz, or mode-locked lasers at 80 MHz with limited energy and tuning ranges.&lt;!--![endif]----&gt;<br/>&lt;!--[endif]----&gt;With technological advancements provided by flexible Yb-based regenerative amplifiers, experiments can now be realized at 100 kHz-1 MHz repetition rates with significant improvements in signal-to-noise ratio^1,5. While for most experiments on solid-state samples, laser pulse energies in the microjoule range are perfectly adequate, some other benefits from higher energies that are now achievable in the latest generation of Yb amplifiers. After briefly describing recent advances in amplifiers, we will describe state-of-the-art tunable parametric amplifiers ranging from 190 nm to 16000 nm, allowing seamless access to most of the chemically relevant frequencies of interest^6-8. We will provide application examples that benefit from technological improvements including sealed, hands-off configurations, enhanced efficiency and short pulse generation.<br/> <br/><u>References:</u><br/>1. Farrell, K. M.; Ostrander, J. S.; Jones, A. C.; Yakami, B. R.; Dicke, S. S.; Middleton, C. T.; Hamm, P.; Zanni, M. T., <i>Opt. Express </i><b>2020,</b> <i>28</i> (22).<br/>2. Golbek, T. W.; Weidner, T., <i>The Journal of Physical Chemistry Letters </i><b>2023,</b> <i>14</i> (44).<br/>3. Lackner, M.; Hille, M.; Hasselbrink, E., <i>The Journal of Physical Chemistry Letters </i><b>2020,</b> <i>11</i> (1).<br/>4. Blaszczyk, O.; Krishnan Jagadamma, L.; Ruseckas, A.; Sajjad, M. T.; Zhang, Y.; Samuel, I. D. W., <i>Materials Horizons </i><b>2020,</b> <i>7</i> (3).<br/>5. Donaldson, P. M.; Greetham, G. M.; Middleton, C. T.; Luther, B. M.; Zanni, M. T.; Hamm, P.; Krummel, A. T., <i>Acc. Chem. Res. </i><b>2023,</b> <i>56</i> (15).<br/>6. Backus, E. H. G.; Schaefer, J.; Bonn, M., <i>Angewandte Chemie-International Edition </i><b>2020,</b> (59),.<br/>7. Chattopadhyay, A.; Boxer, S. G., <b>1995,</b> <i>117</i> (4).<br/>8. Wang, Z.; Morales-Acosta, M. D.; Li, S.; Liu, W.; Kanai, T.; Liu, Y.; Chen, Y.-N.; Walker, F. J.; Ahn, C. H.; Leblanc, R. M.; Yan, E. C. Y., <i>Chem. Commun. </i><b>2016,</b> <i>52</i> (14),.<br/>&lt;!--![endif]----&gt;