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Adam Fleisher (Fed)

Research Chemist

Adam J. Fleisher is a Research Chemist at the National Institute of Standards & Technology (NIST) in Gaithersburg, MD, USA. His research is in precision molecular spectroscopy, currently applied to measurements of the isotopic composition of greenhouse gases like carbon dioxide and nitrous oxide. With colleagues, he also reports accurate measurements of absorption cross-sections for the benchmarking of advanced quantum chemistry calculations. In the laboratory, this work requires the development of advanced optical sensing techniques using optical frequency combs, quantum-cascade lasers, stabilized near-infrared lasers, and high-finesse optical resonators.

Prior to joining NIST in Gaithersburg, AJ Fleisher was a National Research Council (NRC) postdoc at JILA (University of Colorado Boulder and NIST) under the supervision of Jun Ye. He earned his Ph.D. from the University of Pittsburgh in 2011 and completed his undergraduate studies at Elizabethtown College in 2007.

AJ is an Optica (formerly OSA) Ambassador, recognized as an emerging leader in the optics and photonics community in 2019. He routinely serves on the organizing committees for several optical sensing and spectroscopy meetings and was the lead guest editor on two Joint Feature Issues of Optics Express and Applied Optics. In 2019, he participated on the Consultative Committee for Amount of Substance:  Metrology in Chemistry and Biology (CCQM) Working Group on Isotope Ratios (IRWG) at the International Bureau of Weights and Measures (BIPM) in Sèvres, France.

Click here to see Dr. Fleisher’s Google Scholar page

Research Interests

  • Frequency combs
  • Cavity-enhanced spectroscopy
  • Radiocarbon Dioxide
  • Greenhouse Gases and their Isotope Ratios
  • Time-resolved spectroscopy
  • Chemical Kinetics and Dynamics

Research Opportunities

Publication Highlights

  • “Crystalline supermirrors to advance sensing and detection,” Electro Optics magazine, 2021. {Link}

  • Editors’ Pick:  Optics Express 29, 26831–26840 (2021). {Link}

  • “Crystalline supermirrors cut optical losses,” Physics World (IOP), 2021. {Link}

  •  “Fundamental constants are the future of measurement. Can they replace artifacts for measuring isotopes?” NIST Taking Measure blog, 2021. {Link}

  • Editors’ Pick:  Optics Letters 44, 4415–4418 (2019). {Link}

  • “Corrections promise more accurate CO2 measurements from space,” Chemistry World (RSC), 2019. {Link}

  • “Synopsis:  Correcting hardware bias in molecular spectrometer,” Physics (APS), 2019. {Link}

  • Editors’ Suggestion:  Physical Review Letters 123, 043001 (2019). {Link}

  • “A benchtop test for biofuel authenticity,” Chemical & Engineering News (ACS), 2017. {Link}

  • “A new method for identifying carbon compounds derived from fossil fuels,” NIST News, 2017. {Link}

  • Cover of ChemPhysChem “Laser Chemistry and Spectroscopy” special issue, 2011. {Link}

  • JCP Editors’ Choice, Journal of Chemical Physics, 2009. {Link}

Selected Publications


Patents (2018-Present)

Created September 10, 2019, Updated December 8, 2022