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Fragmentation in spin ice from magnetic charge injection
E Lefrançois1,2,3, V Cathelin2, E Lhotel2
1Institut Laue Langevin, CS 20156, 38042, Grenoble, France.
Nature Communications
|August 9, 2017
Summary
Researchers created a monopole crystal in spin ice using a staggered magnetic field. This new state of matter, magnetic fragmentation, shows ordered and fluctuating magnetic moments, enabling tunable behaviors.
Area of Science:
- Condensed Matter Physics
- Magnetism
- Materials Science
Background:
- Condensed matter systems exhibit complex phenomena, including novel states of matter like Kitaev spin liquids, skyrmion phases, and spin ices.
- Spin ices are known for exotic excitations, such as magnetic monopoles (magnetic charges).
- Understanding and controlling these exotic excitations is crucial for advancing fundamental physics and material applications.
Purpose of the Study:
- To propose and demonstrate a novel mechanism for injecting magnetic monopoles into spin ice systems at equilibrium.
- To investigate the stabilization of a monopole crystal and its associated phenomenon of magnetic fragmentation.
- To explore the potential for tunable field-induced and dynamical behaviors in this newly discovered magnetic state.
Main Methods:
- Theoretical modeling to propose a mechanism for monopole injection using a staggered magnetic field.
- Experimental demonstration in the Ho2Ir2O7 pyrochlore iridate material.
- Characterization of the resulting monopole crystal and its magnetic fragmentation.
Main Results:
- Successfully stabilized a monopole crystal in Ho2Ir2O7 using a staggered magnetic field.
- Observed magnetic fragmentation, where the magnetic moment splits into ordered and fluctuating components.
- Confirmed the theoretical predictions for monopole injection and crystal formation.
Conclusions:
- A staggered magnetic field can stabilize a monopole crystal in spin ice, leading to magnetic fragmentation.
- This fragmented state exhibits distinct excitations compared to conventional spin ices.
- The findings open avenues for controlling field-induced and dynamical magnetic behaviors in novel states of matter.
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