|Abstract:||In the search for life elsewhere in our solar system, the development of tools to measure key biomarkers is a critical area of research. One biomarker found in nature on Earth is homochirality, the predominant utilization of one handedness (enantiomer) of a biological chiral molecule over another. For example, the biological prevalence of left-handed amino acids and right-handed sugars. Developing compact, low-power instruments to detect important chiral biomolecules and measure their enantiomeric excess with high sensitivity is a challenge. We are developing and testing the three-wave mixing technique for rotational spectroscopy which was demonstrated in 2013 [1, 2] to meet these challenges. The instrument can perform sensitive detection when operated as a traditional rotational spectrometer and subsequently perform chiral measurements (absolute configuration and the enantiomeric excess) by three-wave mixing without the need for derivatizing agents or prior separation of mixtures. We use W-band (70-90 GHz) and centimeter-wave (2-8 GHz) excitation sources to excite a small amount (3-5 mTorr) of gas phase chiral molecules and generate a chiral free-induction decay in the W-band. Propylene oxide is used as the test-case molecule and chiral emission is detected for its R-and S-forms with 180 degrees phase shift allowing us to differentiate the two enantiomers. The use of millimeter-wave technology in the instrument design provides a path to future reductions in size, weight, and power of the ChiralSpec instrument that make it compatible with the stringent requirements of space missions.
 D. Patterson, M. Schnell, and J.M. Doyle, “Enantiomer-specific detection of chiral molecules via microwave spectroscopy”, Nature 497, 475-478 (2013).  D. Patterson and J.M. Doyle, “Sensitive Chiral Analysis via Microwave Three-Wave Mixing”, Phys. Rev. Lett. 111, 023008 (2013).