Carlos E. Nogales Herrera

Carlos saw his very first ray of light in Ibarra, a northern city in Ecuador. Certainly, he couldn’t say his interest in science started that day, but he grew up with more questions than answers that his hometown could provide. He physically left his town when he was sixteen. Somehow, he graduated as a physicist (Cum Laude), and lasers came across his life, changing it forever. The mysterious powers of light to analyze and explore nature called his attention, ending up developing what some people nowadays call 'interdisciplinary interests.' So, after playing with nanoparticles to enhance laser-based analytical techniques, he spent a year in the Down Under learning the ropes of laser development. Now, he is getting into the Analytical Chemistry Universe. As a Ph.D. student in the JTS group at RPI, is working hard to put everything together and, at some point, put his two cents in the immense ocean of human knowledge.

Broadly speaking, his research interests are in analytical analysis and instrumentation. From exploring and improving the basics on top of what the methods are developed, passing through the fusion, refinement, or creation of new methods, to the development and miniaturization of the instruments.

Nanoparticle-Enhanced Laser-Induced Breakdown Spectroscopy, NELIBS, is the very first topic he approached. LIBS is a technique well known for its capabilities for in-situ and fast real-time analysis. NELIBS is an improvement of LIBS where nanoparticles are used to increase the intensity of the signal received from the plasma. This increase comes from the effect of the extra electromagnetic fields from the plasmons in the nanoparticles, which also act like antennas transmitting the EM field from the laser. However, the variability of the signal between (in principle ceteris paribus) shots challenges its quantitative use. An exploration among more than 500 million spectral points within 600 combinations of variables (laser spot, fluence, nanoparticle size, etc.) in the interparticle distance limit, where only one field contributor is expected from the plasmon resonances, was carried out as an undergraduate research project.

Currently, at JTS labs, the final path of their research is still under construction. However, the combination of different tools and methods such as optical tweezers for opaque particles, laser-induced plasma spectroscopy, and mass spectrometry are starting to be explored to combine their analytical capabilities. Chromatography, femtosecond laser filaments as part of analytical systems, and miniaturization of the instrumentation are also of high interest and under consideration.