Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Terahertz laser power measurement comparison



John H. Lehman, Malcolm G. White, Andreas Steiger, Ralf Mueller, Alberto R. Oliva, Yuqiang Deng, Qing Sun


Abstract: A comparison of terahertz (THz) laser power measurements was undertaken among three national metrology institutes. At two THz frequencies, 2.52 THz (119 µm) and 0.762 THz (394 µm), a power level of approximately 3 mW was compared at one place at one time by means of national standard THz detectors, which had been calibrated by each participant at their own metrology institute beforehand. The measurements took advantage of the power stability and Gaussian beam profile of the THz radiation source, consisting of a molecular gas laser pumped with a line-tunable CO2 laser at the THz detector calibration facility of PTB. A reference value was determined as weighted average of the measurement results with a maximum weight obtained from the arithmetic mean of the uncertainties stated by the participants. All measurement results agreed with the reference value and to each other within the stated expanded uncertainties.
Optics Express


Terahertz, far infrared, calibration, international comparison, thermopile, pyroelectric


Lehman, J. , White, M. , Steiger, A. , Mueller, R. , Oliva, A. , Deng, Y. and Sun, Q. (2016), Terahertz laser power measurement comparison, Optics Express, [online], (Accessed July 17, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created September 5, 2016, Updated November 10, 2018