Measuring magnetic field texture in correlated electron systems under extreme conditions

Area of Science:

• Condensed matter physics
• Quantum many-body systems
• Materials science

Background:

• Pressure is a key parameter for tuning ground states in strongly correlated electron systems.
• Existing magnetic field sensors lack sensitivity and accessibility for in-situ measurements under pressure at cryogenic temperatures.

Purpose of the Study:

• To develop a novel, sensitive, and spatially resolved magnetic field sensing technique for materials research under extreme conditions.
• To probe superconducting and magnetic properties of quantum materials under pressure.

Main Methods:

• Utilized nitrogen vacancy (NV) centers in diamond as vector magnetometers.
• Performed measurements on a single crystal of BaFe2(As0.59P0.41)2 under pressure and at cryogenic temperatures.
• Integrated NV center sensing with high-pressure and low-temperature experimental setups.

Main Results:

• Successfully extracted the superconducting transition temperature of the benchmark material.
• Mapped the local magnetic field profile in the Meissner state.
• Determined critical magnetic fields under pressure.

Conclusions:

• Nitrogen vacancy centers in diamond provide a powerful tool for in-situ magnetic field sensing in materials under pressure.
• This method enables detailed investigation of quantum many-body phenomena like superconductivity and magnetism.
• The developed technique opens new avenues for exploring exotic quantum states in condensed matter systems.