Color-Tunable Mixed-Cation Perovskite Single Photon Emitters

Abstract

Quantum photonics technologies, like wavelength division multiplexing (WDM), for high-rate quantum key distribution require narrowband, spectrally tunable single photon emitters. Physical methods that rely on the application of large mechanical strain to epitaxial quantum dots or electric and magnetic fields to color centers in 2D metal dichalcogenides provide limited spectral tunability. Here we adopt a chemical approach to synthesize a family of colloidal mixed-cation perovskite quantum dots (Cs 1−x FA x PbBr 3 ) that show highly photostable, compositionally tunable single photon emission at room temperature, spanning more than 30 nm in the visible wavelength spectral range. We find that tailoring the stoichiometry of the organic formamidinium (FA) cation in all-inorganic cesium lead bromide (CsPbBr 3 ) perovskite quantum dots detunes the electronic band structure while preserving their excellent single photon emission characteristics. We argue that the mixed-cation perovskite quantum dots studied in this work offer a new platform for the realization of colortunable single photon emitters that could be readily integrated in a diversity of quantum photonic devices.

Accelerated polaron formation in perovskite quantum dots monitored via picosecond infrared spectroscopy

“…We can therefore conclude that the 11 nm-size nanocrystals employed here can be considered as quantum dots and are subject to quantum confinement effects which can also be seen in their single photon emission characteristics published elsewhere. 23…”

“…We can therefore conclude that the 11 nm-size nanocrystals employed here can be considered as quantum dots and are subject to quantum confinement effects which can also be seen in their single photon emission characteristics published elsewhere. 23 As we are using time-resolved vibrational spectroscopy to examine the excited perovskite samples, an infrared groundstate characterization of the samples is required. In Fig.…”

Weakly Confined Organic–Inorganic Halide Perovskite Quantum Dots as High-Purity Room-Temperature Single Photon Sources

“…Hence, there is a trade-off between achieving high single photon purity and suppressing blinking with the quantum confinement approach. Simultaneously fulfilling both qualities in strongly confined all-inorganic PQDs remains highly challenging. − ,, …”

“…Until now, the most effective approach to achieve high-purity single photon emission with inorganic CsPbX 3 (X = Cl, Br, or I) PQDs is through employing strong quantum confinement to enhance the Auger recombination (AR) of biexcitons. 3,[9][10][11][12][13][14][15]22,23 The metric defining the single photon purity of a SPS is the second-order intensity correlation function, g (2) (0) ≈ 4τ XX /τ X , where g (2) (0) = 0 reflects the ideal case. 24 Here, τ XX (τ X ) is the biexciton (exciton) lifetime.…”

Highly Photostable Zn-Treated Halide Perovskite Nanocrystals for Efficient Single Photon Generation

“…29 Additionally, they can provide tunable absorption and emission spectra across the visible range by controlling their size and composition. They also display relatively narrow emission line widths (12−50 nm) and short PL lifetimes (1−29 ns) 30,31 already at room temperature. Finally, their ease of fabrication using well-established wetchemistry techniques adds to their appeal, making them a costeffective option.…”