Welcome to the John C. Wright research group’s web page. Our group does laser spectroscopy. We use the narrow frequency distribution of tunable laser sources to gain spectral selectivity in an analytical measurement. We believe that there is a new family of high resolution spectroscopies based on multiresonant nonlinear spectroscopies that is particularly selective. These new methods are analogous to multidimensional NMR methods that are commonly used for structure determination in complex molecules.
The basic idea is that tuning several lasers to multiple resonances results in light signals at new frequencies that are combinations of the frequencies of the individual resonances, if those resonances are coupled to each other. States are coupled when excitation of one state results in a perturbation of another state because of intra- or intermolecular interactions between the states. By measuring the output light signal as a function of the frequencies of the input laser frequencies, a multidimensional spectrum can be defined where the diagonal peaks are the frequencies of individual states and the off-diagonal cross-peaks define which states are coupled. This new form of spectroscopy has important implications for analytical measurements because it provides the capability for "dissecting spectra."
Excitation of one spectral line will selectively enhance the other transitions in the spectrum that are coupled to the excited transition. Our group is developing the fundamental, experimental, and theoretical framework for this new family of analytical spectroscopies. The most promising applications use vibrational states so one can perform multidimensional vibrational spectroscopy. We have named these methods Doubly Vibrationally Enhanced (DOVE) and Triply Vibrationally Enhanced (TRIVE) Four Wave Mixing (FWM) Spectroscopies.
What is nonlinear spectroscopy? To learn more about the basic fundamentals of nonlinear spectroscopy, visit the fundamentals, non-linear spectroscopies, and coherent multidimensional spectroscopy pages. How do you do nonlinear spectroscopy? To learn more about the experimental details, visit our techniques section.
As for ourselves, you may learn more about the group's members, both past and present. The group publications, including past research topics, are also included. Finally, we have compiled a list of all important links to other research pages in non-linear (and some linear) spectroscopy.
Our work has been supported by the National Science Foundation under grant CHE-0650431.
This site is new and still developing. We appreciate your patience as aesthetics are forged and kinks are removed.
Updated: May 22nd, 2008.
Contact the webmaster at sblock@chem.wisc.edu