Abstract
An antenna model is proposed for long () lasers with subwavelength cross sections (wire lasers). It is shown that the far-field pattern of the wire lasers is determined by the ratio of the wavelength to the length. The radiation of the wire laser is predicted to be concentrated in a narrow beam for laser modes where the longitudinal phase velocity is in synchronism with the velocity of light in air. Experimental results obtained using a terahertz quantum cascade wire laser are in agreement with the model.
- Received 7 December 2005
DOI:https://doi.org/10.1103/PhysRevLett.96.173904
©2006 American Physical Society