Localization in a t-J-Type Model with Translational Symmetry.

Area of Science:

• Condensed matter physics
• Quantum magnetism

Background:

• Understanding charge carrier behavior in strongly correlated electron systems is crucial.
• The t-J model describes key physics of doped Mott insulators.

Purpose of the Study:

• Investigate the spatial localization of holes in a two-leg t-J ladder.
• Explore conditions for hole delocalization and pairing mechanisms.

Main Methods:

• Utilized the density matrix renormalization group (DMRG) method.
• Analyzed the impact of staggered chemical potential and next-nearest-neighbor hopping (t').

Main Results:

• Demonstrated explicit spatial localization of a single hole under a staggered chemical potential.
• Identified conditions for hole delocalization: disabling the phase string effect or introducing finite t'.
• Observed that two holes form a mobile bound pair, unlike localized single holes.

Conclusions:

• The staggered potential induces hole localization, influenced by the phase string effect.
• A novel pairing mechanism for two holes suggests unique properties of doped Mott insulators.