The activity and stability of Cu nanostructures strongly depend on their sizes,morphology and structures.Here we report the preparation of two-dimensional(2 D)Cu@Cu-BTC core-shell nanosheets(NSs).The thickness of the ...The activity and stability of Cu nanostructures strongly depend on their sizes,morphology and structures.Here we report the preparation of two-dimensional(2 D)Cu@Cu-BTC core-shell nanosheets(NSs).The thickness of the Cu NSs could be tuned to sub-10 nm through a mild etching process,in which the Cu-BTC in situ grow along with the oxidation on the surface of the Cu NSs.This unique strategy can also be extended to synthesize one-dimensional(1 D)Cu@Cu-BTC nanowires(NWs).Furthermore,the obtained Cu@Cu-BTC NSs could be applied as an effective material to the memory device with the write-onceread-many times(WORM)behavior and the high ION/I(OFF)ratio(>2.7×103).展开更多
Since the work of Penrose and Hameroff the possibility is discussed that the location of human memory and consciousness could be connected with tubulin microtubules. If one would use superionic nano-materials rolled u...Since the work of Penrose and Hameroff the possibility is discussed that the location of human memory and consciousness could be connected with tubulin microtubules. If one would use superionic nano-materials rolled up to microtubules with an electrolyte inside the formed channels mediating fast ionic exchange of protons respectively lithium ions, it seems to be possible to write into such materials whole image arrays (pictures) under the action of the complex electromagnetic spectrum that composes these images. The same material and architecture may be recommended for super-computers. Especially microtubules with a protofilament number of 13 are the most important to note. We connected such microtubules before with Fibonacci nets composed of 13 sub-cells that were helically rolled up to deliver suitable channels. Our recent Fibonacci analysis of Wadsley-Roth shear phases such as niobium tungsten oxide , exhibiting channels for ultra-fast lithium-ion diffusion, suggests to use these materials, besides super-battery main application, in form of nanorods or microtubules as effectively working superionic memory devices for computers that work ultra-fast with the complex effectiveness of human brains. Finally, we pose the question, whether dark matter, ever connected with ultrafast movement of ordinary matter, may be responsible for synchronization between interactions of human brains and consciousness.展开更多
We propose a nonvolatile resistive random access memory device by employing nanodispersion of zirconia(ZrO2) quantum dots(QDs) for the formation of an active layer. The memory devices comprising a typical sandwich str...We propose a nonvolatile resistive random access memory device by employing nanodispersion of zirconia(ZrO2) quantum dots(QDs) for the formation of an active layer. The memory devices comprising a typical sandwich structure of Ag(top)/ZrO2(active layer)/Ti(bottom) are fabricated using a facile spin-coating method. The optimized device exhibits a high resistance state/low resistance state resistance difference(about 10 Ω), a good cycle performance(the number of cycles larger than 100), and a relatively low conversion current(about 1 μA). Atomic force microscopy and scanning electron microscope are used to observe the surface morphology and stacking state of the ZrO2 active layer. Experimental results show that the ZrO2 active layer is stacked compactly and has a low roughness(Ra=4.49 nm) due to the uniform distribution of the ZrO2 QDs. The conductive mechanism of the Ag/ZrO2/Ti device is analyzed and studied, and the conductive filaments of Ag ions and oxygen vacancies are focused on to clarify the resistive switching memory behavior. This study offers a facile approach of memristors for future electronic applications.展开更多
Heavy-ion flux is an important experimental parameter in the ground based single event tests. The flux impact on a single event effect in different memory devices is analyzed by using GEANT4 and TCAD simulation method...Heavy-ion flux is an important experimental parameter in the ground based single event tests. The flux impact on a single event effect in different memory devices is analyzed by using GEANT4 and TCAD simulation methods. The transient radial track profile depends not only on the linear energy transfer （LET） of the incident ion, but also on the mass and energy of the ion. For the ions with the energies at the Bragg peaks, the radial charge distribution is wider when the ion LET is larger. The results extracted from the GEANT4 and TCAD simulations, together with detailed analysis of the device structure, are presented to demonstrate phenomena observed in the flux related experiment. The analysis shows that the flux effect conclusions drawn from the experiment are intrinsically connected and all indicate the mechanism that the flux effect stems from multiple ion-induced pulses functioning together and relies exquisitely on the specific response of the device.展开更多
A three-terminal device based on electronic phase separated manganites is suggested to produce high performance resistive switching. Our Monte Carlo simulations reveal that the conductive filaments can be formed/annih...A three-terminal device based on electronic phase separated manganites is suggested to produce high performance resistive switching. Our Monte Carlo simulations reveal that the conductive filaments can be formed/annihilated by reshaping the ferromagnetic metal phase domains with two cross-oriented switching voltages. Besides, by controlling the high resistance state（HRS） to a stable state that just after the filament is ruptured, the resistive switching remains stable and reversible, while the switching voltage and the switching time can be greatly reduced.展开更多
A composition-modulated （HfO2）x（Al2O3）1-x charge trapping layer is proposed for charge trap flash memory by controlling the A1 atom content to form a peak and valley shaped band gap. It is found that the memory de...A composition-modulated （HfO2）x（Al2O3）1-x charge trapping layer is proposed for charge trap flash memory by controlling the A1 atom content to form a peak and valley shaped band gap. It is found that the memory device using the composition-modulated （HfO2）x（Al2O3）l-x as the charge trapping layer exhibits a larger memory window of 11.5 V, improves data retention even at high temperature, and enhances the program/erase speed. Improvements of the memory characteristics are attributed to the special band-gap structure resulting from the composition-modulated trapping layer. Therefore, the composition-modulated charge trapping layer may be useful in future nonvolatile flash memory device application.展开更多
A simulation approach is developed to obtain the linear energy transfer(LET) spectrum of all secondary ions and predict single event upset(SEU) occurrence induced by neutron in memory devices. Neutron reaction channel...A simulation approach is developed to obtain the linear energy transfer(LET) spectrum of all secondary ions and predict single event upset(SEU) occurrence induced by neutron in memory devices. Neutron reaction channels, secondary ion species and energy ranges, and LET calculation method are introduced respectively. Experimental results of neutron induced SEU effects on static random access memory(SRAM) and programmable read only memory(EEPROM) are presented to confirm the validity of the simulation results.展开更多
基金supported by the National Key R&D Program of China(No.2017YFA0700104)National Natural Science Foundation of China(Nos.21571169,21871238)+2 种基金Fundamental Research Funds for the Central Universities(No.WK2060190081)Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2018494)Young Elite Scientists Sponsorship Program by CAST(No.2016QNRC001)
文摘The activity and stability of Cu nanostructures strongly depend on their sizes,morphology and structures.Here we report the preparation of two-dimensional(2 D)Cu@Cu-BTC core-shell nanosheets(NSs).The thickness of the Cu NSs could be tuned to sub-10 nm through a mild etching process,in which the Cu-BTC in situ grow along with the oxidation on the surface of the Cu NSs.This unique strategy can also be extended to synthesize one-dimensional(1 D)Cu@Cu-BTC nanowires(NWs).Furthermore,the obtained Cu@Cu-BTC NSs could be applied as an effective material to the memory device with the write-onceread-many times(WORM)behavior and the high ION/I(OFF)ratio(>2.7×103).
文摘Since the work of Penrose and Hameroff the possibility is discussed that the location of human memory and consciousness could be connected with tubulin microtubules. If one would use superionic nano-materials rolled up to microtubules with an electrolyte inside the formed channels mediating fast ionic exchange of protons respectively lithium ions, it seems to be possible to write into such materials whole image arrays (pictures) under the action of the complex electromagnetic spectrum that composes these images. The same material and architecture may be recommended for super-computers. Especially microtubules with a protofilament number of 13 are the most important to note. We connected such microtubules before with Fibonacci nets composed of 13 sub-cells that were helically rolled up to deliver suitable channels. Our recent Fibonacci analysis of Wadsley-Roth shear phases such as niobium tungsten oxide , exhibiting channels for ultra-fast lithium-ion diffusion, suggests to use these materials, besides super-battery main application, in form of nanorods or microtubules as effectively working superionic memory devices for computers that work ultra-fast with the complex effectiveness of human brains. Finally, we pose the question, whether dark matter, ever connected with ultrafast movement of ordinary matter, may be responsible for synchronization between interactions of human brains and consciousness.
基金the National Natural Science Foundation of China(No.21808009)the Beijing Natural Science Foundation,China(No.2182051)。
文摘We propose a nonvolatile resistive random access memory device by employing nanodispersion of zirconia(ZrO2) quantum dots(QDs) for the formation of an active layer. The memory devices comprising a typical sandwich structure of Ag(top)/ZrO2(active layer)/Ti(bottom) are fabricated using a facile spin-coating method. The optimized device exhibits a high resistance state/low resistance state resistance difference(about 10 Ω), a good cycle performance(the number of cycles larger than 100), and a relatively low conversion current(about 1 μA). Atomic force microscopy and scanning electron microscope are used to observe the surface morphology and stacking state of the ZrO2 active layer. Experimental results show that the ZrO2 active layer is stacked compactly and has a low roughness(Ra=4.49 nm) due to the uniform distribution of the ZrO2 QDs. The conductive mechanism of the Ag/ZrO2/Ti device is analyzed and studied, and the conductive filaments of Ag ions and oxygen vacancies are focused on to clarify the resistive switching memory behavior. This study offers a facile approach of memristors for future electronic applications.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.U1532261,11690041,and 11675233)
文摘Heavy-ion flux is an important experimental parameter in the ground based single event tests. The flux impact on a single event effect in different memory devices is analyzed by using GEANT4 and TCAD simulation methods. The transient radial track profile depends not only on the linear energy transfer （LET） of the incident ion, but also on the mass and energy of the ion. For the ions with the energies at the Bragg peaks, the radial charge distribution is wider when the ion LET is larger. The results extracted from the GEANT4 and TCAD simulations, together with detailed analysis of the device structure, are presented to demonstrate phenomena observed in the flux related experiment. The analysis shows that the flux effect conclusions drawn from the experiment are intrinsically connected and all indicate the mechanism that the flux effect stems from multiple ion-induced pulses functioning together and relies exquisitely on the specific response of the device.
基金supported by the National Basic Research Program of China(Grant No.2011CB922101)the National Natural Science Foundation of China(Grant Nos.51301084 and 11234005)+1 种基金the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20130576)Program for Changjiang Scholars and Innovative Research Team in University,China(Grant No.IRT1243)
文摘A three-terminal device based on electronic phase separated manganites is suggested to produce high performance resistive switching. Our Monte Carlo simulations reveal that the conductive filaments can be formed/annihilated by reshaping the ferromagnetic metal phase domains with two cross-oriented switching voltages. Besides, by controlling the high resistance state（HRS） to a stable state that just after the filament is ruptured, the resistive switching remains stable and reversible, while the switching voltage and the switching time can be greatly reduced.
基金supported by the Science and Technology Research Key Project of Education Department of Henan, China (Grant No. 13A140021)the National Natural Science Foundation of China (Grant Nos. 50972054 and 61176124)+1 种基金the National Basic Research Program of China (Grant No. 2010CB934201)the State Key Program for Science and Technology of China (Grant No. 2009ZX02039-004)
文摘A composition-modulated （HfO2）x（Al2O3）1-x charge trapping layer is proposed for charge trap flash memory by controlling the A1 atom content to form a peak and valley shaped band gap. It is found that the memory device using the composition-modulated （HfO2）x（Al2O3）l-x as the charge trapping layer exhibits a larger memory window of 11.5 V, improves data retention even at high temperature, and enhances the program/erase speed. Improvements of the memory characteristics are attributed to the special band-gap structure resulting from the composition-modulated trapping layer. Therefore, the composition-modulated charge trapping layer may be useful in future nonvolatile flash memory device application.
基金Supported by National Natural Science Foundation of China(No.11235008)
文摘A simulation approach is developed to obtain the linear energy transfer(LET) spectrum of all secondary ions and predict single event upset(SEU) occurrence induced by neutron in memory devices. Neutron reaction channels, secondary ion species and energy ranges, and LET calculation method are introduced respectively. Experimental results of neutron induced SEU effects on static random access memory(SRAM) and programmable read only memory(EEPROM) are presented to confirm the validity of the simulation results.
