Quantum Spin Liquid Phase in the Shastry-Sutherland Model Revealed by High-Precision Infinite Projected...

Area of Science:

• Condensed Matter Physics
• Quantum Magnetism
• Materials Science

Background:

• The Shastry-Sutherland model describes the behavior of layered quantum magnets, such as SrCu_{2}(BO_{3})_{2}.
• Its phase diagram, particularly at zero magnetic field, has been a subject of recent scientific debate.
• Understanding these phases is crucial for developing novel electronic materials.

Purpose of the Study:

• To resolve the controversy surrounding the phase diagram of the Shastry-Sutherland model at zero magnetic field.
• To accurately determine the ground state properties of the model using advanced computational techniques.
• To identify and characterize potential quantum spin liquid phases.

Main Methods:

• Large-scale simulations utilizing infinite projected entangled-pair states (iPEPS), a powerful two-dimensional tensor network approach.
• Direct representation of the ground state in the thermodynamic limit.
• Application of state-of-the-art optimization techniques to achieve lower energy variational states.

Main Results:

• The study obtained variational states with unprecedentedly low energies, surpassing previous computational results.
• Systematic extrapolations to the thermodynamic limit revealed key phase boundaries.
• A narrow quantum spin liquid phase was identified within the specific parameter range of 0.785(5)≤J^{'}/J≤0.82(1).

Conclusions:

• The research confirms the existence of a quantum spin liquid phase between the plaquette and antiferromagnetic phases.
• This finding provides critical insights into the complex phase diagram of the Shastry-Sutherland model.
• The study advances the understanding of quantum magnetism in layered materials.