“Now we’re saying they can be small, tunable, and much more efficient. You could fit this in your backpack, or in your vehicle for wireless communication or high-resolution imaging. Because you don’t want a cyclotron in your car.”
A team of researchers have built a terahertz laser that might one day see through clothes, book covers, and even skin, using laughing gas, according to a paper in Science. The device operates in the terahertz range - a region of the electromagnetic spectrum above microwaves and below visible light. Terahertz lasers are …
Remember, the reactor only powers the time circuits....
If you use a Fisker Karma, or more likely a first gen Honda Insight, you'll never get stuck in the past again!
I find it amusing that the entire reason they used the DeLorean DMC-12 was it was so outlandishly nutty back when the movie was produced.
Except you need to think carefully about orientation. If they are horizontal cyclotrons you will need two operating in different rotations or your car might be difficult to control. Do cyclotrons work in the vertical orientation like flywheels do?
Our local buses are hybrids with flywheels (lots of hills here to recover braking energy while going down them). If you concentrate you can feel it.
This sort of apparatus has been commercially available since at least the Eisenhower administration, if the advertisements in my childhood comics are to be believed. Santa wouldn't bring me one, though, and I expect the request was part of the reason I made the "naughty" list.
"These molecules are excited by the laser’s energy and react by vibrating and rotating."
So that's why it's called Laughing Gas.
Also I thought we had the MASER before the LASER. Isn't this band more like microwave than infrared? Though it's too early in the morning for figures and I can't remember what frequency a MASER could do. Most MASER applications are now done by GaAs FETs, but some are still used.
I suppose the acronym for one of these would be TASER (Terahertz Amplification by Stimulated Emission of Radiation), but that's already taken, so they've just gone with 'terahertz laser'.
This seems to be different from existing masers because it's tunable across a relatively wide range of frequencies/wavelengths.
All the components required fit inside a shoe box and functions in room temperature.
I know this is just a Reg measure of size, but it does create the unfortunate impression that this presumably sophisticated apparatus is just a breadboard full of bits salvaged from old radio sets and housed in a shoe box.
Also can anyone suggest what dialect "functions in room temperature" is? And where is the singular subject of "functions"?
These molecules are excited by the laser’s energy and react by vibrating and rotating. The electrons can jump between energy levels, emitting photons in the terahertz range to create a laser.
1THz is about 30 cm-1 or 4meV, placing these transitions firmly into the rotational (or a very soft vibration - except N2O is a pretty rigid molecule) transition territory.
So possibly a better way to put it is to say what the electrons stay happily exactly where they were, while the madly-rotating nuclei decide to take it a little easier, and emit a soft sigh, which becomes the terahertz radiation. From the tabulated microwave transition lines, they must have rotated rather a lot - the 0.5THz lines would correspond to rotational quantum numbers of 20+. That's plenty fast.
On the other hand, that's only true if I am tumbling about with the molecule itself, where the wee lasses electrons are mostly folowing their big and positive brothers the nuclei. If I happen to lie down on the coach next to the laser to recover from all that spinning, both the electrons and the nuclei are whirling in the mad dance, and jump most synchronously together, all emiting the little screams of joy, the teraherz photons.
As I said, I hate quantum mechanics, together with their little quantum spanners and their smug little quantum grins, neither here nor there.
Yes I'll get my coat now - one with the long sleeves at the back.
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