6533b824fe1ef96bd12800bc

RESEARCH PRODUCT

Free fermion antibunching in a degenerate atomic Fermi gas released from an optical lattice

D. Van OostenImmanuel BlochB. ParedesSimon FöllingTh. BestUlrich SchneiderT. Rom

subject

PhysicsCondensed Matter::Quantum GasesQuantum PhysicsOptical latticeMultidisciplinaryDegenerate energy levelsFOS: Physical sciencesQuantum phasesFermionCondensed Matter - Soft Condensed MatterFermionic condensateCondensed Matter - Other Condensed MatterQuantum mechanicsQuantum systemSoft Condensed Matter (cond-mat.soft)Fermi gasQuantum Physics (quant-ph)QuantumOther Condensed Matter (cond-mat.other)

description

Noise in a quantum system is fundamentally governed by the statistics and the many-body state of the underlying particles. Whereas for bosonic particles the correlated noise observed for e.g. photons or bosonic neutral atoms can still be explained within a classical field description with fluctuating phases, the anticorrelations in the detection of fermionic particles have no classical analogue. The observation of such fermionic antibunching is so far scarce and has been confined to electrons and neutrons. Here we report on the first direct observation of antibunching of neutral fermionic atoms. Through an analysis of the atomic shot noise in a set of standard absorption images, of a gas of fermionic 40K atoms released from an optical lattice, we find reduced correlations for distances related to the original spacing of the trapped atoms. The detection of such quantum statistical correlations has allowed us to characterise the ordering and temperature of the Fermi gas in the lattice. Moreover, our findings are an important step towards revealing fundamental fermionic many-body quantum phases in periodic potentials, which are at the focus of current research.

https://dx.doi.org/10.48550/arxiv.cond-mat/0611561