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Electric-field-controlled superconductor-ferromagnetic insulator transition.
Likuan Ma1, Bin Lei1, Naizhou Wang1
1Hefei National Laboratory for Physical Sciences at Microscale and Department of Physics, and CAS Key Laboratory of Strongly-coupled Quantum Matter Physics, University of Science and Technology of China, Hefei 230026, China.
Science Bulletin
|January 20, 2023
Summary
Researchers used a novel solid ion conductor field-effect transistor (SIC-FET) to control phase transitions between superconductivity and ferromagnetism in (Li,Fe)OHFeSe. This breakthrough offers new insights into superconductor-ferromagnetism relationships.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Solid-State Chemistry
Background:
- Superconductivity often exhibits complex relationships with magnetism, particularly in unconventional superconductors.
- Understanding mechanisms beyond electron-phonon coupling is crucial for advancing superconductivity research.
Purpose of the Study:
- To investigate the interplay between superconductivity and ferromagnetism in (Li,Fe)OHFeSe.
- To demonstrate electric-field control over phase transitions in layered materials.
- To explore the potential of solid ion conductor field-effect transistors (SIC-FETs) for tuning material properties.
Main Methods:
- Fabrication of a novel field-effect transistor utilizing a solid ion conductor as the gate dielectric (SIC-FET).
- Application of electric-field gating to induce phase transitions in (Li,Fe)OHFeSe.
- Characterization of superconducting and ferromagnetic properties as a function of gate voltage.
Main Results:
- Successful electric-field-controlled phase transition between a superconducting and a ferromagnetic insulating state in (Li,Fe)OHFeSe.
- Observation of a dome-shaped superconducting phase with a maximum Tc of 43 K.
- Ferromagnetic insulating phase exhibits electric-field-controlled quantum critical behavior.
- Ferromagnetism is attributed to the ordering of interstitial Fe ions.
Conclusions:
- The study provides a unique platform for exploring the coupling between superconductivity and ferromagnetism in iron-based superconductors.
- The SIC-FET demonstrates superior performance in regulating the physical properties of layered unconventional superconductors.
- These findings open new avenues for designing and controlling quantum materials.
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