Quantum gases. Observation of isolated monopoles in a quantum field.
Topological defects play important roles throughout nature, appearing in contexts as diverse as cosmology, particle physics, superfluidity, liquid crystals, and metallurgy. Point defects can arise naturally as magnetic monopoles resulting from symmetry breaking in grand unified theories. We devised an experiment to create and detect quantum mechanical analogs of such monopoles in a spin-1 Bose-Einstein condensate. The defects, which were stable on the time scale of our experiments, were identified from spin-resolved images of the condensate density profile that exhibit a characteristic dependence on the choice of quantization axis. Our observations lay the foundation for experimental studies of the dynamics and stability of topological point defects in quantum systems.
Department of Physics and Astronomy, Amherst College, Amherst, MA 01002, USA.
M W
MW
Ray
QCD Labs, COMP Centre of Excellence, Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland.
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E
Ruokokoski
QCD Labs, COMP Centre of Excellence, Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland.
K
K
Tiurev
QCD Labs, COMP Centre of Excellence, Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland. Low Temperature Laboratory (OVLL), Aalto University, FI-00076 Aalto, Finland. mikko.mottonen@aalto.fi.
M
M
Möttönen
Department of Physics and Astronomy, Amherst College, Amherst, MA 01002, USA.
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DS
Hall