Emergent Weyl excitations in systems of polar particles

Abstract

Weyl fermions are massless chiral particles first predicted in 1929 and once thought to describe neutrinos. Although never observed as elementary particles, quasiparticles with Weyl dispersion have recently been experimentally discovered in solid-state systems causing a furore in the research community. Systems with Weyl excitations can display a plethora of fascinating phenomena and offer great potential for improved quantum technologies. Here we show that Weyl excitations generically exist in three-dimensional systems of dipolar particles with weakly broken time-reversal symmetry (for example, by a magnetic field). They emerge as a result of dipolar-interaction-induced transfer of angular momentum between the $J=0$ and $J=1$ internal particle levels. We also discuss momentum-resolved Ramsey spectroscopy methods for observing Weyl quasiparticles in cold alkaline-earth-atom systems. Our results provide a pathway for a feasible experimental realisation of Weyl quasiparticles and related phenomena in clean and controllable atomic systems.

7 pages, 4 figures

References in corpus (15)

• Electric Field Effect in Atomically Thin Carbon Films
• Discovery of a Weyl Fermion Semimetal and Topological Fermi Arcs
• Experimental observation of Weyl points
• Weyl points in three-dimensional optical lattices: synthetic magnetic monopoles in momentum space
• Long-range interacting many-body systems with alkaline-earth-metal atoms
• Carrier screening, transport, and relaxation in 3D Dirac semimetals
• Unconventional localisation transition in high dimensions
• Coulomb disorder in three-dimensional Dirac systems
• Constructing a Weyl semimetal by stacking one dimensional topological phases
• Spin-orbital dynamics in a system of polar molecules
• Weyl Superfluidity in a Three-dimensional Dipolar Fermi Gas
• Conductivity of a Weyl semimetal with donor and acceptor impurities
• Three-dimensional spin-orbit coupled Fermi gases: Fulde-Ferrell pairing, Majorana fermions, Weyl fermions and gapless topological superfluidity
• Non-Fermi Liquid in Dirac Semi-metals
• The magic road to precision

Cited by in corpus (25)

• Weyl and Dirac Semimetals in Three Dimensional Solids
• Cold molecules: Progress in Quantum Engineering of Chemistry and Quantum Matter
• Topological quantum matter with cold atoms
• Topological Quantum Optics in Two-Dimensional Atomic Arrays
• Topological properties of a dense atomic lattice gas
• Photonic Band Structure of Two-dimensional Atomic Lattices
• Dipolar quantum logic for freely-rotating trapped molecular ions
• Topological photonic states in one-dimensional dimerized ultracold atomic chains
• Geometric control of collective spontaneous emission
• Topological Gapless Matters in Three-dimensional Ultracold Atomic Gases
• Dark states of multilevel fermionic atoms in doubly-filled optical lattices
• Floquet Engineering Ultracold Polar Molecules to Simulate Topological Insulators
• Tunable Topologically-protected Super- and Subradiant Boundary States in One-Dimensional Atomic Arrays
• Subradiance of multilevel fermionic atoms in arrays with filling $n\ge 2$
• Ultracold Molecule Assembly with Photonic Crystals
• Atomic spin-wave control and spin-dependent kicks with shaped subnanosecond pulses
• Squeezing multilevel atoms in dark states via cavity superradiance
• Topological phonons in arrays of ultracold dipolar particles
• Spin-orbit-coupled Bose-Einstein condensates of rotating polar molecules
• Coherence of Symmetry-Protected Rotational Qubits in Cold Polyatomic Molecules
• Adiabatic state preparation of stripe phases with strongly magnetic atoms
• Spontaneous Emission in the presence of Quantum Mirrors
• Entanglement generation in weakly-driven arrays of multilevel atoms via dipolar interactions
• Long-range interactions in Weyl dense atomic arrays protected from dissipation and disorder
• Absolute frequency measurements on the $5s5p^3$P${}_0\to 5s6d^3$D${}_1$ transition in strontium