Page 1 of 1

SuperInsulators

Posted: Thu Apr 10, 2008 12:07 pm
by PolyGirl
An interesting article from Physorg about SuperInsulators (the opposite of SuperConductors). The article title is:

Newly discovered 'superinsulators' promise to transform materials research, electronics design.

The link is SuperInsulators.

Regards
Polygirl

Posted: Thu Apr 10, 2008 4:47 pm
by drmike
That's really cool! Thanks for posting!

Posted: Wed Apr 23, 2008 3:38 am
by cuddihy
Ok, this is a question that I'm sure people who understand physics beyond the undergrad level (not me, except with astrodynamics) wouldn't need to ask, but if superconductance and superinsulation are physically possible, what about super-dialectrance?

Or is that just asking too much of your average Cooper pair?

Posted: Wed Apr 23, 2008 4:13 am
by MSimon
A lot will depend on the field strength they can support.

Super conductors are rated by the amps / sq cm they can support.

Super insulators would be rated by the leakage current/(volt *cm).

Note that both effects are magnetic field dependent. High fields destroy both effects.

=======

Wrong equation for leakage.

(leakage current * cm)/volt

i.e. more cm = less leakage.

Posted: Wed Apr 23, 2008 1:09 pm
by drmike
Plasmas are already super-dielectrics. Look at the gas gate on a RADAR. It blocks high power from getting into the detector when the main pulse goes out, and lets the signals from the return pulse go thru easily when the main pulse is off. Ionization does the matching rather than cooper pairs.

Posted: Wed Apr 23, 2008 1:58 pm
by MSimon
drmike wrote:Plasmas are already super-dielectrics. Look at the gas gate on a RADAR. It blocks high power from getting into the detector when the main pulse goes out, and lets the signals from the return pulse go thru easily when the main pulse is off. Ionization does the matching rather than cooper pairs.
Doesn't it have to do with the plasma shorting out the leakage when the plasma forms and letting the signal through when the plasma decays?

As I recall it also involved a 1/4 wave choke section. But it has been 45 years since I studied it and I'm a little (a lot) hazy on the details.

Details:

http://www.radartutorial.eu/06.antennas/an19.en.html

Posted: Wed Apr 23, 2008 2:01 pm
by drmike
Exactly! I'd call that a "super dielectric" - transparent at low power, reflective at high power. It's only been 15years since I got to play with it....