Guided Dipolar Exciton Polaritons

  Dror Liran(1)  ,  Itamar Rosenberg(1)  ,  Kenneth West(3)  ,  Loren Pfeiffer(3)  ,  Ronen Rapaport(1,2)  
[1] Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
[2] The Applied Physics Department, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
[3] Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544,USA

Exciton-polaritons are quantum superpositions of light and matter resulting from the strong coupling between confined optical modes  and confined electronic excitations (excitons).  They have very small effective masses ~10-5 m0 and very large propagation velocities, on the one hand, while maintaining the ability to interact with each other, as well with external electric or magnetic fields on the other hand. This conjunction of properties induces effectively strong nonlinearities to the medium leading to "interacting photons". As such, polariton quasi-particles hold promise for realizations of light-based quantum devices with new functionalities.

Here we demonstrate two types of waveguide structures which optically confine the polaritons in two dimensions and act as polaritonic channels. We show a strong optical confinement in an etched rectangular waveguide, that significantly increases the propagation distance of the polaritons and allow to direct them in curved trajectories. Also, we show low-loss optical guiding over a record-high of hundreds of microns is combined seamlessly with electrical control of the polaritons, in a strip waveguide formed by electrically conductive and optically transparent strips, which are deposited on top of a planar waveguide. Both the structures are scalable and easy to fabricate and offer new possibilities for designing complex polaritonic devices.