15 research outputs found
Electrically tunable organic-inorganic hybrid polaritons with monolayer WS2.
Exciton-polaritons are quasiparticles consisting of a linear superposition of photonic and excitonic states, offering potential for nonlinear optical devices. The excitonic component of the polariton provides a finite Coulomb scattering cross section, such that the different types of exciton found in organic materials (Frenkel) and inorganic materials (Wannier-Mott) produce polaritons with different interparticle interaction strength. A hybrid polariton state with distinct excitons provides a potential technological route towards in situ control of nonlinear behaviour. Here we demonstrate a device in which hybrid polaritons are displayed at ambient temperatures, the excitonic component of which is part Frenkel and part Wannier-Mott, and in which the dominant exciton type can be switched with an applied voltage. The device consists of an open microcavity containing both organic dye and a monolayer of the transition metal dichalcogenide WS2. Our findings offer a perspective for electrically controlled nonlinear polariton devices at room temperature
Trionic Optical Potential for Electrons in Semiconductors
Laser-induced optical potentials for atoms have led to remarkable advances in
precision measurement, quantum information, and towards addressing fundamental
questions in condensed matter physics. Here, we describe analogous optical
potentials for electrons in quantum wells and wires that can be generated by
optically driving the transition between a single electron and a three-body
electron-exciton bound state, known as a trion. The existence of a bound trion
state adds a term to the ac Stark shift of the material proportional to the
light intensity at the position of the electron. According to our theoretical
calculations, this shift can be large relative to the thermal equilibrium
temperature of the electron, resulting in a relatively strong optical potential
that could be used to trap, guide, and manipulate individual electrons within a
semiconductor quantum well or wire. These potentials can be thought of as
artificial nano-structures on the scale of 100 nm that can be spin-dependent
and reconfigurable in real-time. Our results suggest the possibility of
integrating ultrafast optics and gate voltages in new resolved-carrier
semiconductor opto-electronic devices, with potential applications in fields
such as nano-electronics, spintronics, and quantum information processingComment: Article and Supplemental Materials; This is a preprint of the
original submission to Nature Physic