The transient absorption (TA) experiment allows quantitative characterization of time-dependent absorption of an optically excited sample. Two light pulses are required: femtosecond narrow-bandwidth pump pulse to excite the sample and delayed broad-bandwidth probe pulse to measure the changes in sample transmittance. The resulting difference absorption signal is measured as a function of the probe wavelength and the temporal delay between the pump and probe pulses.
The TA spectrum is much more elaborate than, e.g., a steady-state absorption or fluorescence decay spectrum. It provides information not only on the excited states of the system but also on all the intermediate evolutionary transients and non-emissive states both on the ground and the excited states.
HARPIA-TA can be equipped with a microscopy module HARPIA-MM, enabling spatially-resolved pump-probe measurements with a spatial resolution down to 5 μm. The HARPIA-MM module features a brightfield mode to observe the sample and determine the pump-probe spot location and transmission and reflection modes to carry out the pump-probe measurements.
- 最低至 2 μm 空间分辨率
- 可选配宽带宽和单色探测光
- 电控 XYZ 轴样品台
- 透射、镜面反射、漫反射几何光学设置
- 行业领先的灵敏度
- 330 nm – 24 µm 光谱范围
- 探测光延迟范围 2 ns – 8 ns
- 泵浦能量低至nJ级别
- 低温恒温器和蠕动泵支架
- 100 fs – 20 ps 连续可调脉宽
- 最大单脉冲能量 4 mJ
- 最高输出功率 20 W
- 单脉冲 – 1 MHz 重复频率
- BiBurst 脉冲串功能
- 自动谐波发生器（高达 5 次谐波）
- 190 fs – 20 ps 连续可调脉宽
- 最大单脉冲能量 2 mJ
- 最大输出功率 80 W
- 单脉冲 – 2 MHz 重复频率
- 脉冲选择器功能，可按需输出脉冲
- BiBurst 脉冲串模式
- 风冷型号
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