Based on the non-equilibrium Green＇s method and density functional theory, the magnetic transport of Fe- phthMocyanine dimers with two armchair single-wailed carbon nanotube electrodes is investigated. The results sh...Based on the non-equilibrium Green＇s method and density functional theory, the magnetic transport of Fe- phthMocyanine dimers with two armchair single-wailed carbon nanotube electrodes is investigated. The results show that the system can present high-performance spin filtering, magnetoresistance, and low-bias spin negative differential resistance effects by tuning the external magnetic field. These results show that the Fe-phthalocyanine dimer has the potential to design future molecular spintronic devices.展开更多
Carbon source precursor is a critical factor governing chemical vapor deposition growth of graphene films.Methane(CH4),has been the most commonly used precursor in the last decade,but it presents challenges in terms o...Carbon source precursor is a critical factor governing chemical vapor deposition growth of graphene films.Methane(CH4),has been the most commonly used precursor in the last decade,but it presents challenges in terms of decomposition efficiency and growth rate.Here we thoroughly evaluated acetylene(C2H_(2)),a precursor that is probably for providing carbon dimer(C2)species,for fast growth of large-scale graphene films.We find that the graphene growth behaviors fueled by C2H_(2) exhibit unconventional localized growth behavior with significant advantages in terms of high growth rate,which mainly ascribe to the as-decomposed C2 species.Therefore,a C2-fueled scanning growth strategy is proposed,and the fast scanning growth rate of 40 cm/min was experimentally demonstrated.This growth strategy is compatible with the approach of unidirectional growth of single-crystal graphene films,and the as-grown graphene films are of high-quality.This work demonstrates a reliable and promising strategy for the rapid synthesis of high-quality graphene film and may pave the avenue to cost-effective mass production of graphene materials in the roll-to-roll system.展开更多
Making the propagation of sound waves immune to interference from obstacles with high transmission efficiency is a long-term pursuit in acoustic science and engineering.Recent proposal pointed out that perfect transmi...Making the propagation of sound waves immune to interference from obstacles with high transmission efficiency is a long-term pursuit in acoustic science and engineering.Recent proposal pointed out that perfect transmission through obstacles can be achieved by deploying a bulky gain-loss distribution in parity-time(PT)symmetry.Here we demonstrate a modified methodology to achieve the extraordinary physical property of acoustic cloaking accompanied by perfect transmission at the exceptional points(EPs).Systematically probing reveals two complementary solutions of EPs corresponding to acoustic cloaking,in the system composed of an equivalent medium slab sandwiched by a pair of PT-symmetric admittance metasurfaces.To model the crucial acoustic gains that are not present in nature,we employ actively controlled ultra-thin carbon nanotube dimer films to mimic admittance metasurfaces perfectly via thermoacoustic effect,and manipulate acoustic cloaking over a wide frequency band in experiments.This divergent strategy releases restrictions on the operating frequency,shape and size of the obstacle,which can be applied to acoustic sensing,directional imaging,and other related wave disciplines.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 11104115the Natural Science Foundation of Shandong Province under Grant No ZR2016AM11
文摘Based on the non-equilibrium Green＇s method and density functional theory, the magnetic transport of Fe- phthMocyanine dimers with two armchair single-wailed carbon nanotube electrodes is investigated. The results show that the system can present high-performance spin filtering, magnetoresistance, and low-bias spin negative differential resistance effects by tuning the external magnetic field. These results show that the Fe-phthalocyanine dimer has the potential to design future molecular spintronic devices.
基金the National Natural Science Foundation of China(No.T2188101)the Beijing National Laboratory for Molecular Science(No.BNLMS-CXTD-202001).
文摘Carbon source precursor is a critical factor governing chemical vapor deposition growth of graphene films.Methane(CH4),has been the most commonly used precursor in the last decade,but it presents challenges in terms of decomposition efficiency and growth rate.Here we thoroughly evaluated acetylene(C2H_(2)),a precursor that is probably for providing carbon dimer(C2)species,for fast growth of large-scale graphene films.We find that the graphene growth behaviors fueled by C2H_(2) exhibit unconventional localized growth behavior with significant advantages in terms of high growth rate,which mainly ascribe to the as-decomposed C2 species.Therefore,a C2-fueled scanning growth strategy is proposed,and the fast scanning growth rate of 40 cm/min was experimentally demonstrated.This growth strategy is compatible with the approach of unidirectional growth of single-crystal graphene films,and the as-grown graphene films are of high-quality.This work demonstrates a reliable and promising strategy for the rapid synthesis of high-quality graphene film and may pave the avenue to cost-effective mass production of graphene materials in the roll-to-roll system.
基金The project was supported by National Natural Science Foundation of China(21573201)the Ministry of Science and Technology of China(2016YFA0200604)and the Special Program for Applied Research on Super Computation of the National Nature Science Foundation of China-Guangdong Joint Fund(U1501501)~~
基金supported by the National Key Research and Development Program of China(Grant No.2022YFA1404400)the National Natural Science Foundation of China(Grant Nos.11834008,11904035,12074183,12225408,and 12227809)+2 种基金the Qing Lan Project of Jiangsu Provincethe Natural Science Foundation of the Jiangsu Higher Education Institutions of China(Grant No.23KJD140001)Changzhou Sci&Tech Program(Grant No.CJ20220256)。
文摘Making the propagation of sound waves immune to interference from obstacles with high transmission efficiency is a long-term pursuit in acoustic science and engineering.Recent proposal pointed out that perfect transmission through obstacles can be achieved by deploying a bulky gain-loss distribution in parity-time(PT)symmetry.Here we demonstrate a modified methodology to achieve the extraordinary physical property of acoustic cloaking accompanied by perfect transmission at the exceptional points(EPs).Systematically probing reveals two complementary solutions of EPs corresponding to acoustic cloaking,in the system composed of an equivalent medium slab sandwiched by a pair of PT-symmetric admittance metasurfaces.To model the crucial acoustic gains that are not present in nature,we employ actively controlled ultra-thin carbon nanotube dimer films to mimic admittance metasurfaces perfectly via thermoacoustic effect,and manipulate acoustic cloaking over a wide frequency band in experiments.This divergent strategy releases restrictions on the operating frequency,shape and size of the obstacle,which can be applied to acoustic sensing,directional imaging,and other related wave disciplines.
