Type 1 and 2 superconductors (1 Viewer)

[Freeba]

hi this may seem a stupid question but can someone please give me a proper explaination about the difference between type 1 and type 2 superconductors

so far i've got type 1 are [FONT=&quot]pure metals where superconductivity occurs at temps from close to absolute zero and up to 23K. and type 2 are those that have been manufactured using alloys of metals and metal oxides and demonstrate superconductivity at higher temperatures around 120 K


is that it?
[/FONT]

 

[Stella09]

i think that's about it.... that's a more detailed explanation than we got in class lol.... i think thats it though from what i can see, try Bob Emery's site though... it's good

 

[Freeba]

hey thanks for that...useful site

 

[Fortify]

Yeh, I think that's about it.

 

[Stella09]

Type 2 Superconductors

Type 1 Superconductors

 

[darkchild69]

Basically, Type 1 can be explained by the BCS theory -- In the real BCS theory the distance between the "Cooper Pair" electrons is 100-1000 atomic spacings. At these distances there is minimal electrostatic repulsion between the two electrons.

Type 2 cant be explained by BCS theory -- Cooper Pairs in this type of superconductor can be one or two atomic spacings apart, at such small distances, the electrostatic force between the two electrons is far greater than the attraction between the second electron and the slightly positive deformed region.. Some think it is to do with the antiferromagnetic properties of the Copper Oxide layers in the High Tc superconductors. Either way, BCS' "Cooper Pairs" cannot explain how these type of superconductors work

 

[rama_v]

There is a more technical explanation as to what constitutes a type I and type II superconductor. They are immediately characterisable by their magnetisation in response to applied fields. For a type I superconductor, magnetisation is linear in response to applied fields, and then is abruptly destroyed at a particular critical field H_c. But for type II superconductors, there exists a "vortex" or "mixed" state, characterised by some penetration of flux lines. The reason is free energy reduction as a result of forming a normal boundary between normal/mixed regions, which is greater than the energy reduction arising from opposing the external field.

Mind you, this is (rather sadly) beyond the scope of the HSC.

 

[Uncle]

There is a more technical explanation as to what constitutes a type I and type II superconductor. They are immediately characterisable by their magnetisation in response to applied fields. For a type I superconductor, magnetisation is linear in response to applied fields, and then is abruptly destroyed at a particular critical field H_c. But for type II superconductors, there exists a "vortex" or "mixed" state, characterised by some penetration of flux lines. The reason is free energy reduction as a result of forming a normal boundary between normal/mixed regions, which is greater than the energy reduction arising from opposing the external field.

Mind you, this is (rather sadly) beyond the scope of the HSC.

like many good things in physics.

The generalised form of Faraday's Law is:

[maths]\oint \vec{E} \cdot d\vec{s} = -\frac{d}{dt}\int \vec{B} \cdot d\vec{A}[/maths]

Then for Faraday's Law applied to coils with multiple turns:

[maths]\varepsilon = -N\frac{\mathrm{d\Phi _{B}} }{\mathrm{d} t}[/maths]

Then the version that is barely in the borders of the HSC physics syllabus:

[maths]\varepsilon = -N\frac{\Delta \Phi _{B}}{\Delta t}[/maths]

Then the HSC version simply an opposing induced EMF is created through the change in magnetic flux through a surface through time

 

[rama_v]

like many good things in physics.

The generalised form of Faraday's Law is:

[maths]\oint \vec{E} \cdot d\vec{s} = -\frac{d}{dt}\int \vec{B} \cdot d\vec{A}[/maths]

Then for Faraday's Law applied to coils with multiple turns:

[maths]\varepsilon = -N\frac{\mathrm{d\Phi _{B}} }{\mathrm{d} t}[/maths]

Then the version that is barely in the borders of the HSC physics syllabus:

[maths]\varepsilon = -N\frac{\Delta \Phi _{B}}{\Delta t}[/maths]

Then the HSC version simply an opposing induced EMF is created through the change in magnetic flux through a surface through time

Absolutely. In other words, HSC physics is just words without real physics.

If they had taught that at school, there would be little reason to teach it again in first year physics. But unfortunately, they decide to forgo real physics and substitute it with essays and history lessons, so when students get to uni, they quickly realise that physics is much different to what they have been taught.

 

[darkchild69]

Absolutely. In other words, HSC physics is just words without real physics.

If they had taught that at school, there would be little reason to teach it again in first year physics. But unfortunately, they decide to forgo real physics and substitute it with essays and history lessons, so when students get to uni, they quickly realise that physics is much different to what they have been taught.

Couldnt agree more.

I always tell my students this. Some of the concepts in the HSC course are interesting, but it order to truly appreciate them, you need to understand the mathematical language of why it is so. I find it very hard to explain certain concepts without delving a bit into the mathematics of it, which is far outside the syllabus, but i think it helps the understanding