Exploiting valence band mapping and select blue-green and red phosphorescence decay of γ-irradiated nanoscale Eu3+: Gd2O3 below concentration quenching

AbstractEuropium-doped hexagonal-mesostructured and nanotubular yttrium oxides templated by dodecylsulfate species as well as surfactant free bulk oxides were synthesized by the homogeneous precipitation method. All the as grown nanostructured or bulk materials with amorphous or poorly crystalline frameworks showed weak luminescence bands at room temperature. On calcination at 1000°C these materials were converted into highly crystalline yttrium oxides, resulting in a total increase in intensity of all the bands by one order of magnitude. In the hexagonal-mesostructured system, the main band due to the 5D0-7F2 transition for the calcined phases showed a sharp but asymmetrical multiplet splitting indicating multiple Eu sites. Concentration quenching was found at a Eu content of 3 mol% or above for these phases. In contrast, the main emission for the calcined solids in the nanotubular system occurred as poorly resolved broad band and the intensity of the main band at higher Eu content was significantly enhanced compared with those for the other two systems.

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Effects of Giant Optical Anisotropy in R-plane GaN/AlGaN Quantum Wells by Valence Band Mixing

PIERS Online ◽

10.2529/piers060801054904 ◽

2006 ◽

Vol 2 (6) ◽

pp. 562-566 ◽

Cited By ~ 2

Author(s):

Chun-Nan Chen ◽

Kao-Feng Yarn ◽

Win Jet Luo ◽

Jih-Chen Chiang ◽

Ikai Lo ◽

...

Keyword(s):

Quantum Wells ◽

Valence Band ◽

Optical Anisotropy ◽

Band Mixing ◽

Valence Band Mixing

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Erratum: Observation of monolayer valence band spin-orbit effect and induced quantum well states in MoX2

Nature Communications ◽

10.1038/ncomms6136 ◽

2014 ◽

Vol 5 (1) ◽

Cited By ~ 4

Author(s):

Nasser Alidoust ◽

Guang Bian ◽

Su-Yang Xu ◽

Raman Sankar ◽

Madhab Neupane ◽

...

Keyword(s):

Quantum Well ◽

Valence Band ◽

Spin Orbit ◽

Quantum Well States

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Oxidation of W(110): valence-band and W(4f) core-level spectroscopy

Surface Science ◽

10.1016/0039-6028(94)90812-5 ◽

1994 ◽

Vol 312 (1-2) ◽

pp. 151-156 ◽

Cited By ~ 23

Author(s):

Charles H.F. Peden ◽

Neal D. Shinn

Keyword(s):

Valence Band ◽

Core Level

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Attosecond intra-valence band dynamics and resonant-photoemission delays in W(110)

Nature Communications ◽

10.1038/s41467-021-23650-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

S. Heinrich ◽

T. Saule ◽

M. Högner ◽

Y. Cui ◽

V. S. Yakovlev ◽

...

Keyword(s):

Valence Band ◽

Photoelectron Spectroscopy ◽

Electronic Band Structure ◽

Photoelectric Effect ◽

Final State ◽

Electronic Band ◽

Time Resolved ◽

Resonant Photoemission ◽

Pulse Trains ◽

Electron Correlation Effects

AbstractTime-resolved photoelectron spectroscopy with attosecond precision provides new insights into the photoelectric effect and gives information about the timing of photoemission from different electronic states within the electronic band structure of solids. Electron transport, scattering phenomena and electron-electron correlation effects can be observed on attosecond time scales by timing photoemission from valence band states against that from core states. However, accessing intraband effects was so far particularly challenging due to the simultaneous requirements on energy, momentum and time resolution. Here we report on an experiment utilizing intracavity generated attosecond pulse trains to meet these demands at high flux and high photon energies to measure intraband delays between sp- and d-band states in the valence band photoemission from tungsten and investigate final-state effects in resonant photoemission.

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Structure, Luminescence, and Magnetic Properties of Crystalline Manganese Tungstate Doped with Rare Earth Ion

Materials ◽

10.3390/ma14133717 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3717

Author(s):

Jae-Young Jung ◽

Soung-Soo Yi ◽

Dong-Hyun Hwang ◽

Chang-Sik Son

Keyword(s):

Magnetic Field ◽

Rare Earth ◽

Sintering Temperature ◽

Luminescent Properties ◽

Concentration Quenching ◽

Rare Earth Ions ◽

Precipitation Method ◽

Rare Earth Ion ◽

Co Precipitation ◽

Quenching Phenomenon

The precursor prepared by co-precipitation method was sintered at various temperatures to synthesize crystalline manganese tungstate (MnWO4). Sintered MnWO4 showed the best crystallinity at a sintering temperature of 800 °C. Rare earth ion (Dysprosium; Dy3+) was added when preparing the precursor to enhance the magnetic and luminescent properties of crystalline MnWO4 based on these sintering temperature conditions. As the amount of rare earth ions was changed, the magnetic and luminescent characteristics were enhanced; however, after 0.1 mol.%, the luminescent characteristics decreased due to the concentration quenching phenomenon. In addition, a composite was prepared by mixing MnWO4 powder, with enhanced magnetism and luminescence properties due to the addition of dysprosium, with epoxy. To one of the two prepared composites a magnetic field was applied to induce alignment of the MnWO4 particles. Aligned particles showed stronger luminescence than the composite sample prepared with unsorted particles. As a result of this, it was suggested that it can be used as phosphor and a photosensitizer by utilizing the magnetic and luminescent properties of the synthesized MnWO4 powder with the addition of rare earth ions.

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Investigation of Band Alignment for Hybrid 2D-MoS2/3D-β-Ga2O3 Heterojunctions with Nitridation

Nanoscale Research Letters ◽

10.1186/s11671-019-3181-x ◽

2019 ◽

Vol 14 (1) ◽

Cited By ~ 1

Author(s):

Ya-Wei Huan ◽

Ke Xu ◽

Wen-Jun Liu ◽

Hao Zhang ◽

Dmitriy Anatolyevich Golosov ◽

...

Keyword(s):

Valence Band ◽

Transition Metal Dichalcogenides ◽

Three Dimensional ◽

Optoelectronic Devices ◽

Band Alignment ◽

Band Offsets ◽

Group Iii ◽

Nanoelectronic Devices ◽

Metal Dichalcogenides ◽

Band Alignments

AbstractHybrid heterojunctions based on two-dimensional (2D) and conventional three-dimensional (3D) materials provide a promising way toward nanoelectronic devices with engineered features. In this work, we investigated the band alignment of a mixed-dimensional heterojunction composed of transferred MoS2 on β-Ga2O3($$ 2- $$2-01) with and without nitridation. The conduction and valence band offsets for unnitrided 2D-MoS2/3D-β-Ga2O3 heterojunction were determined to be respectively 0.43 ± 0.1 and 2.87 ± 0.1 eV. For the nitrided heterojunction, the conduction and valence band offsets were deduced to 0.68 ± 0.1 and 2.62 ± 0.1 eV, respectively. The modified band alignment could result from the dipole formed by charge transfer across the heterojunction interface. The effect of nitridation on the band alignments between group III oxides and transition metal dichalcogenides will supply feasible technical routes for designing their heterojunction-based electronic and optoelectronic devices.

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