Exciton-polaritons in van der Waals heterostructures embedded in tunable microcavities Article uri icon

abstract

  • Layered materials can be assembled vertically to fabricate a new class of van der Waals heterostructures a few atomic layers thick, compatible with a wide range of substrates and optoelectronic device geometries, enabling new strategies for control of light-matter coupling. Here, we incorporate molybdenum diselenide/hexagonal boron nitride (MoSe 2 /hBN) quantum wells in a tunable optical microcavity. Part-light-part-matter polariton eigenstates are observed as a result of the strong coupling between MoSe 2 excitons and cavity photons, evidenced from a clear anticrossing between the neutral exciton and the cavity modes with a splitting of 20 meV for a single MoSe 2 monolayer, enhanced to 29 meV in MoSe 2 /hBN/MoSe 2 double-quantum wells. The splitting at resonance provides an estimate of the exciton radiative lifetime of 0.4 ps. Our results pave the way for room-temperature polaritonic devices based on multiple-quantum-well van der Waals heterostructures, where polariton condensation and electrical polariton injection through the incorporation of graphene contacts may be realized. © 2015 Macmillan Publishers Limited. All rights reserved.

publication date

  • 2015-01-01