Widely tunable compact terahertz gas lasers

Paul Chevalier; Arman Amirzhan; Fan Wang; Marco Piccardo; Steven G Johnson; Federico Capasso; Henry O Everitt

doi:10.1126/science.aay8683

Widely tunable compact terahertz gas lasers

Science. 2019 Nov 15;366(6467):856-860. doi: 10.1126/science.aay8683.

Authors

Paul Chevalier¹, Arman Amirzhan¹, Fan Wang², Marco Piccardo¹, Steven G Johnson^{3

4}, Federico Capasso⁵, Henry O Everitt^{6

7}

Affiliations

¹ Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.
² Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
³ Department of Mathematics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
⁴ Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
⁵ Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA. everitt@phy.duke.edu capasso@seas.harvard.edu.
⁶ U.S. Army Combat Capabilities Development Command Aviation and Missile Center, Redstone Arsenal, AL 35898, USA. everitt@phy.duke.edu capasso@seas.harvard.edu.
⁷ Department of Physics, Duke University, Durham, NC 27708, USA.

PMID: 31727831
DOI: 10.1126/science.aay8683

Abstract

The terahertz region of the electromagnetic spectrum has been the least utilized owing to inadequacies of available sources. We introduce a compact, widely frequency-tunable, extremely bright source of terahertz radiation: a gas-phase molecular laser based on rotational population inversions optically pumped by a quantum cascade laser. By identifying the essential parameters that determine the suitability of a molecule for a terahertz laser, almost any rotational transition of almost any molecular gas can be made to lase. Nitrous oxide is used to illustrate the broad tunability over 37 lines spanning 0.251 to 0.955 terahertz, each with kilohertz linewidths. Our analysis shows that laser lines spanning more than 1 terahertz with powers greater than 1 milliwatt are possible from many molecular gases pumped by quantum cascade lasers.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.