Pressure dependence of the near-band-edge photoluminescence from ZnO microrods at low temperature

Su, Fenghua; Wang, Wen Jie; Ding, Kan; Li, Guo Hua; Liu, Yuangfang; Joly, Alan G.; Chen, Wei

doi:10.1016/j.jpcs.2006.06.017

Cited by 14 publications

(6 citation statements)

References 21 publications

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“…From the fitting results, figure 5 plots the peak energy of the FX corresponding to the different positions along the bent nanowire. In contrast to the normal pressure-induced blue-shift [28][29][30], an obvious redshift can be observed for the near-band-edge FX emission. In this case, we proposed that a uniaxial tensile strain can be dominant when a bending deformation is applied on the ZnO nanowire, which is in good agreement with our Raman measurement and theoretical predictions from [7].…”

Section: Resultsmentioning

confidence: 84%

Localized suppression of longitudinal-optical-phonon–exciton coupling in bent ZnO nanowires

et al. 2010

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Using confocal micro-Raman and photoluminescence spectroscopy, we studied bending effects on optical properties of individual ZnO nanowires. Raman spectroscopy shows that local tensile strain can be introduced by bending the nanowire. The strain is expected to reduce the band gap on the bent part and modify the local phonon-exciton interaction. The corresponding micro-photoluminescence spectra indicate local suppression of the longitudinal-optical (LO) phonon-exciton interaction, which is determined by the intensity ratio of the second-order LO-phonon replica of the free exciton (FX-2LO) to the first-order process (FX-1LO). Our results may provide insight into the modulation of local electrical and optical properties by deforming the nanostructures.

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Section: Resultsmentioning

confidence: 84%

Localized suppression of longitudinal-optical-phonon–exciton coupling in bent ZnO nanowires

et al. 2010

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“…Furthermore, it also implies that the multifield-coupling effect indeed occurs only in the surface skin, but this effect can be omitted for larger particle sizes. The relationship between E G and the energy of the free exciton ( E FX ) and its n th longitudinal optic (LO) phonon replicas can be expressed as E FX- n LO = E G + 3 / 2 k B T − n ℏω LO , where k B is the Boltzmann constant, ℏω LO represents the LO phonon energy, and ℏω LO = 72 meV . The application of pressure increases the binding energy of a shallow exciton arising from an increase of electron effective mass and a decrease in dielectric constant as the E G increases.…”

Section: Resultsmentioning

confidence: 99%

“…(a) Theoretical (solid) reproduction of the measured pressure dependence of E G for ZnO at a variety of sizes and temperatures. The experimental data are sourced from refs −; and (b) the measured pressure dependence of E FX- n LO at 70 K. The experimental data are sourced from the ref .…”

Section: Resultsmentioning

confidence: 99%

“…The bandgap ( E G ), PL ( E PL ), and PA ( E PA ) energies of ZnO nanocrystals, − nanorods, , nanobelts, and nanofilms increase when the size diminishes or the shape is changed from one-dimension to three-dimensions for the same feature size. Moreover, the PL, PA, and E G of ZnO nanostructures undergo blue shift with decreasing temperatures − or increasing external pressure. − A number of theoretical models have been developed to study the size-induced blue shift of PL, PA, and E G in ZnO nanostructures including the quantum confinement, , color centers, free-exciton collision, surface states, , and Burstein−Moss effect, as well as the classical thermodynamic approach. , These models explained reasonably well the PL blue shift but not for both the PL and the PA simultaneously. The thermally and mechanically induced E G shift were usually fitted by using the following empirically quadratic functions: ,, E G ( T ) = E G ( 0 ) − A T 2 / ( B + T ) E G ( P ) = E G ( 0 ) + C P + D P 2 where E G (0) is bandgap at 0...…”

Section: Introductionmentioning

confidence: 99%

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Bandgap Modulation in ZnO by Size, Pressure, and Temperature

Yang

Zhou

et al. 2010

J. Phys. Chem. C

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The effect of crystal size, pressure, temperature, and their coupling on the bandgap (E G ) of ZnO crystals have been investigated based on the Hamiltonian perturbation, using the extended BOLS correlation theory. The functional dependence of the E G on the identities (order, nature, length, energy) of the representative bond for a specimen and the response of the bonding identities to the applied stimuli have been established. Theoretical reproduction of the measurements confirms that the E G expansion originates from the bond contraction/compression and bond strength gain due to (i) Goldschmidt-Pauling's rule of bond contraction induced by undercoordination, (ii) low-temperature enhanced stability, and (iii) mechanical energy storage. It is found that the multiple-field coupling effect dominates in the surface skin up to three atomic layers. The presented approach provides a guideline for harnessing the photoluminescence, photoabsorption, and exciton emission from ZnO and other semiconductors as well.

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“…The 0D ZnO materials include quantum dots (QDs), − nanoparticles, , nanoballs, , etc. The 0D ZnO nanostructure is a kind of new high functional fine inorganic material oriented toward the 21st century which shows a lot of special properties, such as migration, fluorescent, piezoelectric, absorption and scattering capacities in the UV range, etc., in the light, electricity, magnetic, and sensitive aspects of application, such as manufacturing gas and biological sensors, spintronics, phosphors, rheostats, UV shielding materials, image recording materials, piezoelectric materials, varistors, efficient catalysts, magnetic materials, and laser protection materials. , The 1D ZnO nanostructure materials include nanorods, − nanotubes, − nanowires (NWs), − nanobelts,…”

Section: Introductionmentioning

confidence: 99%

Size and Morphology Modulation in ZnO Nanostructures for Nonlinear Optical Applications: A Review

Wang

Shi

Yao

et al. 2023

ACS Appl. Nano Mater.

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Morphology-rich ZnO as a direct band gap II−VI semiconductor is a promising material for photonic, optical, and electronic devices. Nanostructured materials have provided a leading edge to the next-generation technology due to their distinguished performances and efficiencies for device fabrication. The nonlinear optical (NLO) properties and mechanisms dependent on the size and dimensionality of ZnO nanostructures remain to be elucidated. Herein, we begin to provide a comprehensive summary of the status of research activities in ZnO nanostructures, including their syntheses and potential applications, with an emphasis on multidimensional ZnO nanostructure based growth, properties, and applications. Density functional theory calculations confirmed the effect of ZnO size, morphology, and defect on the structure, work function, and charge density distribution of the electron band. Finite difference time domain simulation confirmed that the electric field, magnetic field, and Poynting vector of the ZnO system with the morphology changes were applied. Moreover, the ultrafast NLO and carrier dynamics of feature-rich ZnO nanostructures were studied. The effects of different experimental parameters on the morphology and linear and nonlinear excitation and radiation mechanisms of ZnO nanostructures were studied by constructing an electron transfer mechanism diagram and the Z-scan technique. The results show that the properties and properties of ZnO nanostructures can be regulated and controlled by the structure and morphology. The application and performance of feature-rich zinc oxide nanostructures in photoelectric functional devices are prospected, which will provide valuable references and guidance for related researchers.

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Pressure dependence of the near-band-edge photoluminescence from ZnO microrods at low temperature

Cited by 14 publications

References 21 publications

Localized suppression of longitudinal-optical-phonon–exciton coupling in bent ZnO nanowires

Localized suppression of longitudinal-optical-phonon–exciton coupling in bent ZnO nanowires

Bandgap Modulation in ZnO by Size, Pressure, and Temperature

Size and Morphology Modulation in ZnO Nanostructures for Nonlinear Optical Applications: A Review

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