With this award from the Chemistry Major Research Instrumentation (MRI) Program that is co-funded by the Chemistry Research Instrumentation and Facilities (CRIF) Program, Professor Eric Borguet from Temple University in collaboration with his colleagues Hai-Lung Dai, Robert Stanley and Robert Levis will develop an instrument capable of acting as a high energy, ultrabroadband source of ultrashort infrared (IR) pulses at wavelengths beyond 2500 nm by pumping nonlinear optical materials such as AgGaS2 and AgGaSe2. This new system will produce attosecond pulses that will allow study of electron motions in atoms and molecules in real time. This mid-infrared pulsed laser source will open a window for exploration of materials, biomolecules and chemical reactions. The system will build upon existing techniques including non-collinear optical parameter amplification (NOPA). This new source will allow researchers to do new types of nonlinear experiments such as mutidimensional IR spectroscopy and interface sensitive vibrational sum frequency spectroscopy. Intense mid-IR photons will extend the cut-off energy in high-harmonic generation (HHG) processes deeper into the X-ray region. The proposal is aimed at enhancing research and education at all levels, especially in areas such as (a) nonlinear optical spectroscopy of interfaces; (b) multidimensional infrared spectroscopy; (c) sum frequency generation vibrational spectroscopy of colloid interfaces; (d) ultrabroadband infrared spectroscopy of photobiological processes; (e) filamentation with IR pulses; (f) coherent control via vibrational excitation; and (g) long-wavelength ultrashort pulse sources as a driver of high-harmonic generation.
The laser system to be developed will generate electromagnetic radiation, light, in the infrared region of extremely short duration, attoseconds. This is one quintillionth of a second. To put this into perspective, an attosecond is to a second, what a second is to about 32 billion years. This type of light can directly excite the vibrational motion of molecules and the subsequent distribution of this energy into a material. This technique advances ultrafast laser technology. As the field grows, the significance of molecular phenomena on time scales of attoseconds and shorter is being realized. Arguably, some of the most fundamental processes in chemistry (e.g., bond breaking and formation, electron transfer, and others) occur on these ultrafast time scales. This development effort will create a new instrument with high versatility that will be used in the growing field of ultrafast spectroscopy. The instrument is part of a program to develop a strong ultrafast spectroscopic capability to stimulate a number of research programs as well as to provide a base for collaborations with colleagues. These unique attributes indicate that the new instrument will have broad applicability across many fields. During development, construction, testing and commissioning of the instrument many students will participate. This will provide a rich training experience in the growing field of ultrafast methodology while allowing study of unstable reaction products or excited states of molecules, and at the same time determining their structure while combining spectroscopy (giving structural information) and dynamics (revealing details of the reactive events).
