Kondo Lattice vs. Single Impurity Kondo System

[Rasine]

In order for a dilute magnetic alloy to show the kondo effect (resistance minimum at low T), the magnetic impurites must be far apart and non-interacting.

In the Kondo lattice, the magnetic impurities are much closer togeather (one impurity per unit cell), so why does this system show the Kondo effect?

I was reading a paper and they said that this is because the exchange parameter J of the RKKY interaction between the impurites is much weaker than the Kondo temperature (Tk). I don't understand how they are comparing J to a temperature...Maybe they mean at Tk, J is much weaker in kondo lattice systems than in single impurity konodo systems.

 

[nya]

J is an energy as well as k_B*T_K.

 

[vkroom]

Your doubt is valid. The 'J' infact destroys the Kondo screening. In the dilute impurity limit one can devise the Kondo argument using lattice version of the Anderson Model. As 'J' is tuned up the Kondo screening becomes poorer and is speculated to either suppress it completely or at least weaken it significantly.

You'll find this more informative: http://arxiv.org/abs/cond-mat/0612006