We report here an experimental setup to perform three-pulse pump-probe measurements over a wide wavelength and temperature range. By combining two pump pulses in the visible (650 nm-900 nm) and mid-IR (5 μm-20 μm) range, with a broadband supercontinuum white-light probe, our apparatus enables both the combined selective excitation of different material degrees of freedom and a full time-dependent reconstruction of the non-equilibrium dielectric function of the sample. We describe here the optical setup, the cryogenic sample environment, and the custom-made acquisition electronics capable of referenced single-pulse detection of broadband spectra at the maximum repetition rate of 50 kHz, achieving a sensitivity of the order of 10-4 over an integration time of 1 s. We demonstrate the performance of the setup by reporting data on a mid-IR pump, optical push, and broadband probe in a single crystal of Bi2Sr2Y0.08Ca0.92Cu2O8+δ across the superconducting and pseudogap phases.

中文翻译：

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可见泵-中红外泵-宽带探头：用于 50 kHz 单次超快光谱的三脉冲装置的开发和表征

我们在这里报告了一个实验装置，用于在很宽的波长和温度范围内执行三脉冲泵探头测量。通过将可见光 (650 nm-900 nm) 和中红外 (5 μm-20 μm) 范围内的两个泵浦脉冲与宽带超连续谱白光探针相结合，我们的设备能够对不同材料程度的组合选择性激发自由度和样品非平衡介电函数的全时间相关重建。我们在这里描述了光学设置、低温样品环境和定制的采集电子设备，能够以 50 kHz 的最大重复频率对宽带光谱进行参考单脉冲检测，在积分时间 1 s。我们通过报告中红外泵的数据来展示设置的性能，