Deconstructing Magnetization Noise: Degeneracies, Phases, and Mobile Fractionalized Excitations in Tetris Artificial Spin Ice
arXiv:2311.07801 · doi:10.1073/pnas.2310777120
Abstract
Direct detection of spontaneous spin fluctuations, or "magnetization noise", is emerging as a powerful means of revealing and studying magnetic excitations in both natural and artificial frustrated magnets. Depending on the lattice and nature of the frustration, these excitations can often be described as fractionalized quasiparticles possessing an effective magnetic charge. Here, by combining ultrasensitive optical detection of thermodynamic magnetization noise with Monte Carlo simulations, we reveal emergent regimes of magnetic excitations in artificial "tetris ice". A marked increase of the intrinsic noise at certain applied magnetic fields heralds the spontaneous proliferation of fractionalized excitations, which can diffuse independently, without cost in energy, along specific quasi-1D spin chains in the tetris ice lattice.
published in PNAS (2023)
References in corpus (6)
- Dirac Strings and Magnetic Monopoles in Spin Ice Dy2Ti2O7
- Extensive degeneracy, Coulomb phase and magnetic monopoles in an artificial realization of the square ice model
- Magnetic monopole and string excitations in a two-dimensional spin ice
- Entropy-driven order in an array of nanomagnets
- Magnetic-Field-Dependent Thermodynamic Properties of Square and Quadrupolar Artificial Spin Ice
- Deconstructing Magnetization Noise: Degeneracies, Phases, and Mobile Fractionalized Excitations in Tetris Artificial Spin Ice