scholarly journals Phase Transition and Optical Properties for Ultrathin KNbO3Nanowires

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Shulin Yang ◽  
Yongming Hu ◽  
Shengfu Wang ◽  
Haoshuang Gu ◽  
Yu Wang
Keyword(s):  
Phase Transition ◽  
Optical Properties ◽  
Room Temperature ◽  
Oxygen Vacancies ◽  
Light Emission ◽  
Hydrothermal Route ◽  
Photoluminescence Study ◽  
Phase Structures ◽  
Three Phase ◽  
Visible Light Emission

Fascicular KNbO3nanowires with tetragonal perovskite structures and ultrasmall diameters are synthesized by hydrothermal route at about 150°C for 24 hours. The concentrations of medium alkalinity have influenced phase structures and the final morphologies of the products significantly by modifying the conditions in process. The as-prepared KNbO3nanowires exhibit three phase transitions at about 343, 454.7, and 623 K as the temperature increases from 250 to 700 K. The band gap is about 3.78 eV for KNbO3nanowires. Photoluminescence study at room temperature reveals two visible light emission bands peaking at ~551 and 597 nm, respectively, which may be due to the oxygen vacancies, site niobium (occupy the location of Nb), and antisite niobium (occupy the location of K) in KNbO3nanowires.

Temperature sensitive optical properties of exciton and room-temperature visible light emission from disordered Cu2O nanowires

RSC Advances ◽  
2014 ◽  
Vol 4 (71) ◽  
pp. 37542-37546 ◽  
Author(s):  
Peng Wang ◽  
Xinhong Zhao ◽  
Hairong Li ◽  
Lingshan Li ◽  
Jing Li ◽  
...  
Keyword(s):  
Optical Properties ◽  
Visible Light ◽  
White Light ◽  
Room Temperature ◽  
Light Emission ◽  
Temperature Sensitive ◽  
Excitonic Emission ◽  
First Time ◽  
Visible Light Emission

The excitonic emission of the Cu2O nanowires are demonstrated, and a visible white light is observed for the first time.

scholarly journals The Structural, Electronic, and Optical Properties of Ge/Si Quantum Wells: Lasing at a Wavelength of 1550 nm

Nanomaterials ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 1006
Author(s):  
Hongqiang Li ◽  
Jianing Wang ◽  
Jinjun Bai ◽  
Shanshan Zhang ◽  
Sai Zhang ◽  
...  
Keyword(s):  
Optical Properties ◽  
Quantum Wells ◽  
Room Temperature ◽  
Light Emission ◽  
Single Mode ◽  
Group Iv ◽  
Light Power ◽  
Fully Integrated ◽  
Electronic And Optical Properties ◽  
Novel Approach

The realization of a fully integrated group IV electrically driven laser at room temperature is an essential issue to be solved. We introduced a novel group IV side-emitting laser at a wavelength of 1550 nm based on a 3-layer Ge/Si quantum well (QW). By designing this scheme, we showed that the structural, electronic, and optical properties are excited for lasing at 1550 nm. The preliminary results show that the device can produce a good light spot shape convenient for direct coupling with the waveguide and single-mode light emission. The laser luminous power can reach up to 2.32 mW at a wavelength of 1550 nm with a 300-mA current. Moreover, at room temperature (300 K), the laser can maintain maximum light power and an ideal wavelength (1550 nm). Thus, this study provides a novel approach to reliable, efficient electrically pumped silicon-based lasers.

In2O3 Thin Films Prepared on TiAlN Substrates Using a Triethylindium and Oxygen Mixture

2007 ◽  
Vol 124-126 ◽  
pp. 1597-1600
Author(s):  
Hyoun Woo Kim ◽  
Sun Keun Hwang ◽  
Won Seung Cho ◽  
Tae Gyung Ko ◽  
Seung Yong Choi ◽  
...  
Keyword(s):  
Thin Films ◽  
Substrate Temperature ◽  
Room Temperature ◽  
Light Emission ◽  
Xrd Analysis ◽  
Oxygen Mixture ◽  
Photoluminescence Spectra ◽  
Sem Images ◽  
Room Temperature Photoluminescence ◽  
Visible Light Emission

This paper reports the fabrication of indium oxide (In2O3) films using a triethylindium and oxygen mixture. The deposition has been carried out on TiAlN substrates (200-350°C). We have established the correlation between the substrate temperature and the structural properties. The films deposited at 300-350°C were polycrystalline, whereas those deposited at 200°C was close to amorphous. XRD analysis and SEM images indicated that the films grown at 350°C had grained structures with the (222) preferred orientation. The room-temperature photoluminescence spectra of the In2O3 films exhibited a visible light emission.

Direct role of surface oxygen vacancies in visible light emission of tin dioxide nanowires

2008 ◽  
Vol 129 (24) ◽  
pp. 244710 ◽  
Author(s):  
S. Lettieri ◽  
M. Causà ◽  
A. Setaro ◽  
F. Trani ◽  
V. Barone ◽  
...  
Keyword(s):  
Visible Light ◽  
Oxygen Vacancies ◽  
Tin Dioxide ◽  
Light Emission ◽  
Surface Oxygen ◽  
Direct Role ◽  
Visible Light Emission

Correlation between structural and optical properties of Si nanocrystals embedded in SiO2: The mechanism of visible light emission

2000 ◽  
Vol 77 (20) ◽  
pp. 3143-3145 ◽  
Author(s):  
B. Garrido ◽  
M. López ◽  
O. González ◽  
A. Pérez-Rodrı́guez ◽  
J. R. Morante ◽  
...  
Keyword(s):  
Optical Properties ◽  
Visible Light ◽  
Light Emission ◽  
Structural And Optical Properties ◽  
Si Nanocrystals ◽  
Visible Light Emission

Hydrothermal Synthesis and Optical Properties of Ellipsoid-Like CeO2 Nanostructures with Rugged Surface and Many Pores

2017 ◽  
Vol 48 ◽  
pp. 95-103 ◽  
Author(s):  
Xiao Fei Niu
Keyword(s):  
Optical Properties ◽  
Hydrothermal Synthesis ◽  
Raman Scattering ◽  
Band Gap ◽  
Room Temperature ◽  
Oxygen Vacancies ◽  
Hydrothermal Technique ◽  
Pl Spectra ◽  
Cubic Structure ◽  
Rugged Surface

The almost monodisperse ellipsoid-like CeO2 nanostructures with rugged surface and many pores have been synthesized by a smart hydrothermal technique. Various techniques have been applied to investigate the CeO2 nanostructures, including XRD, SEM, XPS, Raman scattering, UV-vis and Photoluminescence (PL) spectra. The results showed that the ellipsoid-like CeO2 have a fluorite cubic structure and there are Ce3+ ions and oxygen vacancies existing in surface of samples. It is also found that there is a red-shifting in the band gap of the materials compared to bulk one, which is mainly attributed to the influences of the Ce3+ ions, oxygen vacancies and the morphology of the materials. The photoluminescence measurement indicated that the ellipsoid-like CeO2 samples exhibit excellent optical properties at room temperature, which can be reasonably explained for the influences of the concentration of oxygen vacancies and Ce3+ ions.

scholarly journals Комплексные исследования кинетики индуцированного фазового перехода в [001], [011] и [111]-ориентированных монокристаллических релаксорных твердых растворах

2018 ◽  
Vol 60 (5) ◽  
pp. 955
Author(s):  
Л.С. Камзина ◽  
Л.А. Кулакова
Keyword(s):  
Phase Transition ◽  
Optical Properties ◽  
Dielectric Properties ◽  
Electric Field ◽  
Solid Solutions ◽  
Room Temperature ◽  
Optical Transmission ◽  
Time Interval ◽  
Small Fields ◽  
Kinetics Of

AbstractThe kinetics of an induced phase transition in single-crystal relaxor solid solutions 33PbIn_1/2Nb_1/2O_3–35PbMg_1/3Nb_2/3O_3–32PbTiO_3 and PbMg_1/3Nb_2/3O_3–29PbTiO_3 under application of an electric field along three directions [001], [011], and [111] at room temperature is studied. Joint measurements of optical transmission at different wavelengths, dielectric properties, and attenuation of sound are carried out. It was found that, even in small fields ( E ~ 2 kV/cm) applied in the [011] and [111] directions, the maximum changes in all three characteristics as well as the coincidence of the time dependences of the optical transmission at different wavelengths of light occur in the same time interval. It is established that, in the same interval of fields along the [001] direction, the anomalies of the optical properties do not coincide in time with the anomalies of the acoustic and dielectric properties. The results obtained are explained by the induction of single-domain and multidomain phases.

Effects of annealing ambient on oxygen vacancies and phase transition temperature of VO2 thin films

RSC Advances ◽  
2016 ◽  
Vol 6 (83) ◽  
pp. 79383-79388 ◽  
Author(s):  
H. Y. Xu ◽  
Y. H. Huang ◽  
S. Liu ◽  
K. W. Xu ◽  
F. Ma ◽  
...  
Keyword(s):  
Thin Films ◽  
Phase Transition ◽  
Transition Temperature ◽  
Magnetron Sputtering ◽  
Direct Current ◽  
Room Temperature ◽  
Oxygen Vacancies ◽  
Dc Magnetron Sputtering ◽  
Si Substrates ◽  
Vo2 Thin Films

VO2 thin films are prepared on Si substrates by direct-current (DC) magnetron sputtering at room temperature and annealed in vacuum at different argon pressures.

Role of oxygen vacancies and interstitials on structural phase transition, grain growth, and optical properties of Ga doped TiO2

2018 ◽  
Vol 123 (24) ◽  
pp. 245702 ◽  
Author(s):  
Nasima Khatun ◽  
Saurabh Tiwari ◽  
C. P. Vinod ◽  
Chuan-Ming Tseng ◽  
Shun Wei Liu ◽  
...  
Keyword(s):  
Phase Transition ◽  
Optical Properties ◽  
Grain Growth ◽  
Structural Phase Transition ◽  
Oxygen Vacancies ◽  
Structural Phase ◽  
Doped Tio2
Sign in / Sign up

Export Citation Format

Share Document