2014 Progress Report: Compact Multi-Pollutant Mid-Infrared Laser Spectroscopic Trace-Gas Sensor

EPA Grant Number: R835137
Title: Compact Multi-Pollutant Mid-Infrared Laser Spectroscopic Trace-Gas Sensor
Investigators: Wysocki, Gerard
Institution: Princeton University
EPA Project Officer: Chung, Serena
Project Period: February 1, 2012 through January 31, 2016
Project Period Covered by this Report: February 1, 2014 through January 31,2015
Project Amount: $250,000
RFA: Developing the Next Generation of Air Quality Measurement Technology (2011) RFA Text |  Recipients Lists
Research Category: Air Quality and Air Toxics , Air


This project will focus on development of a compact, cryogen-free trace gas sensor node targeting the spectral range containing the absorption band of benzene, which is a highly toxic atmospheric pollutant. The proposed proof-of-concept instrumentation will also provide multi-species sensing capabilities through application of novel broadband mid-infrared (IR) lasers.

Progress Summary:

The project is carried out accordingly to the originally proposed research plan with slightly revised aims according to the research performed within this project in the prior years. Four major research tasks focus on: (1) design and build a laboratory breadboard prototype, (2) laboratory tests and calibration of the breadboard prototype, (3) develop laser-based sensor node with wireless sensor network capabilities, and (4) field test and instrument inter-comparison. In the 2014 report, we have identified the main shortcoming of the EC-QCL (external cavity quantum cascade lasers) technology, namely its opto-mechanical stability restricts its use to laboratory conditions and prevents future field applications. Therefore, in addition to the main goals indicated in the original research proposal, we were developing and testing new laser technologies based on integrated semiconductor lasers that are more suitable to successfully accomplish the proposed research plan. Based on tests of five laser technologies (EC-QCL (external cavity quantum cascade laser) and DFB-QCL (distributed feedback  quantum cascade lasers) in year 1, DBR-QCL (distributed Bragg reflector quantum cascade laers) in year 2, FP-QCLs (Fabry-Perot quantum cascade lasers) and a prototype multi-DFB-QCL array in year 3), we concluded that the most promising technology for benzene detection is multi-DFB-QCL array, thus in year 4 we plan to develop a fully functional benzene sensor prototype that will be calibrated and tested in the laboratory conditions. Year 3 efforts were focused on testing of two new laser technologies for the detection of broadband absorbers (e.g., benzene) with high resolution. First, the new method of performing broadband mid-infrared spectroscopy with conventional, free-running, continuous wave FP-QCLs has been studied. We have quantified the noise in multi‐heterodyne spectrometers based on interband- and quantum-cascade lasers, and studied the modulation capabilities of QCLs that are essential to development of reliable spectroscopic systems. Last but not least, we have performed testing of an industrial prototype of the multi‐DFB‐QCL laser (from EOS Photonics Inc.) as the spectroscopic source in the benzene sensor system. We have implemented the multi‐DFB‐QCL laser as the spectroscopic engine in benzene sensor system.

Future Activities:

In the next reporting period, we plan to continue work on laboratory tests and calibration of the breadboard prototype and demonstration of atmospheric trace gas measurements with the developed prototype sensor.

Journal Articles on this Report : 3 Displayed | Download in RIS Format

Other project views: All 21 publications 5 publications in selected types All 5 journal articles
Type Citation Project Document Sources
Journal Article Hangauer A, Spinner G, Nikodem M, Wysocki G. High frequency modulation capabilities and quasi single‐sideband emission from a quantum cascade laser. Optics Express 2014;22(19):23439‐23455. R835137 (2014)
R835137 (Final)
  • Abstract from PubMed
  • Full-text: OSA-Full Text HTML
  • Abstract: OSA-Abstract
  • Other: OSA-Full Text PDF
  • Journal Article Hangauer A, Wysocki G. Gain compression and linewidth enhancement factor in mid‐IR quantum cascade lasers. IEEE Journal of Selected Topics in Quantum Electronics 2015;21(6):1200411 (11 pp.). R835137 (2014)
    R835137 (Final)
  • Full-text: ResearchGate-Full Text PDF
  • Abstract: IEEE-Abstract
  • Journal Article Wang Y, Soskind MG, Wang W, Wysocki G. High‐resolution multi‐heterodyne spectroscopy based on Fabry‐Perot quantum cascade lasers. Applied Physics Letters 2014;104(3):031114. R835137 (2013)
    R835137 (2014)
    R835137 (Final)
  • Abstract: AIP-Abstract
  • Supplemental Keywords:

    Laser spectroscopy, multi-species detection, trace-gas sensor networks;

    Progress and Final Reports:

    Original Abstract
  • 2012 Progress Report
  • 2013 Progress Report
  • Final Report