The Experts below are selected from a list of 228 Experts worldwide ranked by ideXlab platform
D. Roditchev - One of the best experts on this subject based on the ideXlab platform.
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Avalanche Breakdown in GaTa_4Se_8−xTe_x narrow-gap Mott insulators
Nature Communications, 2013Co-Authors: V. Guiot, L. Cario, E. Janod, B. Corraze, M. Rozenberg, P. Stoliar, T. Cren, Vinh Ta Phuoc, D. RoditchevAbstract:Mott transitions induced by strong electric fields are receiving growing interest. Recent theoretical proposals have focused on the Zener dielectric Breakdown in Mott insulators. However, experimental studies are still too scarce to conclude about the mechanism. Here we report a study of the dielectric Breakdown in the narrow-gap Mott insulators GaTa_4Se_8− x Te_ x . We find that the I–V characteristics and the magnitude of the threshold electric field ( E _th) do not correspond to a Zener Breakdown, but rather to an avalanche Breakdown. E _th increases as a power law of the Mott–Hubbard gap ( E _g), in surprising agreement with the universal law E _th E _g^2.5 reported for avalanche Breakdown in semiconductors. However, the delay time for the avalanche that we observe in Mott insulators is over three orders of magnitude greater than in conventional semiconductors. Our results suggest that the electric field induces local insulator-to-metal Mott transitions that create conductive domains that grow to form filamentary paths across the sample. Dielectric Breakdown in Mott insulators induced by strong electric fields is thought to take place via a Zener mechanism. Guiot et al . show that the Breakdown characteristics are instead similar to the avalanche Breakdown in conventional semiconductors, although with much longer delay times.
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Resistive switching induced by electronic avalanche Breakdown in GaTa$_4$Se$_{8-x}$Te$_x$ narrow gap Mott Insulators
Nature Communications, 2013Co-Authors: V. Guiot, L. Cario, E. Janod, B. Corraze, M. Rozenberg, P. Stoliar, T. Cren, Vinh Ta Phuoc, D. RoditchevAbstract:Mott transitions induced by strong electric fields are receiving a growing interest. Recent theoretical proposals have focused on the Zener dielectric Breakdown in Mott insulators, however experimental studies are still too scarce to conclude about the mechanism. Here we report a study of the dielectric Breakdown in the narrow gap Mott insulators GaTa$_4$Se$_{8-x}$Te$_x$. We find that the I-V characteristics and the magnitude of the threshold electric field (E$_{th}$) do not correspond to a Zener Breakdown, but rather to an avalanche Breakdown. E$_{th}$ increases as a power law of the Mott Hubbard gap (E$_g$), in surprising agreement with the universal law E$_{th}$ $\propto$E$_g$$^{2.5}$ reported for avalanche Breakdown in semiconductors. However, the delay time for the avalanche that we observe in Mott insulators is over three orders of magnitude longer than in conventional semiconductors. Our results suggest that the electric field induces local insulator-to-metal Mott transitions that create conductive domains which grow to form filamentary paths across the sample.
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Resistive switching induced by electronic avalanche Breakdown in GaTa4Se8−xTex narrow gap Mott Insulators
2013Co-Authors: V. Guiot, L. Cario, E. Janod, B. Corraze, Ta V. Phuoc, M. Rozenberg, P. Stoliar, T. Cren, D. RoditchevAbstract:Mott transitions induced by strong electric fields are receiving a growing interest. Recent theoretical proposals have focused on the Zener dielectric Breakdown in Mott insulators, however experimental studies are still too scarce to conclude about the mechanism. Here we report a study of the dielectric Breakdown in the narrow gap Mott insulators GaTa4Se8−xTex. We find that the I-V characteristics and the magnitude of the threshold electric field (Eth) do not correspond to a Zener Breakdown, but rather to an avalanche Breakdown. Eth increases as a power law of the Mott Hubbard gap (Eg), in surprising agreement with the universal law Eth ∝Eg 2.5 reported for avalanche Breakdown in semiconductors. However
Sikandar Aftab - One of the best experts on this subject based on the ideXlab platform.
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Temperature-Dependent and Gate-Tunable Rectification in a Black Phosphorus/WS2 van der Waals Heterojunction Diode
2018Co-Authors: Ghulam Dastgeer, Sikandar Aftab, Kyung-ah Min, Ghazanfar Nazir, Amir Muhammad Afzal, Muhammad Farooq Khan, Bilal Abbas Naqvi, Janghwan Cha, Yasir Jamil, Jongwan JungAbstract:Heterostructures comprising two-dimensional (2D) semiconductors fabricated by individual stacking exhibit interesting characteristics owing to their 2D nature and atomically sharp interface. As an emerging 2D material, black phosphorus (BP) nanosheets have drawn much attention because of their small band gap semiconductor characteristics along with high mobility. Stacking structures composed of p-type BP and n-type transition metal dichalcogenides can produce an atomically sharp interface with van der Waals interaction which leads to p–n diode functionality. In this study, for the first time, we fabricated a heterojunction p–n diode composed of BP and WS2. The rectification effects are examined for monolayer, bilayer, trilayer, and multilayer WS2 flakes in our BP/WS2 van der Waals heterojunction diodes and also verified by density function theory calculations. We report superior functionalities as compared to other van der Waals heterojunction, such as efficient gate-dependent static rectification of 2.6 × 104, temperature dependence, thickness dependence of rectification, and ideality factor of the device. The temperature dependence of Zener Breakdown voltage and avalanche Breakdown voltage were analyzed in the same device. Additionally, superior optoelectronic characteristics such as photoresponsivity of 500 mA/W and external quantum efficiency of 103% are achieved in the BP/WS2 van der Waals p–n diode, which is unprecedented for BP/transition metal dichalcogenides heterostructures. The BP/WS2 van der Waals p–n diodes have a profound potential to fabricate rectifiers, solar cells, and photovoltaic diodes in 2D semiconductor electronics and optoelectronics
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Van der Waals heterojunction diode composed of WS2 flake placed on p-type Si substrate.
Nanotechnology, 2017Co-Authors: Sikandar Aftab, M. Farooq Khan, Kyung-ah Min, Ghazanfar Nazir, Amir Muhammad Afzal, Ghulam Dastgeer, Imtisal Akhtar, Yongho Seo, Suklyun Hong, Jonghwa EomAbstract:P–N junctions represent the fundamental building blocks of most semiconductors for optoelectronic functions. This work demonstrates a technique for forming a WS2/Si van der Waals junction based on mechanical exfoliation. Multilayered WS2 nanoflakes were exfoliated on the surface of bulk p-type Si substrates using a polydimethylsiloxane stamp. We found that the fabricated WS2/Si p–n junctions exhibited rectifying characteristics. We studied the effect of annealing processes on the performance of the WS2/Si van der Waals p–n junction and demonstrated that annealing improved its electrical characteristics. However, devices with vacuum annealing have an enhanced forward-bias current compared to those annealed in a gaseous environment. We also studied the top-gate-tunable rectification characteristics across the p–n junction interface in experiments as well as density functional theory calculations. Under various temperatures, Zener Breakdown occurred at low reverse-bias voltages, and its Breakdown voltage exhibited a negative coefficient of temperature. Another Breakdown voltage was observed, which increased with temperature, suggesting a positive coefficient of temperature. Therefore, such a Breakdown can be assigned to avalanche Breakdown. This work demonstrates a promising application of two-dimensional materials placed directly on conventional bulk Si substrates.
Jonghwa Eom - One of the best experts on this subject based on the ideXlab platform.
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Van der Waals heterojunction diode composed of WS2 flake placed on p-type Si substrate.
Nanotechnology, 2017Co-Authors: Sikandar Aftab, M. Farooq Khan, Kyung-ah Min, Ghazanfar Nazir, Amir Muhammad Afzal, Ghulam Dastgeer, Imtisal Akhtar, Yongho Seo, Suklyun Hong, Jonghwa EomAbstract:P–N junctions represent the fundamental building blocks of most semiconductors for optoelectronic functions. This work demonstrates a technique for forming a WS2/Si van der Waals junction based on mechanical exfoliation. Multilayered WS2 nanoflakes were exfoliated on the surface of bulk p-type Si substrates using a polydimethylsiloxane stamp. We found that the fabricated WS2/Si p–n junctions exhibited rectifying characteristics. We studied the effect of annealing processes on the performance of the WS2/Si van der Waals p–n junction and demonstrated that annealing improved its electrical characteristics. However, devices with vacuum annealing have an enhanced forward-bias current compared to those annealed in a gaseous environment. We also studied the top-gate-tunable rectification characteristics across the p–n junction interface in experiments as well as density functional theory calculations. Under various temperatures, Zener Breakdown occurred at low reverse-bias voltages, and its Breakdown voltage exhibited a negative coefficient of temperature. Another Breakdown voltage was observed, which increased with temperature, suggesting a positive coefficient of temperature. Therefore, such a Breakdown can be assigned to avalanche Breakdown. This work demonstrates a promising application of two-dimensional materials placed directly on conventional bulk Si substrates.
Yong Liu - One of the best experts on this subject based on the ideXlab platform.
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Zener Tunneling and Photoresponse of a WS2/Si van der Waals Heterojunction.
ACS applied materials & interfaces, 2016Co-Authors: Changyong Lan, Shuai Wang, Tianpeng Jiao, Dapeng Wei, Wenkui Jing, Yong LiuAbstract:Van der Waals heterostructures built from two-dimensional materials on a conventional semiconductor offer novel electronic and optoelectronic properties for next-generation information devices. Here we report that by simply stacking a vapor-phase-synthesized multilayer n-type WS2 film onto a p-type Si substrate, a high-responsivity Zener photodiode can be achieved. We find that above a small reverse threshold voltage of 0.5 V, the fabricated heterojunction exhibits Zener tunneling behavior which was confirmed by its negative temperature coefficient of the Breakdown voltage. The WS2/Si heterojunction working in the Zener Breakdown regime shows a stable and linear photoresponse, a broadband photoresponse ranging from 340 to 1100 nm with a maximum photoresponsivity of 5.7 A/W at 660 nm and a fast response speed of 670 μs. Such high performance can be attributed to the ultrathin depletion layer involved in the WS2/Si p–n junction, on which a strong electric field can be created even with a small reverse volta...
V. Guiot - One of the best experts on this subject based on the ideXlab platform.
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Avalanche Breakdown in GaTa_4Se_8−xTe_x narrow-gap Mott insulators
Nature Communications, 2013Co-Authors: V. Guiot, L. Cario, E. Janod, B. Corraze, M. Rozenberg, P. Stoliar, T. Cren, Vinh Ta Phuoc, D. RoditchevAbstract:Mott transitions induced by strong electric fields are receiving growing interest. Recent theoretical proposals have focused on the Zener dielectric Breakdown in Mott insulators. However, experimental studies are still too scarce to conclude about the mechanism. Here we report a study of the dielectric Breakdown in the narrow-gap Mott insulators GaTa_4Se_8− x Te_ x . We find that the I–V characteristics and the magnitude of the threshold electric field ( E _th) do not correspond to a Zener Breakdown, but rather to an avalanche Breakdown. E _th increases as a power law of the Mott–Hubbard gap ( E _g), in surprising agreement with the universal law E _th E _g^2.5 reported for avalanche Breakdown in semiconductors. However, the delay time for the avalanche that we observe in Mott insulators is over three orders of magnitude greater than in conventional semiconductors. Our results suggest that the electric field induces local insulator-to-metal Mott transitions that create conductive domains that grow to form filamentary paths across the sample. Dielectric Breakdown in Mott insulators induced by strong electric fields is thought to take place via a Zener mechanism. Guiot et al . show that the Breakdown characteristics are instead similar to the avalanche Breakdown in conventional semiconductors, although with much longer delay times.
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Resistive switching induced by electronic avalanche Breakdown in GaTa$_4$Se$_{8-x}$Te$_x$ narrow gap Mott Insulators
Nature Communications, 2013Co-Authors: V. Guiot, L. Cario, E. Janod, B. Corraze, M. Rozenberg, P. Stoliar, T. Cren, Vinh Ta Phuoc, D. RoditchevAbstract:Mott transitions induced by strong electric fields are receiving a growing interest. Recent theoretical proposals have focused on the Zener dielectric Breakdown in Mott insulators, however experimental studies are still too scarce to conclude about the mechanism. Here we report a study of the dielectric Breakdown in the narrow gap Mott insulators GaTa$_4$Se$_{8-x}$Te$_x$. We find that the I-V characteristics and the magnitude of the threshold electric field (E$_{th}$) do not correspond to a Zener Breakdown, but rather to an avalanche Breakdown. E$_{th}$ increases as a power law of the Mott Hubbard gap (E$_g$), in surprising agreement with the universal law E$_{th}$ $\propto$E$_g$$^{2.5}$ reported for avalanche Breakdown in semiconductors. However, the delay time for the avalanche that we observe in Mott insulators is over three orders of magnitude longer than in conventional semiconductors. Our results suggest that the electric field induces local insulator-to-metal Mott transitions that create conductive domains which grow to form filamentary paths across the sample.
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Resistive switching induced by electronic avalanche Breakdown in GaTa4Se8−xTex narrow gap Mott Insulators
2013Co-Authors: V. Guiot, L. Cario, E. Janod, B. Corraze, Ta V. Phuoc, M. Rozenberg, P. Stoliar, T. Cren, D. RoditchevAbstract:Mott transitions induced by strong electric fields are receiving a growing interest. Recent theoretical proposals have focused on the Zener dielectric Breakdown in Mott insulators, however experimental studies are still too scarce to conclude about the mechanism. Here we report a study of the dielectric Breakdown in the narrow gap Mott insulators GaTa4Se8−xTex. We find that the I-V characteristics and the magnitude of the threshold electric field (Eth) do not correspond to a Zener Breakdown, but rather to an avalanche Breakdown. Eth increases as a power law of the Mott Hubbard gap (Eg), in surprising agreement with the universal law Eth ∝Eg 2.5 reported for avalanche Breakdown in semiconductors. However
