Design and Construction of an Efficient Atomization Tool for Strong Field Science at the Nanoscale
University of South Alabama
Mentored by Dr. Carlos Trallero
In order to better understand ultrafast light interaction with nanoparticles (such as Coulomb explosion), we must use a light source capable of resolving images at the nanoscale. Free Electron Lasers (such as the Linear Coherent Light Source at SLAC or the Free-Electron Laser in Hamburg at DESY) have the capability to produce femtosecond infrared (50 fs) and x-ray (10-100 fs) pulses and the temporal stability to to perform pump-probe experiments. These are indispensible tools for studying physics at the nanoscale where the size of the object is smaller than the diffraction limit of visible light. The team at Kansas State University has successfully preformed multiple prior beamtimes studying the interaction of intense IR laser pulse with dielectric SiO2 nanoparticles. However metallic nanoparticles have proven a challenge due to the inability to deliver a sufficient number of gas phase nanoparticles into the experiment.
In order to generate gas phase nanoparticles, an aqueous solution first must be atomized and coupled into the experiment. Commercial atomizers use the Bernoulli Effect to pull a large amount of nanoparticle solution into a cavity where a jet of pressured gas can blast away droplets to create an aerosol. Unfortunately, this violent process has a tendency to strip the ligand shell from more fragile, metallic nanoparticles, as well as produces aerosol with high waste in return. Over a 10 week period, we tested a new design for the atomizer, which implemented a double tube design to allow liquid to flow onto the gas jet and produce just enough aerosol to match the liquid provided, eliminating high waste production and leading to a gentle process that would not threaten the fragile ligand shell of metallic nanoparticles. Our novel design has proven successful at delivering a high density of nanoparticles while generating incredibly low amounts of waste. This has the potential to open up many new experimental avenues examining the effects of strong laser pulses on nanosystems.
Research Group: Adam Summers, Jeff Powell, Dr. Carlos Trallero, Derrek Wilson, Jan Tross, Georgios Kolliopoulos, Brandin Davis
Technical Staff: Andy Thurlow, Chris Aikens, Justin Millitte
Air Force Office of Scientific Research
Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy (DOE) under Grant No. DE-FG02-86ER13491