This Partnerships for Innovation (PFI) project--a Type III (A:C) partnership between Montana State University, an NSF PFI graduate (0125429) and University of Montana, an institution new to the PFI Program (defined as one that has never been a PFI grantee)--seeks to respond to the problem of the use of methamphetamine (meth), a highly addictive illicit drug, and to meth-related crime, which has reached epidemic levels in the U.S. and particularly in the state of Montana; by developing laser-based remote sensing technologies to detect clandestine meth labs and also the hazards inside. Advances in the areas of laser operation, in detection, and knowledge of the detectable chemicals are all being addressed in the Remote Methamphetamine Detection Initiative (REMEDI) partnership, and each advance in these areas will contribute to improving the sensitivity and reducing false positives, which are essential for adoption of the device by law enforcement.
The proposed activity is focused on the development of a technology that can assist law enforcement in uncovering meth labs and also alert first responders as to which hazardous chemicals are present. The societal impact of this activity is of major importance, particularly in Native American tribal communities. The technology can also be directly extended to remotely detecting other airborne chemicals. Some of these chemicals include other drug manufacturing signature chemicals, chemical weapons, global warming chemicals, chemicals important to home security and dangerous or other toxic industrial effluents.
Partners at the inception of the project are Academic Institutions: Montana State University (lead institution), and University of Montana; Research Institution: National Jewish Medical Center; Private Sector Organizations: Battelle (not-for-profit)(Richland, WA), AdvR, Inc.; Bridger Photonics, Inc., and Scientific Materials Corporation/FLIR Systems; State and Local Organizations: Missouri River Drug Task Force, Montana Department of Justice, Division of Criminal Investigation; and Montana Governor?s Office; and Other: Montana Meth Project, Montana-Wyoming Tribal Leaders Council, and MSU TechLink.
Jeremy Schoessler 14.00 Normal 0 false false false EN-US X-NONE X-NONE This NSF PFI grant explored the development of compact tunable laser systems for remote chemical sensing in the mid-infrared (3-4 microns) wavelength range. In this wavelength range, many chemicals have well defined and unique spectral absorption signatures, including chemicals that are the by-products of the production of methamphetamines (meth). The ability to identify these meth by-products can help in law enforcement in the identification of meth labs and alert first responders to a range of dangerous chemicals (like those in meth labs, as well as other dangerous chemicals) before they enter the contaminated area. The research outcomes of this project include 1) 1) The development of optical and thermal models and simulators for aiding in the design of the compact pump lasers used in generating mid-infrared light. The non-linear process chosen for generating tunable mid-infrared light was optical parametric amplification (OPA). OPA requires a high peak power pulsed laser (operating at 1064 nm) that is single frequency and operates stably at a high repetition rate. Initially, the heat generated in the laser operation caused mis-alignment the laser and reduced its repetition rate. High repetition rates are needed to rapidly acquire sufficient data to perform quick identification of chemicals. Optical and thermal models of the lasers were developed that showed where the heat was generated and dissipated throughout the laser system, the heat- created stresses in the pump laser assembly, and the resultant optical mis-alignments. These models allowed for thermal designs with better dissipation of the heat generated in the laser operation, hardware designs that reduced the stresses that caused misalignment, and optical designs that were less susceptible to mis-alignment by thermal stresses. These improvements allowed for successful operation of the laser systems at higher repetition rates. 2) 2) The development of efficient methods to seed our OPA process to aid in accurate tuning of the mid-infrared light. The OPA process requires, in addition to the steady pump laser, a seed laser operating at 1.5 microns (telecom wavelengths), which when tuned, tunes the mid-infrared on and off the absorption features of the chemicals of to be detected. Methods that resulted in broad tuning and high spectral purity were developed. 3) 3) The development, along with our partners, of a database of the chemical by-products of different methods of producing methamphetamine and an assessment of which chemicals were identifiable via remote sensing in the mid-infrared and which wavelengths in the mid-infrared were best suited for identifying these chemicals. Also developed were chambers for the production and detection of chemical by-products of different meth cook methods. 4) 4) The demonstration of remote sensing of chemicals. A compact seeded pulsed OPA laser and detection system was designed, assembled, and used to remotely scan the mid-infrared chemical absorption profiles. 5) 5) Initial development of continuous wave (non-pulse) mid-infrared laser light generation as an alternative means of remote chemical sensing. An alternative to remote chemical sensing based on pulsed OPA is one based on continuous mid-infrared light. Continuous mid-infrared light can be produced by the non-linear optical process of differential frequency generation (DFG). Commercial continuous wave pump (at 1064 nm) and signal laser (at 1550nm) were shown to produce sufficiently high powers of mid-infrared light via DFG with periodically poled stoichiometric lithium tantalite (PPSLT) as the nonlinear optical medium. PPSLT’s high photo-refractive damage threshold and effective nonlinear coefficient allows it to handle high pump and signal intensities, and thus reach sufficient levels for efficient generation of cw mid-infrared power. In addition to the research outcomes, the major commercial outcome of this project was the development by our partner, Bridger Photonics, of a broadband version of the pulsed mid-IR OPA laser system. This spin-off broadband mid-IR source is now being sold, with the main application being laser ablation for ionization-based profiling of biomolecules. Our partner continues to pursue production of narrowband laser systems for remote chemical sensing.
