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Updated: Oct 26, 2025
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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Quantifying and Controlling Entanglement in the Quantum Magnet Cs_{2}CoCl_{4}
Pontus Laurell1,2, Allen Scheie3, Chiron J Mukherjee4,5
1Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
Physical Review Letters
|July 30, 2021
Summary
This study explores using inelastic neutron scattering to measure quantum entanglement in materials. Quantum Fisher information proves a robust method for detecting entanglement in quantum spin systems.
Area of Science:
- Condensed Matter Physics
- Quantum Information Science
Background:
- Experimental detection of quantum entanglement in materials is challenging, hindering the identification of exotic phases like quantum spin liquids.
- Developing model-independent protocols is crucial for characterizing entanglement in complex quantum systems.
Purpose of the Study:
- To investigate the feasibility of inelastic neutron scattering (INS) for measuring quantum entanglement.
- To implement and validate a protocol using entanglement witnesses: one-tangle, two-tangle, and quantum Fisher information (QFI).
Main Methods:
- High-resolution INS measurements on Cs_{2}CoCl_{4}, a model quantum spin system.
- Controlling entanglement via magnetic fields and comparing experimental data with density-matrix renormalization group (DMRG) calculations.
Main Results:
- Demonstrated the use of three entanglement witnesses to infer entanglement properties in a quantum material.
- Identified Quantum Fisher Information (QFI) as a particularly robust experimental probe for entanglement.
- Noted that one-tangle and two-tangle require more detailed analysis for reliable interpretation.
Conclusions:
- Established a foundation for a general entanglement detection protocol for quantum spin systems using INS.
- Highlighted the potential of INS as a versatile tool for probing quantum entanglement in condensed matter.
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