Ultrafast Spectroscopy
Ultrafast spectroscopy is a specialized technique used to investigate the dynamics of molecular and atomic systems on extremely short timescales, typically ranging from femtoseconds (10^-15 seconds) to picoseconds (10^-12 seconds). Employing ultrashort laser pulses provides valuable insights into the transient behavior of materials and helps study processes such as electron and energy transfer, chemical reactions, and structural changes at the molecular level. Group Site
Hollow-Core Fiber Optical Broadening
This is the process of expanding the bandwidth of an ultrashort laser pulse using a special type of fiber optic. When the intense laser pulse propagates through this fiber, the light travels in the air-filled core rather than a solid material, which significantly reduces nonlinear effects and allows for the generation of extremely broadband spectra. This technique is particularly useful in ultrafast spectroscopy, as it enables the production of shorter laser pulses with a wide range of colors, facilitating the study of ultrafast phenomena at higher resolutions and time scales.
FPGAs as Oscilloscopes and Arbitrary Waveform Generators
Field-Programmable Gate Arrays (FPGAs) are versatile digital devices that can be used as both oscilloscopes and arbitrary waveform generators in certain applications. As oscilloscopes, FPGAs can process incoming analog signals and convert them into digital data in real-time. By leveraging their programmable nature, FPGAs can perform on-the-fly signal processing, enabling various functionalities such as signal triggering, waveform display, and measurements like frequency, amplitude, and rise times. This makes them suitable for capturing and analyzing fast and complex signals in electronic circuits, communication systems, and other fields.
On the other hand, FPGAs can also function as arbitrary waveform generators (AWGs). In this mode, the FPGA is programmed to generate precise and customizable waveforms with high speed and accuracy. By controlling the timing, amplitude, and shape of the generated signals, FPGAs can produce complex waveforms that match specific requirements for testing, signal simulation, or other experimental purposes. Their ability to generate waveforms with fine resolution and high repetition rates makes them valuable tools in research, development, and testing of electronic systems.
Creating a Rough Vacuum
A rough vacuum is a state of reduced pressure that lies between atmospheric pressure and high vacuum levels. In this context, PVC (polyvinyl chloride) pipes were utilized to fabricate a vacuum lining due to their air-tight sealing properties. By attaching a vacuum pump to the PVC chamber, air molecules are extracted, leading to a decrease in pressure within the chamber. In ultrafast spectroscopy, vacuums are employed to minimize the interference of air molecules with the ultrafast laser pulses and to reduce sample contamination. Additionally, the FPGA will be utizilized to act as a safety valve between stages: by having the FPGA continuously monitor the analog output of various pressure gauges, we can ensure that all components of the vacuum system can automatically seal if there is an anomaly (power outage, leak, etc.)