MATERIALS RESEARCH BULLETIN
·
2018
·
IF 2.873
Kaimin Huang,Guowu Tang,Qianhang Luo,Guoquan Qian,Li Yang,Fangqiang Yuan,Zhenguo Shi,Qi Qian,Zhongmin Yang
Se 0.5 Te 0.5 semiconductor core optical fibers with phosphate glass cladding were fabricated by using a reactive molten core approach. The core was found to be amorphous with some oxygen diffusing in from the cladding glass. Crystalline Se 0.5 Te 0.5 (c-Se 0.5 Te 0.5 ) semiconductor core fibers were obtained by a post-drawing annealing process. Significant disparities in conductivity under stress and without stress were observed in c-Se 0.5 Te 0.5 semiconductor core fibers. To the best of our knowledge, this is the first time that stress sensing can be realized in c-Se 0.5 Te 0.5 semiconductor core optical fibers. This is in contrast to all previous work on stress sensing using fibers, which require the use of optical probing signals. In addition, it is found that more than 60 times change in conductivity between dark and illuminated states in c-Se 0.5 Te 0.5 semiconductor core fibers. These results demonstrate that c-Se 0.5 Te 0.5 semiconductor core optical fibers have promising applications in stress sensor, photodetector, and optical switch.
研究领域:
材料科学
·
光学工程
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2021
·Vol. 17
·期 28
·2101403
·
IF 13.281
Qiqian He,Gaoyu Chen,Yongkai Wang,Xiaoyu Liu,Danting Xu,Xiangxing Xu,Ying Liu,Jianchun Bao,Xun Wang
All-Inorganic perovskite CsPbX 3 (X = Cl, Br, I) quantum dots (QDs) have attracted tremendous attention in the past few years for their appealing performance in optoelectronic applications. Major properties of CsPbX 3 QDs include the positive photoconductivity (PPC) and the defect tolerance of the in-band trap states. Here it is reported that when hybridizing CsPbX 3 QDs with indium tin oxide (ITO) nanocrystals to form CsPbX 3 -ITO nano-heterojunctions (NHJs), a voltage tuned photoresponse—from PPC to negative photoconductivity (NPC) transform—is achieved in lateral drain-source structured ITO/CsPbX 3 -ITO-NHJs/ITO devices. A model combining exciton, charge separation, transport, and most critical the voltage driven electron filling of the in-band trap states with drain–source voltage ( V DS ) above a threshold, is proposed to understand this unusual PPC-NPC transform mechanism, which is different from that of any known nanomaterial system. This finding exhibits potentials for developing devices such as photodetectors, optoelectronic switches, and memories.
研究领域:
材料科学
·
光电子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NANOTECHNOLOGY
·
2023
·Vol. 34
·期 28
·285206
·
IF 3.5
Bo Zhang,Eli Martel,Zhenyu Wang,Jinying Zhang,Thomas Szkopek
Violet phosphorus is a semiconducting allotrope of phosphorus with a layered crystalline structure consisting of orthogonally oriented layers of phosphorus chains composed of P2[P8]P2[P9] repeating units. Here, we report optical transmission spectroscopy and photoconductivity measurements of exfoliated flakes of violet phosphorus in the thin-film bulk limit. The violet phosphorus was synthesized by chemical vapour transport, and subsequently protected from oxidation with an inert gas environment. A peak photoconductive responsivity of R = 7 mA W−1 at photon energy 2.8 eV was observed. The spectral dependence of optical transmission and photoconductivity of violet phosphorus leads us to identify optical transitions at van Hove singularities corresponding to energies E1 = 1.80 ± 0.05 eV and E2 = 1.95 ± 0.05 eV. Density functional theory was applied to the calculation of violet phosphorus (vP) bandstructure, and a dipole transition analysis shows that optical transitions at the Z and A0 points of the Brillouin zone are in agreement with experimental observations. Exposure to ambient environmental conditions for several minutes is sufficient to significantly reduce vP photoconductivity, while longer exposure leads to blistering due to oxidation. Thus, a locally inert chemical environment is essential to accessing vP intrinsic optoelectronic properties.
研究领域:
材料科学
·
光学
·
凝聚态物理
✓ 已验证
DOI
高影响因子
Small
·
2023
·Vol. 20
·期 21
·2309626
·
IF 13.3
Boyu Xu,Dan Guo,Weikang Dong,Huiying Gao,Peng Zhu,Zhiwei Wang,Kenji Watanabe,Takashi Taniguchi,Zhaochu Luo,Fawei Zheng,Shoujun Zheng,Jiadong Zhou
Floating gate memory (FGM), composed of van der Waals (vdW) junctions with an atomically thin floating layer for charge storage, is widely employed to develop logic-in memories and in-sensor computing devices. Most research efforts of FGM are spent on achieving long-term charge storage and fast reading/writing for flash and random-access memory. However, dynamic modulation of memory time via a tunneling barrier and vdW interfaces, which is critical for synaptic computing and machine vision, is still lacking. Here, a van der Waals short-term memory with tunable memory windows and retention times from milliseconds to thousands of seconds is reported, which is approximately exponentially proportional to the thickness h-BN (hexagonal boron nitride) barrier. The specific h-BN barrier with fruitful gap states provides charge release channels for trapped charges, making the vdW device switchable between positive photoconductance and negative photoconductance with a broadband light from IR to UV range. The dynamic short-term memory with tunable photo response highlights the design strategy of novel vdW memory vis interface engineering for further intelligent information storage and optoelectronic detection.
研究领域:
材料科学
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电子工程
·
光电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2017
·
IF 3.133
Wen Wu,Manjing Wang,Limin Liang,Yufei Yan,Xuerong Zheng,Qiuyan Hao,Hui Liu,Jun Zhang,Caichi Liu
The length effects on photoconductivity have been observed in Sb 2 Se 3 nanorods with uniform diameter grown by a hot-injection polyol process. The phase formation and morphology evolution of Sb 2 Se 3 nanorods were investigated by XRD and TEM analysis. By changing the reaction temperature from 150 °C to 250 °C, the sizes and aspect ratios of Sb 2 Se 3 nanorods can be easily controlled, with an average length ranged from 0.6 μm to 3.2 μm. The length-controlled nanorods were directly used for fabricating prototype photodetectors to explore their length-dependence performances. A significant increase of photoresponse with length elongation has been observed, in which the optimal device displays a remarkable response to simulated solar light with a high switching “on/off” ratio of 320, short response/recovery times (0.15/0.16 s) and long-term durability. This length-dependence property on photodetectors can be considered as an important step to promote the performance of 1D Sb 2 Se 3 nanomaterials .
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
2D Materials
·
2024
·Vol. 11
·期 2
·025024
·
IF 4.5
Bo Zhang,Yunjie Liu,Bing Hu,Fuhai Guo,Mingcong Zhang,Siqi Li,Weizhuo Yu,Lanzhong Hao
Due to its large absorption coefficient and high carrier mobility, SnS exhibits strong promise in the area of optoelectronic devices. Nevertheless, the fabrication of large-area, high-quality films for SnS photodetectors (PDs) with superior photoresponse remains a formidable task, seriously limiting its further practical application. In the present study, we report a superior-performance broadband PD founded on the epitaxial SnS film. Large-area uniform SnS films were grown epitaxially on (100)-oriented KBr using magnetron sputtering technique, further exfoliated, and transferred in a wafer size to fabricated two-ends PD devices. Benefitting from high crystallization and unique photoconductive-bolometric coupling effect, the two modes of operation exhibit a wide range of spectral responses from the visible to near-infrared wavelength (405–1920 nm). Particularly noteworthy is the SnS device fabricated, which demonstrates an impressive responsivity of 95.5 A W−1 and a detectivity of 7.8 × 1011 Jones, outperforming other devices by 1–2 orders of magnitude. In addition, SnS PD shows excellent environmental durability. This work provides a robust approach to develop high-performance broadband SnS PDs, while simultaneously offering deep insight into the light–matter interactions.
研究领域:
材料科学
·
光学工程
·
半导体物理
✓ 已验证
产品关联
DOI
高影响因子
Applied Physics Express
·
2020
·Vol. 13
·期 7
·071004
·
IF 3.086
Dou Zhao,Xin Liu,Jingyi Yu,Meng Xu,Binbin Zhang,Yadong Xu,Wanqi Jie
A photoconductive gain (up to 400%) is observed in a 4-hydroxycyanobenzene (4HCB, C7H5NO) bulk organic semiconducting detector, resulting in a high sensitivity of 38.8 μC Gyair−1 s−1 cm−2 under 50 kVp X-ray beam irradiation. The gain variation tendency as the function of both the applied bias voltage and the incident X-ray dose rate is revealed. A rising stage at the gain versus dose rate curve is observed at the low-flux range of X-ray irradiation, attributed to the trap-filling process. A deep-trapping dependent model is proposed, in which the hole injection assisted by trapped electrons is responsible for the gain.
研究领域:
材料科学
·
辐射探测
✓ 已验证
DOI
PubMed
高影响因子
Scientific Reports
·
2023
·Vol. 13
·期 1
·1-9
·
IF 4.6
Zhang Yige,Xie Xiaowen,Liu Jianliang,Tang Boyuan,Fang Can,Liu Xiaoming,Dai Zhifeng,Xiong Yubing
Stimulus-responsive ionic liquids have gained significant attention for their applications in various areas. Herein, three kinds of azobenzimidazole ionic liquids with reversible photo-induced conductivity regulation were designed and synthesized. The change of electrical conductivity under UV/visible light irradiation in aqueous solution was studied, and the effect of chemical structure and concentration of ionic liquids containing azobenzene to the regulation of photoresponse conductivity were discussed. The results showed that exposing the ionic liquid aqueous solution to ultraviolet light significantly increased its conductivity. Ionic liquids with longer alkyl chains exhibited an even greater increase in conductivity, up to 75.5%. Then under the irradiation of visible light, the electrical conductivity of the solution returned to its initial value. Further exploration of the mechanism of the reversible photo-induced conductivity regulation of azobenzene ionic liquids aqueous solution indicated that this may attributed to the formation/dissociation of ionic liquids aggregates in aqueous solution induced by the isomerization of azobenzene under UV/visible light irradiation and resulted the reversible conductivity regulation. This work provides a way for the molecular designing and performance regulation of photo-responsive ionic liquid and were expected to be applied in devices with photoconductive switching and micro photocontrol properties.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Chunli Diao,Hanxing Liu,Hua Hao,Minghe Cao,Zhonghua Yao,Haiwu Zheng
SrTiO 3 /BaTiO 3 (ST/BT) thin-film heterostructure was deposited on Pt/Ti/SiO 2 /Si(100) substrate by spin-coating. X-ray diffraction pattern shows that the heterostructure is a perovskite structure composed of ST and BT without any impurity peaks. The dielectric constant and loss of the heterostructure at 10 kHz are 704 and 0.024, respectively. The electric-field dependence of dielectric response was investigated and the tunability of the sample under 200 kV/cm applied field is 21.5%. Compared with pure ST thin film , the polarization-electric field loops of ST/BT heterostructure display high polarization and good symmetry, which could be attributed to the introduction of BT with high dielectric constant and inhibition of the potential pitfalls movement for high barrier at ST/BT interface. Moreover, the heterostructure demonstrates photoconductivity behavior with 405 nm light illumination. The results indicate that ST/BT heterostructure is a potential material in application as multifunctional photoelectric devices.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2017
·
IF 5.401
Zhongming Wang,Kun Wang,Xiaoying Peng,Qiang Geng,Xun Chen,Wenxin Dai,Xianzhi Fu,Xuxu Wang
The photoconductivity and the gas sensing property of TiO 2 at room temperature under ultraviolet (UV) irradiation were compared with those under visible light irradiation (≥420 nm), respectively. It was found that UV light could cause the photoconductivity of TiO 2 and its sensing response to both ethylene and oxygen, while the visible light at 420 nm could cause the photoconductivity of TiO 2 and its sensing response to oxygen but not to ethylene. This indicates that the photo-assisted gas sensing performance of TiO 2 was dependent on its light-excited behavior: The intrinsic excitation of TiO 2 induced by UV light could produce both the holes and electrons, which exhibited a respective response to ethylene and oxygen, while the extrinsic excitation of TiO 2 induced by visible light maybe only produced the free electrons but not free holes, resulting in only a response to oxygen. Furthermore, it was found that the visible-light enhanced conductivity maybe depend on the Ti–bonded hydroxyls (Ti–OH) at TiO 2 surface. With the removal of Ti–OH by increasing temperature, the visible light could not produce the photoconductivity of TiO 2 . It was proposed that Ti–OH groups act as the shallow trapped level to cause the extrinsic excitation of TiO 2 .
研究领域:
材料科学
·
半导体物理
·
传感器技术
·
光化学
·
表面科学
·
纳米材料
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2017
·
IF 4.536
Weien Lai,Peng Huang,Beatriz Pelaz,Pablo del Pino,Qian Zhang
We present an all-optical modulator based on manganese ferrite nanoparticles (MnFe2O4 NPs), which provides an enhanced attenuation of broad-band terahertz waves. A wide-band modulation of THz transmission was observed in a frequency range from 0.15 to 1.2 THz. The experimental results were assessed by simulations in the context of a band structure model of semiconductors. Our work demonstrated that coatings of MnFe2O4 NPs can be efficiently used to improve the performance of THz modulators based on optical modulation. This paper describes a new route to increase the surface photoconductivity of semiconductors by coating of MnFe2O4 NPs. This work demonstrates that the THz modulator based on MnFe2O4 NPs can significantly boost the overall performance of THz communication systems, and MnFe2O4 NPs may offer some useful solutions for future THz devices.
研究领域:
材料科学
·
光学工程
·
半导体物理
✓ 已验证
产品关联
DOI
高影响因子
Crystals
·
2022
·Vol. 12
·期 10
·1425
·
IF 2.67
Zijie Xiao,Tingting Tao,Jingting Shu,Wei Dang,Shusheng Pan,Wei Zhang
Studying the carrier recombination process in MAPb(Br1−yIy)3single crystals (SCs) is important for its application in the optoelectronic field. In this work, a series of MAPb(Br1−yIy)3SCs with varied Br/I compositions have been studied. Steady-state photoluminescence (PL) spectra, time-resolved photoluminescence (TRPL) spectra and time-resolved microwave photoconductivity (TRMC) were used to understand the radiative and non-radiative recombination processes of MAPb(Br1−yIy)3SCs. By comparing the dynamics of TRPL and TRMC, we conclude that the dynamics of TRPL is dominated by the electron trapping process, which is in accordance with the fast decay component of TRMC kinetics, whereas the slower decay component in TRMC is dominated by the hole trapping process. Moreover, we find both the electron and hole trapping rates in mixed-halide perovskite MAPb(Br1−yIy)3(0 < y < 1) SCs are higher than that of mono-halide perovskite MAPbBr3SCs and MAPbI3SCs. This suggests mixed-halide crystals could introduce additional electron and hole trapping densities, which could be related to the fluctuation of Br/I compositions in the crystals. This work is helpful for understanding carrier recombination process in mixed-halide perovskite SCs.
研究领域:
材料科学
·
光学
·
半导体物理
✓ 已验证
DOI
高影响因子
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