1,721,084 research outputs found
Polariton lasers. Hybrid light–matter lasers without inversion
No full textPolariton lasers are coherent emitters in which the fundamental constituents are not photons amplified by a gaining medium but hybrid, part exciton and part photon, quasi-particles named polaritons. In this review we discuss some of the main topics in the field of polariton lasing: we start from an introduction to the concepts of strong coupling regime and polaritons, we then discuss the mechanism of polariton lasing and the main difficulties in achieving it. Some of the main results on polariton lasing reported in the literature, from 2D samples to confined structures, are then reviewed. This latter case will allow us to discuss some of the peculiarities of polariton lasing with respect to traditional lasers. Polariton lasing mostly occurs at cryogenic temperatures, but we will see that it can also be observed at room temperature with a proper choice of materials. To conclude, we will discuss some perspectives for the field
Active stabilization of a Michelson interferometer at an arbitrary phase with subnanometer resolution
No full textWe report on the active stabilization of a Michelson interferometer at an arbitrary phase angle with a precision better than 1° at λ=632.8 nm, which corresponds to a precision in the optical path difference between the two arms of less than 1 nm. The stabilization method is ditherless, and the error signal is computed from the spatial shift of the interference pattern of a reference laser, measured in real-time with a CCD array detector. We discuss the usefulness of this method for nanopositioning, optical interferometry, and quantum optical experiments
Nonclassical light sources for silicon photonics
No full textQuantum photonics has recently attracted a lot of attention for its disruptive potential in emerging tech- nologies like quantum cryptography, quantum communication and quantum computing. Driven by the impressive development in nanofabrication technologies and nanoscale engineering, silicon photonics has rapidly become the platform of choice for on-chip integration of high performing photonic devices, now extending their functionalities towards quantum-based applications. Focusing on quantum Infor- mation Technology (qIT) as a key application area, we review recent progress in integrated silicon-based sources of nonclassical states of light. We assess the state of the art in this growing field and highlight the challenges that need to be overcome to make quantum photonics a reliable and widespread technology
Guided Bloch surface wave polaritons
No full textWe have reported on a theoretical investigation of guided polariton states arising from the strong coupling between quantum-well excitons and a Bloch surface wave confined at the interface between a uniform dielectric medium and a Bragg mirror. It is shown that the exciton–photon coupling is almost doubled as compared to a similar structure made in a conventional planar microcavity. It is also shown that, by simple engineering of the sample surface with silicon oxide deposition, one can efficiently produce one-dimensional polaritons propagating within the structure with extremely low losses. The latter result evidences the usefulness of Bloch surface waves as a key component for the realization of “polaritonic integrated circuits.
Strong Light-Matter Interaction between Guided Bloch Surface Waves and Quantum-Well Excitons
No full textWe report on a theoretical investigation of guided polariton states arising from the strong coupling between a single quantum-well exciton and a Bloch Surface Wave in a multi-layered structure. We show that the polariton Rabi splitting can be increased by almost 40% as compared to that achievable in a similar structure made in a conventional planar microcavity. Moreover, we theoretically demonstrate that by simple engineering of the sample surface with oxide deposition, one can obtain 1D polaritons propagating within the structure. The latter result shows the usefulness of our proposed device as a key component for the realization of "polaritonic integrated circuits"
Quantum degeneracy of polaritons in a GaAs based Microcavity
No full textPolariton quantum degeneracy is obtained in a GaAs Microcavity by pulsed resonant excitation of the excitonic, reservoir. Time resolved emission is monitored in this stimulated regime along the polariton branch.
Analyzing the polariton population distribution for different time delays, we conclude that polariton thermalization is not achieved and that the dynamics is governed by the scattering kinetics from the reservoir into the polariton trap
Photon lasing in GaAs microcavity: Similarities with a polariton condensate
No full textWe study experimentally the lasing regime of a GaAs based microcavity sample under strong optical pumping. The very same sample exhibits the strong coupling regime at low excitation power with a Rabi splitting as large as 15 meV. We show that some features which may be considered as experimental evidence of polariton Bose-Einstein condensation are also observed in the weak coupling regime when the cavity is behaving as a regular photon laser. In particular, the emission pattern in the lasing regime displays a sharp peak near the energy minimum followed by a Boltzmann distribution at higher energies
Erratum: “Guided Bloch surface wave polaritons” [Appl. Phys. Lett. 98, 121118 (2011)]
No full textThere is an error with the unit of measurements for energy in the text. Throughout the whole paper, the word “MeV” is used instead of “meV.
Guided Bloch Surface Wave polaritons: A route towards polariton circuits
Full text linkWe report on the strong coupling between a single quantum-well and guided Bloch Surface Waves. This results in a guided polariton that may serve as a component for the realization of "polaritonic integrated circuits"
Optical Properties of Polystyrene opals infiltrated with cyanine dyes in the form of J-aggregates
No full textWe report preliminary data on the infiltration of polystyrene opals with cyanine dye water solutions, which are known to form J-aggregates. Different approaches are used to infiltrate cyanines inside opals. The degree of infiltration is evaluated by scanning and transmission electron microscopy as well as micro reflectance spectroscopy. Data show that in spite of the low wettability of polystyrene with water solutions, some infiltration can be achieved. Even though this degree of infiltration is still not enough to observe strong modification on the photonic band structures, further strategies to improve it are in progress
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