sol invictus
Philosopher
- Joined
- Oct 21, 2007
- Messages
- 8,613
Now let us return to the Josephson junction: when the charge carrier is on the higher energy side it has a potential energy qV relative to the energy on the other side, Thus, as I have clearly argued, if you can move the charge-carrier to the other side WITHOUT changing its energy and release it, it will radiate energy qV. BUT in order for the charge-carrier to move to the other side it has to move through the junction within which it encounters a voltage V; and it is then accelerated by the voltage in the junction to, IN ADDITION, gain kinetic energy qV. This is the same as throwing the hammer into the air. Thus it now has a total energy of 2qV to dissipate.
I think we should focus only on this until it is settled, because you are wrong for an extremely clear and simple reason. If we cannot agree on this, we will never agree on anything.
The energy of a charge carrier is E =K+qV(x), where K is kinetic energy, V(x) is potential energy, and q is the charge. Yes? Now, in your scenario V(x)=V for x>0 and V(x)=0 for x<0. Yes?
The initial state has K=Kmin and the carrier is at some x>0, where Kmin is the minimum allowed kinetic energy. So
Einitial=Kmin+qV
The final state (before radiating) has some K and V=0, so
Efinal=K
Since there has been no radiation,
Efinal=Einitial=Kmin+qV=K,
or
K-Kmin= qV
That how much energy can be radiated away without reducing the kinetic energy below the allowed minimum.
If you don't agree, tell me exactly which equation you don't agree with, and why.
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