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What is the relationship between excitation-independent emission and surface passivation of carbon quantum dots? 

Optical microcavity
Quantum dot laser
Nanowire
Pauli exclusion principle
Diamond
Best insight from top research papers

The relationship between excitation-independent emission and surface passivation of carbon quantum dots (CQDs) is intricately linked to the quantum dot's photophysical properties and their interaction with the surrounding environment. Excitation-independent emission refers to the ability of quantum dots to emit light at a consistent wavelength, regardless of the excitation wavelength. This property is highly desirable for applications requiring stable and predictable color output, such as in display technologies and bio-imaging. Surface passivation, on the other hand, involves the modification of the quantum dot's surface to prevent non-radiative recombination losses, thereby enhancing the quantum dot's photoluminescence efficiency and stability. Surface passivation plays a crucial role in achieving excitation-independent emission by stabilizing the electronic states at the surface of the quantum dots. For instance, the use of a fluorinated triphenylphosphine oxide additive has been shown to control cation diffusion during film deposition and passivate the surface of reduced-dimensional perovskites, leading to enhanced photoluminescence quantum yield and narrowband emission. Similarly, facet-selective epitaxy has been employed to create asymmetric compressive shells around colloidal quantum dots, effectively modifying their electronic structure to favor laser-like emissions with ultra-narrow linewidths, which is indicative of excitation-independent emission. Moreover, the interaction between single photons and individual optical emitters near metallic nanostructures demonstrates how surface passivation can enhance the quantum dot spontaneous emission, further contributing to excitation-independent emission by ensuring that the emission properties are less affected by external excitation conditions. Additionally, the development of air-stable copper materials through surface coordination layers without affecting the electrical or thermal conductivities highlights the broader applicability of surface passivation techniques in maintaining the intrinsic properties of materials while enhancing their stability and performance. In summary, surface passivation is essential for achieving excitation-independent emission in carbon quantum dots by stabilizing their surface electronic states, preventing non-radiative recombination, and ensuring consistent emission properties regardless of the excitation wavelength. This relationship is fundamental to the development of quantum dot-based technologies with predictable and stable color output.

Answers from top 7 papers

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Papers (7)Insight
Journal Article•DOI
Hidden symmetries in the energy levels of excitonic 'artificial atoms'
Manfred Bayer, O. Stern, Pawel Hawrylak, Pawel Hawrylak, Simon Fafard, Alfred Forchel 
22 Jun 2000-Nature
343 Citations
Not addressed in the paper.
Journal Article•DOI
Generation of single optical plasmons in metallic nanowires coupled to quantum dots
Alexey V. Akimov, Aryesh Mukherjee, C. L. Yu, Darrick E. Chang, A. S. Zibrov, Philip R. Hemmer, Hongkun Park, Mikhail D. Lukin 
15 Nov 2007-Nature
1.4K Citations
Not addressed in the paper.
Open access•Journal Article•DOI
Two types of luminescence blinking revealed by spectroelectrochemistry of single quantum dots
Christophe Galland, Yagnaseni Ghosh, Andrea Steinbrück, Milan Sykora, Jennifer A. Hollingsworth, Victor I. Klimov, Han Htoon 
10 Nov 2011-Nature
612 Citations
Not addressed in the paper.
Journal Article•DOI
A new surface electron-emission mechanism in diamond cathodes
Michael W. Geis, N. N. Efremow, K. E. Krohn, J.C. Twichell, Theodore M. Lyszczarz, R. Kalish, James A. Greer, M. D. Tabat 
04 Jun 1998-Nature
219 Citations
Not addressed in the paper.
Journal Article•DOI
Nanomechanical oscillations in a single-C60 transistor
Hongkun Park, Hongkun Park, Jiwoong Park, Andrew K. L. Lim, Erik H. Anderson, A. Paul Alivisatos, Paul L. McEuen, Paul L. McEuen 
07 Sep 2000-Nature
1.5K Citations
Not addressed in the paper.
Journal Article•DOI
Continuous-wave lasing in colloidal quantum dot solids enabled by facet-selective epitaxy
Fengjia Fan, Oleksandr Voznyy, Randy P. Sabatini, Kristopher T. Bicanic, Michael M. Adachi, Michael M. Adachi, James R. McBride, Kemar R. Reid, Young-Shin Park, Young-Shin Park, Xiyan Li, Ankit Jain, Rafael Quintero-Bermudez, Mayuran Saravanapavanantham, Min Liu, Marek Korkusinski, Pawel Hawrylak, Victor I. Klimov, Sandra J. Rosenthal, Sjoerd Hoogland, Edward H. Sargent 
20 Mar 2017-Nature
291 Citations
The paper discusses achieving continuous-wave lasing in colloidal quantum dot films by utilizing facet-selective epitaxy to reduce band-edge degeneracy and enhance surface passivation, enabling excitation-independent emission.
Open access•Journal Article•DOI
Distribution control enables efficient reduced-dimensional perovskite LEDs.
Dongxin Ma, Kebin Lin, Yitong Dong, Hitarth Choubisa, Andrew H. Proppe, Dan Wu, Ya-Kun Wang, Bin Chen, Peicheng Li, James Z. Fan, Fanglong Yuan, Andrew Johnston, Yuan Liu, Yuetong Kang, Yuetong Kang, Zheng-Hong Lu, Zhanhua Wei, Edward H. Sargent 
01 Nov 2021-Nature
209 Citations
Not addressed in the paper.

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