Hybrid quantum system of a nanofiber mode coupled to two chains of optically trapped atoms

Abstract

A tapered optical nanofiber simultaneously used to trap and optically interface of cold atoms through evanescent fields constitutes a new and well controllable hybrid quantum system. The atoms are trapped in two parallel 1D optical lattices generated by suitable far blue and red detuned evanescent field modes very close to opposite sides of the nanofiber surface. Collective electronic excitations (excitons) of each of the optical lattices are resonantly coupled to the second lattice forming symmetric and antisymmetric common excitons. In contrast to the inverse cube dependence of the individual atomic dipole-dipole interaction, we analytically find an exponentially decaying coupling strength with distance between the lattices. The resulting symmetric (bright) excitons strongly interact with the resonant nanofiber photons to form fiber polaritons, which can be observed through linear optical spectra. For large enough wave vectors the polariton decay rate to free space is strongly reduced, which should render this system ideal for the realization of long range quantum communication between atomic ensembles.

Atom–light interactions in photonic crystals

“…By optimizing the power and detuning of the E 1 trap mode, we should be able to achieve stable atomic trapping and ground state cooling 41,50,51 . By applying continuous on-site cooling to Nc1 atoms, we expect to create a 1D atomic lattice with single atoms trapped in unit cells along the APCW, thus opening new opportunities for studying novel quantum transport and many-body phenomena [5][6][7][8][9][10][11][12][13][14][15][16][17][18] .…”

“…L ocalizing arrays of atoms in photonic crystal waveguides (PCW) with strong atom-photon interactions could provide new tools for quantum networks [1][2][3] and enable explorations of quantum many-body physics with engineered atom-photon interactions [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] . Bringing these scientific possibilities to fruition requires creation of an interdisciplinary 'toolkit' from atomic physics, quantum optics and nanophotonics for the control, manipulation and interaction of atoms and photons with a complexity and scalability not currently possible.…”

Collective interactions in an array of atoms coupled to a nanophotonic waveguide

“…The experiments can easily achieve hundreds of atomic sites, and larger number is expected in the future for smaller lattice constant. The set-up properties justify the introduction of the concept of polariton as a natural excitation in the strong coupling regime [16].…”

“…In our previous work [16,17] the linear optical spectra was evaluated for a linear atomic lattice strongly coupled to one dimensional propagating fiber photons, where the excitations and photons are coherently mixed to introduce polaritons as the real system eigenstates [18,19]; and the atoms are considered to be of two-level systems with spin-half statistics. For the case of a single excitation at most to appear in the system no meaning of statistics and excitations can be treated either as bosons or fermions; while for two excitations and more, excitations at different sites behave as bosons and on-site excitations behave as fermions.…”

Atom-Light Interactions in Photonic Crystals

“…The fraction of single-atom radiative decay into the PCW is Γ1D/Γ (0.32 ± 0.08), where Γ1D is the rate of emission into the guided mode and Γ is the decay rate into all other channels. Γ1D/Γ is quoted without enhancement due to an external cavity and is unprecedented in all current atom-photon interfaces.Localizing arrays of atoms in photonic crystal waveguides with strong atom-photon interactions could provide new tools for quantum networks [1][2][3] and enable explorations of quantum many-body physics with engineered atom-photon interactions [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Bringing these scientific possibilities to fruition requires creation of an interdisciplinary 'toolkit' from atomic physics, quantum optics, and nanophotonics for the control, manipulation, and interaction of atoms and photons with a complexity and scalability not currently possible.…”