Suppression of Ground-State Magnetization in Finite-Size Systems due to Off-Diagonal Interaction Fluctuations
Suppression of Ground-State Magnetization in Finite-Size Systems due to Off-Diagonal Interaction Fluctuations
We study a generic model of interacting fermions in a finite-size disordered system. We show that the off-diagonal interaction matrix elements induce density of state fluctuations which generically favor a minimum spin ground state at large interaction amplitude, U. This effect competes with the exchange effect which favors large magnetization …