Ising t-J model close to half filling: a Monte Carlo study

Area of Science:

• Condensed Matter Physics
• Quantum Many-Body Theory

Background:

• The t-J model is a fundamental model in condensed matter physics for describing strongly correlated electrons.
• Understanding the interplay between magnetic order and charge carriers is crucial for explaining high-temperature superconductivity.

Purpose of the Study:

• To derive and analyze a full Ising version of the t-J model.
• To investigate the destruction of antiferromagnetic order by doping and the role of hole mobility.
• To compare the properties of the Ising t-J model with the anisotropic t-J(z) and isotropic t-J models.

Main Methods:

• Derivation of the Ising t-J model from a doped-carrier representation.
• Unbiased Monte Carlo calculations on large clusters (up to 10^3 sites).
• Analysis of the effects of doping, exchange interaction, and next-nearest-neighbor hoppings on magnetic order.

Main Results:

• The Ising t-J model exhibits Z(2) symmetry and allows for large-scale unbiased simulations.
• Doping effectively destroys antiferromagnetic order, with short-range order persisting over wide temperature and doping ranges.
• The local no-double-occupancy constraint is identified as the dominant factor in destroying magnetic order at finite doping.

Conclusions:

• The Ising t-J model provides a computationally advantageous framework for studying strongly correlated electron systems.
• Hole mobility and magnetic order are intricately linked, with doping playing a critical role in their interplay.
• The findings offer insights into the complex magnetic and electronic properties relevant to materials like cuprates.