Organic photonic bandgap microcavities doped with semiconductor nanocrystals for room-temperature on-demand single-photon sources

Abstract

We report the first experimental observation of fluorescence from single semiconductor nanocrystals (colloidal quantum dots) in microcavities. In these room-temperature experiments we observed photon antibunching from single CdSe nanocrystals doped into a chiral one-dimensional photonic bandgap liquid-crystal microcavity. The chirality resulted in high-purity, circular polarization of definite handedness of the emitted single photons. We also report the fabrication of chiral microcavities for telecom wavelengths doped with PbSe nanocrystals as well as a solution-processed-polymer microcavity with a defect layer doped with CdSe nanocrystals between two distributed Bragg reflectors. These systems with their low host fluorescence background are attractive for on-demand single-photon sources for quantum information and communication.

Single-photon experiments with liquid crystals for quantum science and quantum engineering applications

“…In the Section 2 of this paper, experimental results of room temperature, robust SPSs with definite polarization using single-emitter fluorescence in either cholesteric (Section 2.1) or nematic (Section 2.2) liquid crystal hosts are discussed [27][28][29][30][31][32][33][35][36][37][38]. A desirable polarization state (either circular with definite handedness or linear with definite direction) of a fluorescence of the emitter in a liquid crystal host can be produced either by providing a chiral microcavity environment of a planar-aligned cholesteric liquid crystal layer (Section 2.1) or by aligning emitters' dipole moments in a definite direction in a planar-aligned nematic liquid crystal (Section 2.2).…”

“…The first part (Section 2) of this paper is an overview of the main results of our more than 10-A c c e p t e d M a n u s c r i p t 4 years research on using planar-aligned monomeric or oligomeric cholesteric and nematic liquid crystals for efficiently producing single photons with definite circular and linear polarizations [27][28][29][30][31][32][33][35][36][37][38].…”

“…In addition to high-power applications of liquid crystals in laser optics [1][2][3][4][5], optical power limiters [6][7], cholesteric lasers [8][9][10][11][12][13][14][15][16], some recent new photonics applications of liquid crystals are phase plates with singularities (including q-plates with inhomogeneous patterned distribution of the local optical axis in the transverse plane) [17][18][19][20][21][22][23] and nanophotonics [24][25][26]. The purpose of this paper is to familiarize the reader with some applications of liquid crystals in quantum science and quantum engineering using as examples the experiments and methods developed at the Institute of Optics, University of Rochester [27][28][29][30][31][32][33][34][35][36][37][38][39][40][41]. Quantum optical applications of liquid crystals, mostly connected with angular momentum of light and its manipulation using q-plates, were also reported by Italian groups [17-20, 22-23, 42-43].…”

Recent advances on single photon sources based on single colloidal nanocrystals

“…Recently, the experimental observa− tion of fluorescence from single colloidal nanocrystals in microcavities by both doping of a chiral liquid−crystal microcavity and also by a microcavity fabricated by spin coating of several polymeric layers and dispersing a nano− molar concentration of NC in the waveguiding layer was reported [81]. A further step toward the practical real− ization of single NC based SPS was reported in Ref.…”

Dye-doped cholesteric lasers: Distributed feedback and photonic bandgap lasing models

“…The circular polarized single-photon sources to secure the quantum communication were proposed, by using CLC as a single-photon source of spontaneous emission with definite polarizations of single photons [30][31][32].…”