Antiferromagnetic fluctuations in the quantum phase transitionof the one-dimensional electron system

Quantum antiferromagnetic (AF) fluctuations that promote the charge-density-wave (CDW)-AF state phase transition in the one-dimensional (1D) extended Hubbard model are clarified for the strong correlation regime. It is clearly shown that the CDW wave function contains quantum fluctuations due to the AF domains near the phase boundary. Though the size of these AF domains stays finite, its density to the system size becomes asymptotically zero in the infinite-size limit. This indicates the quantum decoherence, or the first order phase transition between the CDW and AF state. On the other hand, the survived AF domains would naturally evolve into the quantum nucleation that triggers the CDW-AF state phase transition.