Spectral diffusion (SD) represents a substantial obstacle toward implementation of solid-state quantum emitters as a source of indistinguishable photons. By performing high-resolution emission spectroscopy for individual colloidal quantum dots at cryogenic temperatures, we prove the causal link between the quantum-confined Stark effect and SD. Statistically analyzing the wavelength of emitted photons, we show that increasing the sensitivity of the transition energy to an applied electric field results in amplified spectral fluctuations. This relation is quantitatively fit to a straightforward model, indicating the presence of a stochastic electric field on a microscopic scale, whose standard deviation is 9 kV/cm, on average. The current method will enable the study of SD in multiple types of quantum emitters such as solid-state defects or organic lead halide perovskite quantum dots, for which spectral instability is a critical barrier for applications in quantum sensing.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC10636921 | PMC |
http://dx.doi.org/10.1021/acs.nanolett.3c02318 | DOI Listing |
Langmuir
December 2024
Department of Physics, National Institute of Technology, Jamshedpur-831014, India.
We have conducted a systematic study employing density functional theory (DFT) and quantum theory of atoms in molecules (QTAIM) to explore the gas sensing capabilities of nitrogen-doped single vacancy graphene quantum dots (SV/3N) decorated with transition metals (TM = Mn, Co, Cu). We have studied the interactions between TM@SV/3N and four different target gases (AsH, NH, PH, and HS) through the computation of adsorption energies, charge transfer, noncovalent interaction, density of states, band gap, and work function for 12 distinct adsorption systems. Our comprehensive analysis included an in-depth assessment of sensors' stability, sensitivity, selectivity, and reusability for practical applications.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2024
University of Science and Technology of China, Hefei National Research Center for Physical Sciences at Microscale, jinzhai road, hefei, CHINA.
Herein, we first report a photocatalytic OCM using CO2 as a soft oxidant for C2H6 production under mild conditions, where an efficient photocatalyst with unique interface sites is constructed to facilitate CO2 adsorption and activation, while concurrently boosting CH4 dissociation. As a prototype, the Au quantum dots anchored on oxygen-deficient TiO2 nanosheets are fabricated, where the Au-Vo-Ti interface sites for CO2 adsorption and activation are collectively disclosed by in situ Kelvin probe force microscopy, quasi in situ X-ray photoelectron spectroscopy and theoretical calculations. Compared with single metal site, the Au-Vo-Ti interface sites exhibit the lower CO2 adsorption energy and decrease the energy barrier of the *CO2 hydrogenation step from 1.
View Article and Find Full Text PDFMikrochim Acta
December 2024
State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, 214122, China.
A dual-signal aptamer-based assay utilizing colorimetric and fluorescence techniques was developed for the determination of zearalenone (ZEN). The CdTe quantum dots, serving as the fluorescent signal source, were surface-modified onto FeO@SiO and subsequently functionalized with the aptamer. The COF-Au was modified with complementary chain, which possessed peroxide (POD)-like enzyme properties, and could catalyze the peroxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to ox TMB, resulting in the generation of colorimetric signals.
View Article and Find Full Text PDFJ Tissue Viability
December 2024
Institute of Nanoscience & Nanotechnology, Kafrelsheikh University, Kafr ElSheikh, 33516, Egypt; Nile Valley University, Fayoum, 63518 Egypt. Electronic address:
Despite the advances in the development of therapeutic wearable wound-healing patches, lack self-healing properties and strong adhesion to diabetic skin, hindering their effectiveness. We propose a unique, wearable patch made from a 3D organo-hydrogel nanocomposite containing polydopamine, titanium dioxide nanoparticles, and silver quantum dots (PDA-TiO@Ag). The designed patch exhibits ultra-stretchable, exceptional-self-healing, self-adhesive, ensuring conformal contact with the skin even during movement.
View Article and Find Full Text PDFMikrochim Acta
December 2024
School of Life and Environmental Sciences, School of Intellectual Property, Guilin University of Electronic Technology, Guilin, Guangxi, 541004, People's Republic of China.
A novel carbon-based light-addressable potentiometric aptasensor (C-LAPS) was constructed for detection low-density lipoprotein (LDL) in serum. Carboxylated TiC MXene @reduced graphene oxide (C-MXene@rGO) was used as interface and o-phenylenediamine functionalized nitrogen-doped graphene quantum dots (OPD@NGQDs) as the photoelectric conversion element. The photosensitive layers composed of OPD@NGQDs/C-MXene@rGO exhibit superior photoelectric conversion efficiency and excellent biocompatibility, which contribute to an improved response signal.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!