This article is within the scope of WikiProject Physics, a collaborative effort to improve the coverage of
Physics on Wikipedia. If you would like to participate, please visit the project page, where you can join
the discussion and see a list of open tasks.PhysicsWikipedia:WikiProject PhysicsTemplate:WikiProject Physicsphysics articles
This article is within the scope of WikiProject Electrical engineering, a collaborative effort to improve the coverage of
Electrical engineering on Wikipedia. If you would like to participate, please visit the project page, where you can join
the discussion and see a list of open tasks.Electrical engineeringWikipedia:WikiProject Electrical engineeringTemplate:WikiProject Electrical engineeringelectrical engineering articles
Much less than 1 (close to zero; it accounts for oxygen non-stoichiometry).
Materialscientist (
talk) 01:09, 27 January 2010 (UTC)reply
(I changed it, it's usually x, sometimes delta.) x is controlled by the crystal growth conditions. At "optimal" doping (highest Tc), x is generally thought to be around 0.08 per copper atom in the empirical formula, although in general there is no good way to directly measure x. Tc depends on x. x can go quite a bit higher (not sure how high it can be pushed).
Gruntler (
talk) 02:03, 28 January 2010 (UTC)reply
I'm dubious whether wires are made in tubes, I thought the crystals were aligned on tape as this ensured the conducting layer was in the same or close to plane.
Anyone have anymore insight or sources? —Preceding
unsigned comment added by
Joshsiret (
talk •
contribs) 21:15, 12 August 2010 (UTC)
The critical current (480A/cm2) can not be that low, even a copper conductor can withstand 600A/cm2, it has to be 93000 A/cm2 (T=4.2K).
http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=919692
Moreover, the value is temperature dependent and can not be given in general. —Preceding
unsigned comment added by
82.113.106.91 (
talk) 01:57, 4 February 2010 (UTC)reply
I have corrected the numbers per previous reference. Jc indeed varies strongly with temperature, but the temperature is specified. Further comments?
Materialscientist (
talk) 02:11, 4 February 2010 (UTC)reply
That measurement was in a B-field on silver-sheathed filaments. Here's a report
[1] of 2*10^6 A/cm^2 in single crystal. The text notes that Jc is highly dependent on the details of the growth process. Not sure what is best to include.
Gruntler (
talk) 16:23, 6 February 2010 (UTC)reply
Zero-field as I recall. Crystals are usually the standard material in other areas, but I'm not sure here too, because Jc is a practical parameter, and crystals are not used in applications. Perhaps this is unimportant: because of the strong dependence on several parameters, some value (for well specified conditions) will do.
Materialscientist (
talk) 01:03, 7 February 2010 (UTC)reply
Unit cell
This figure of Bi2212 unit cell is right? The lowest layer, BiO, differs from the highest layer. So What happen if it is translated in c axis direction?
Critical current density
a critical current density (maximal amperes per square metre of cross-sectional area) in the Bi-2223 filaments of 5×105 Amps/cm2 -- Should this be Amps/m2 rather than cm2?
Danwoodard (
talk) 17:43, 14 February 2013 (UTC)reply