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I am reading Tinkham's Introduction to Superconductivity (2nd ed) (Amazon link).

On pages 4-5, they state that:"

The second London equation 1.4, when combined with the Maxwell equation ${\rm curl}\ h = \frac{4\pi J}{c}$ leads to: $$\nabla^2 h = \frac{h}{\lambda^2}$$

where equation (1.4) is:

$$\ h=-c\ {\rm curl} \ (\Lambda J_s )\tag{1.4}$$ $$\Lambda = \frac{4\pi \lambda^2}{c^2}$$

If I take a curl on (1.4) and equate it with Maxwell equation I get: $${\rm curl} \ h = - c \ {\rm curl}\ {\rm curl}\ (\Lambda J_s) = -c(\nabla(\nabla \cdot) -\nabla^2)\Lambda J_s=(\dagger);$$

I don't see how do they get $\nabla^2h =h/\lambda^2$. I do get: $\nabla^2 J =J/\lambda^2$, if the first term in $(dagger)$ is zero, and $J_s=J$.

So is this a misprint in the book, or am I mistaken?

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Hints:

  1. Given the Maxwell equation: $$ \nabla\times\mathbf h=\frac{4\pi}{c}\mathbf J $$ Take the curl of both sides, what do you get? How can (1.4) be used here?
  2. Vector calculus tells you $$ \nabla\times\nabla\times\mathbf a=\nabla\left(\nabla\cdot\mathbf a\right)-\nabla^2\mathbf a $$ What assumptions must you make to get the London equation?
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  • $\begingroup$ I did just that and got what I wrote, $\nabla^2 J = J /\lambda^2$ $\endgroup$ Commented Dec 26, 2014 at 17:20
  • $\begingroup$ You're trying to prove the relationship with $\mathbf h$, so I'm not sure why you insist that $\mathbf J$ is there. $\endgroup$
    – Kyle Kanos
    Commented Dec 26, 2014 at 17:39
  • $\begingroup$ Since, if $curl h = 4\pi /c J$ and , $h=-c \ curl (\Lambda J)$, then $curl \ h = -c \ curl \ curl \ (\Lambda J) = c\Lambda \nabla^2 J$, equating I get a relation between Laplacian of J and J, I don't see how do they get the relation for laplacian of h and h. $\endgroup$ Commented Dec 26, 2014 at 17:45
  • $\begingroup$ Then you have not yet followed my directions/suggestions. $\endgroup$
    – Kyle Kanos
    Commented Dec 26, 2014 at 18:20
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    $\begingroup$ Think about it: you are trying to find a relationship for $h$, right? So why are you replacing it when you should be gathering it? $\endgroup$
    – Kyle Kanos
    Commented Dec 26, 2014 at 18:33

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