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Room Temperature Semiconductor of T-Rays

Posted by CmdrTaco on from the but-what-does-it-mean-man dept.

Fallen Andy noted a Physorg story that says "Engineers and applied physicists from Harvard University have demonstrated the first room-temperature electrically-pumped semiconductor source of coherent Terahertz (THz) radiation, also known as T-rays. The breakthrough in laser technology, based upon commercially available nanotechnology, has the potential to become a standard Terahertz source to support applications ranging from security screening to chemical sensing." "What did you do at the office today, honey?" "Oh, I just demonstrated the first room-temperature electrically-pumped semiconductor source of coherent Terahertz radiation. How was your day, dear?"

2 of 110 comments (clear)

  1. Re:What can T-Rays do? by mckinnsb · · Score: 5, Informative

    From reading the article, my layman's-"I'm no physicist"'s take on T-Rays:

    1) They can penetrate through clothing/plastic/flesh, and most of the materials mentioned seem to be organic in nature. This gives them "X-ray"-like properties.
    2) They were able to make T-Rays before in laboratories, but now they can make them more cheaply, with less power, in human-friendly settings.
    3) T-Rays give off less radiation than X-rays, due to the much larger wavelength.

    Quick Conclusion: We now have the potential to create an X-ray like device that could be deployed in airports and other travel hubs that could be used to monitor the public without harming the public through this observation. More benignly, they could also be used in hospitals for "persistent monitoring" of patients with tumors or internal bleeding, because they seem to have lower power requirements and risks of side-effects.

  2. Very nice. Here's the real source by Animats · · Score: 5, Informative

    First, here's the real paper. Actually, this is the previous paper, where they got operation at 177K, but not quite room temperature. (Don't link to Physorg; they just collect press releases, add ads, and delete the citations.)

    Terahertz waves are interesting. At one time, that was an inaccessible portion of the spectrum, above radio but below infrared. Now it's understood that it's a region in which both RF and optical techniques can work. At that frequency, propagation is line of sight, although diffuse systems, as with diffuse IR, are possible. Applications are still a ways off, but there's probably something useful to do with this stuff.

    Incidentally, "radio", by international agreement, ends at 3THz. Beyond that, it's "light" for regulatory purposes. In the US, FCC regulations (for RF) end at 3THz, and DHS regulations (as for lasers) begin.