Proposal for the detection of magnetic monopoles in spin ice via nanoscale magnetometry

Journal article

We present a proposal for applying nanoscale magnetometry to the search for magnetic monopoles in the spin ice materials holmium and dysprosium titanate. Employing Monte Carlo simulations of the dipolar spin ice model, we find that when cooled to below 1.5K these materials exhibit a sufficiently low monopole density to enable the direct observation of magnetic fields from individual monopoles. At these temperatures we demonstrate that noise spectroscopy can capture the intrinsic fluctuations associated with monopole dynamics, allowing one to isolate the qualitative e↵ects associated with both the Coulomb interaction between monopoles and the topological constraints implied by Dirac strings. We describe in detail three di↵erent nanoscale magnetometry platforms (muon spin rotation, nitrogen vacancy defects, and nanoSQUID arrays) that can be used to detect monopoles in these experiments, and analyze the advantages of each.

Authors: Kirschner, F; Flicker, F; Yacoby, A; Yao, N; Blundell, S

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Physical Society
• Journal: Physical Review B
• Volume: 97
• Issue: 14
• Pages: 140402(R)
• Publication date: 2018-04-17
• Acceptance date: 2018-04-09
• DOI: 10.1103/PhysRevB.97.140402
• EISSN: 2469-9969
• ISSN: 2469-9950