2017/06/05 by Lei Feng, Logan W. Clark, Anita Gaj +1
Physics and Astronomy · #Coherence (philosophical gambling strategy) #Cold Atom Physics and Bose-Einstein Condensates #Cosmology and Gravitation Theories #Inflation (cosmology) #Momentum (technical analysis) #Phase transition #Quantum #Quantum Electrodynamics and Casimir Effect #Quantum critical point #Quantum dynamics #Quantum fluctuation #Quantum phase transition #Quantum phases #cond-mat.quant-gas
paper · pdf · doi:10.1038/s41567-017-0011-x
8 pages, 5 figures
arxiv created 2017/06/05 · openalex created_date 2017/06/15 · openalex publication_date 2017/12/14 · arxiv updated 2017/12/19 · openalex updated_date 2026/08/05
Quantum phase transitions, transitions between many-body ground states, are of extensive interest in research ranging from condensed matter physics to cosmology. Key features of the phase transitions include a stage with rapidly growing new order, called inflation in cosmology, followed by the formation of topological defects. How inflation is initiated and evolves into topological defects remains a hot debate topic. Ultracold atomic gas offers a pristine and tunable platform to investigate quantum critical dynamics. We report the observation of coherent inflationary dynamics across a quantum critical point in driven Bose-Einstein condensates. The inflation manifests in the exponential growth of density waves and populations in well-resolved momentum states. After the inflation stage, extended coherent dynamics is evident in both real and momentum space. We present an intuitive description of the quantum critical dynamics in our system and demonstrate the essential role of phase fluctuations in the formation of topological defects.