Microsecond Blinking Events in the Fluorescence of Colloidal Quantum Dots Revealed by Correlation Analysis on Preselected Photons

Nearly all colloidal quantum dots, when measured at the single-emitter level, exhibit fluorescence “blinking”. However, despite over 20 years of research on this phenomenon, its microscopic origins are still debated. One reason is a gap in available experimental information, specifically for dynamics at short (submillisecond) time scales. Here, we use photon-correlation analysis to investigate microsecond blinking events in individual quantum dots. While the strongly distributed kinetics of blinking normally makes such events difficult to study, we show that they can be analyzed by excluding photons emitted during long bright or dark periods. Moreover, we find that submillisecond blinking events are more common than one might expect from extrapolating the power-law blinking statistics observed on longer (millisecond) time scales. This result provides important experimental data for developing a microscopic understanding of blinking. More generally, our method offers a simple strategy for analyzing microsecond switching dynamics in the fluorescence of quantum emitters.

[1]  D. Nesbitt,et al.  Modified power law behavior in quantum dot blinking: a novel role for biexcitons and auger ionization. , 2009, Nano letters.

[2]  R. Marcus,et al.  Evidence for a diffusion-controlled mechanism for fluorescence blinking of colloidal quantum dots , 2007, Proceedings of the National Academy of Sciences.

[3]  S. Leone,et al.  Mechanisms for charge trapping in single semiconductor nanocrystals probed by fluorescence blinking. , 2013, Chemical Society reviews.

[4]  D. Nesbitt,et al.  Origin and control of blinking in quantum dots. , 2016, Nature nanotechnology.

[5]  B. Dubertret,et al.  Towards non-blinking colloidal quantum dots. , 2008, Nature materials.

[6]  Paul Mulvaney,et al.  Two Mechanisms Determine Quantum Dot Blinking. , 2018, ACS nano.

[7]  B. Dubertret,et al.  Bright and grey states in CdSe-CdS nanocrystals exhibiting strongly reduced blinking. , 2009, Physical review letters.

[8]  A. Efros,et al.  Random Telegraph Signal in the Photoluminescence Intensity of a Single Quantum Dot , 1997 .

[9]  Y. Kanemitsu,et al.  Coulomb-Enhanced Radiative Recombination of Biexcitons in Single Giant-Shell CdSe/CdS Core/Shell Nanocrystals. , 2017, The journal of physical chemistry letters.

[10]  D. Gamelin,et al.  Delayed Exciton Emission and Its Relation to Blinking in CdSe Quantum Dots. , 2015, Nano letters.

[11]  Paul Mulvaney,et al.  Synthesis of Highly Luminescent and Photo-Stable, Graded Shell CdSe/CdxZn1–xS Nanoparticles by In Situ Alloying , 2013 .

[12]  Benoit Dubertret,et al.  Quasi 2D colloidal CdSe platelets with thicknesses controlled at the atomic level. , 2008, Journal of the American Chemical Society.

[13]  M. Bawendi,et al.  Challenge to the charging model of semiconductor-nanocrystal fluorescence intermittency from off-state quantum yields and multiexciton blinking. , 2010, Physical review letters.

[14]  R. Marcus,et al.  Diffusion-controlled electron transfer processes and power-law statistics of fluorescence intermittency of nanoparticles. , 2005, Physical review letters.

[15]  A. Alivisatos,et al.  Understanding the Bias Introduced in Quantum Dot Blinking Using Change Point Analysis , 2016 .

[16]  Han Htoon,et al.  Disentangling the effects of clustering and multi-exciton emission in second-order photon correlation experiments. , 2013, Optics express.

[17]  Justin R. Caram,et al.  Slow-Injection Growth of Seeded CdSe/CdS Nanorods with Unity Fluorescence Quantum Yield and Complete Shell to Core Energy Transfer. , 2016, ACS nano.

[18]  M. Bawendi,et al.  Sample-averaged biexciton quantum yield measured by solution-phase photon correlation. , 2014, Nano letters.

[19]  Uri Banin,et al.  Synthesis of Size-Selected, Surface-Passivated InP Nanocrystals , 1996 .

[20]  Justin R. Caram,et al.  Multiexciton Lifetimes Reveal Triexciton Emission Pathway in CdSe Nanocrystals. , 2018, Nano letters.

[21]  Dan Oron,et al.  Two-color antibunching from band-gap engineered colloidal semiconductor nanocrystals. , 2012, Nano letters.

[22]  Terry M. Therneau,et al.  Maximum likelihood method for the analysis of time-resolved fluorescence decay curves , 1991, European Biophysics Journal.

[23]  P. Frantsuzov,et al.  Model of fluorescence intermittency of single colloidal semiconductor quantum dots using multiple recombination centers. , 2009, Physical review letters.

[24]  M. Bawendi,et al.  Synthesis and characterization of nearly monodisperse CdE (E = sulfur, selenium, tellurium) semiconductor nanocrystallites , 1993 .

[25]  Jing Zhao,et al.  Biexciton quantum yield of single semiconductor nanocrystals from photon statistics. , 2011, Nano letters.

[26]  Philippe Guyot-Sionnest,et al.  Characterizing quantum-dot blinking using noise power spectra , 2004 .

[27]  R. A. Marcus,et al.  Explanation of quantum dot blinking without the long-lived trap hypothesis , 2005 .

[28]  O. Sauter,et al.  Facts and artifacts in the blinking statistics of semiconductor nanocrystals. , 2010, Nano letters.

[29]  E. Barkai,et al.  Nonergodicity of blinking nanocrystals and other Lévy-walk processes. , 2005, Physical review letters.

[30]  M. Frimmer,et al.  Reduced Auger recombination in single CdSe/CdS nanorods by one-dimensional electron delocalization. , 2013, Nano letters.

[31]  Monica Nadasan,et al.  Synthesis and micrometer-scale assembly of colloidal CdSe/CdS nanorods prepared by a seeded growth approach. , 2007, Nano letters.

[32]  Victor I Klimov,et al.  Auger recombination of biexcitons and negative and positive trions in individual quantum dots. , 2014, ACS nano.

[33]  P. Guyot-Sionnest,et al.  Synthesis and Characterization of Strongly Luminescing ZnS-Capped CdSe Nanocrystals , 1996 .

[34]  M Dahan,et al.  Bunching and antibunching in the fluorescence of semiconductor nanocrystals. , 2001, Optics letters.

[35]  Lucas P. Watkins,et al.  Detection of intensity change points in time-resolved single-molecule measurements. , 2005, The journal of physical chemistry. B.

[36]  J. Vela,et al.  "Giant" multishell CdSe nanocrystal quantum dots with suppressed blinking. , 2008, Journal of the American Chemical Society.

[37]  Christopher H. Hendon,et al.  Nanocrystals of Cesium Lead Halide Perovskites (CsPbX3, X = Cl, Br, and I): Novel Optoelectronic Materials Showing Bright Emission with Wide Color Gamut , 2015, Nano letters.

[38]  David J. Nesbitt,et al.  ``On''/``off'' fluorescence intermittency of single semiconductor quantum dots , 2001 .

[39]  Michel Orrit,et al.  Simple model for the power-law blinking of single semiconductor nanocrystals , 2002 .

[40]  A. Alivisatos,et al.  Continuous distribution of emission states from single CdSe/ZnS quantum dots. , 2006, Nano letters.

[41]  Weidong Yang,et al.  Shape control of CdSe nanocrystals , 2000, Nature.

[42]  C. Galland,et al.  Two types of luminescence blinking revealed by spectroelectrochemistry of single quantum dots , 2011, Nature.

[43]  P. Frantsuzov,et al.  Universality of the fluorescence intermittency in nanoscale systems: experiment and theory. , 2013, Nano letters.

[44]  Victor I. Klimov,et al.  Lifetime blinking in nonblinking nanocrystal quantum dots , 2012, Nature Communications.

[45]  Ou Chen,et al.  Compact high-quality CdSe-CdS core-shell nanocrystals with narrow emission linewidths and suppressed blinking. , 2013, Nature materials.