In this study, atomic force microscope (AFM) tips are used as tools to cut and manipulate carbon nanotubes on various surfaces. The lateral forces acting on AFM tips during manipulation are also recorded and analyzed ...In this study, atomic force microscope (AFM) tips are used as tools to cut and manipulate carbon nanotubes on various surfaces. The lateral forces acting on AFM tips during manipulation are also recorded and analyzed from the perspective of micro-mechanics. It is found that differences in surface conditions can lead to obvious increase in micro-friction between nanotube and substrate. And also due to rehybridization, carbon nanotubes present excellent resilience when undergoing different degrees of strain. Finally, carbon nanotubes can complexly deform from elastic stage to plastic stage before complete rupture.展开更多
A scanning electron microscope(SEM)provides real-time imaging with nanometer resolution and a large scanning area,which enables the development and integration of robotic nanomanipulation systems inside a vacuum chamb...A scanning electron microscope(SEM)provides real-time imaging with nanometer resolution and a large scanning area,which enables the development and integration of robotic nanomanipulation systems inside a vacuum chamber to realize simultaneous imaging and direct interactions with nanoscaled samples.Emerging techniques for nanorobotic manipulation during SEM imaging enable the characterization of nanomaterials and nanostructures and the prototyping/assembly of nanodevices.This paper presents a comprehensive survey of recent advances in nanorobotic manipulation,including the development of nanomanipulation platforms,tools,changeable toolboxes,sensing units,control strategies,electron beam-induced deposition approaches,automation techniques,and nanomanipulation-enabled applications and discoveries.The limitations of the existing technologies and prospects for new technologies are also discussed.展开更多
Nanomanipulation plays an important role in nanofabrication, it is also a technology necessary in exploring the secrets of nanoworld, and it thus becomes a start point to research future nanomachine. In this study, ma...Nanomanipulation plays an important role in nanofabrication, it is also a technology necessary in exploring the secrets of nanoworld, and it thus becomes a start point to research future nanomachine. In this study, manipulation and cutting of carbon nanotubes have been conducted in order to examine whether we can move a nano-component from one site to another by using the tip of atomic force microscope (AFM). The technique may also be valuable for providing the constructive materials of nanofabrication. While exploring the method for manipulating and cutting of nanotubes, some new phenomena have been observed during the process. Results show that carbon nanotubes present a feature of deformation combining bending and distortion when subjected to large mechanical forces exerted by the tip of AFM. In special cases, long carbon nanotubes can be cut into two parts, by which we can remove the part where crystal lattice is flawed, and therefore a perfect nanocomponent can be obtained.展开更多
The orientation and shifting of individual carbon nanotubes are extremely important in the assembly of building blocks of nanodevices and in the development of one-dimensional materials for interdisciplinary applicati...The orientation and shifting of individual carbon nanotubes are extremely important in the assembly of building blocks of nanodevices and in the development of one-dimensional materials for interdisciplinary applications.Here,we report an optical method that is capable of producing the controlled orientation and targeted shifting of single multiwalled carbon nanotubes(MWCNTs)using an optical-fiber nanotip.In a demonstration of this technique,a single MWCNT with an outer diameter of 50 nm and a length of 0.9 mm was first trapped by the nanotip using a laser beam with a wavelength of 980 nm and was then oriented and shifted along the nanotip axis as a result of the interaction of the MWCNT with the optical field output by the nanotip.Various optical powers were applied to characterize the orientation and shifting performance.The orientation and shifting of MWCNTs of various sizes were also demonstrated.展开更多
Nanomanipulation of DNA molecules or other biomolecules to form artificial patterns or structures at nanometer scale has potential applications in the construction of molecular devices in future industries. It may als...Nanomanipulation of DNA molecules or other biomolecules to form artificial patterns or structures at nanometer scale has potential applications in the construction of molecular devices in future industries. It may also lead to new insights into the interesting properties and behavior of this fantastic nature-selected molecule at the sin- gle-molecular level. Here we present a special method based on the combination of macroscopic “molecular comb- ing” and microscopic “molecular cutting” to manipulate DNA molecules and form complex patterns at nanometer scale on solid surfaces. A possible strategy for ordered DNA sequencing based on this nanomanipulation technique has also been proposed.展开更多
尽管基于原子力显微镜(Atom force microscopy,AFM)的纳米操作在过去10年间取得了极大进展,但依然有两个问题没有得到很好解决:探针的精确定位和稳定性操作。由于压电陶瓷驱动器非线性和温漂的影响,使得探针相对于被操作物体的定位极其...尽管基于原子力显微镜(Atom force microscopy,AFM)的纳米操作在过去10年间取得了极大进展,但依然有两个问题没有得到很好解决:探针的精确定位和稳定性操作。由于压电陶瓷驱动器非线性和温漂的影响,使得探针相对于被操作物体的定位极其困难,从而造成纳米操作任务失败;同时,因为探针仅能对被操作物体施加点式作用力,在操作中经常出现探针滑过被操作物体,或者引起被操作物体的转动、形变等非理想结果,阻碍纳米操作的深入发展。针对上述问题,提出基于概率的虚拟夹具纳米操作方法,其核心思想是在基于路标观测的探针定位基础上,实现基于概率的探针多点并发操作策略—虚拟夹具方法。仿真与试验结果验证该方法可以稳定、长距离的推动纳米颗粒,能够对一维纳米材料(管、线、棒)进行定姿态操作,从而使AFM纳米操作效率得到极大提升。展开更多
To understand capillary interactions between probe tips and nanoparticles under ambient conditions, a theoretical model of capillary forces between them is developed based on the geometric relations. It is found that ...To understand capillary interactions between probe tips and nanoparticles under ambient conditions, a theoretical model of capillary forces between them is developed based on the geometric relations. It is found that the contribution of surface tension force to the total capillary force attains to similar order of magnitude as the capillary pressure force in many cases. It is also shown that the tip shape and the radial distance of the meniscus have great influence on the capillary force. The capillary force decreases with the increasing separation distances, and the variance of the contact angles may change the magnitudes of capillary forces several times at large radial distances. The applicability of the symmetric meniscus approximation is discussed.展开更多
Nanomanipulation under scanning electron microscopy(SEM)enables direct interactions of a tool with a sample.We recently developed a nanomanipulation technique for the extraction and identification of DNA contained wit...Nanomanipulation under scanning electron microscopy(SEM)enables direct interactions of a tool with a sample.We recently developed a nanomanipulation technique for the extraction and identification of DNA contained within sub-nuclear locations of a single cell nucleus.In nanomanipulation of sub-cellular structures,a key step is to identify targets of interest through correlating fluorescence and SEM images.The DNA extraction task must be conducted with low accelerating voltages resulting in low imaging resolutions.This is imposed by the necessity of preserving the biochemical integrity of the sample.Such poor imaging conditions make the identification of nanometer-sized fiducial marks difficult.This paper presents an affine scale-invariant feature transform(ASIFT)based method for correlating SEM images and fluorescence microscopy images.The performance of the image correlation approach under different noise levels and imaging magnifications was quantitatively evaluated.The optimal mean absolute error(MAE)of correlation results is 68634 nm under standard conditions.Compared with manual correlation by skilled operators,the automated correlation approach demonstrates a speed that is higher by an order of magnitude.With the SEM-fluorescence image correlation approach,targeted DNA was successfully extracted via nanomanipulation under SEM conditions.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.50135040 and 50173001).
文摘In this study, atomic force microscope (AFM) tips are used as tools to cut and manipulate carbon nanotubes on various surfaces. The lateral forces acting on AFM tips during manipulation are also recorded and analyzed from the perspective of micro-mechanics. It is found that differences in surface conditions can lead to obvious increase in micro-friction between nanotube and substrate. And also due to rehybridization, carbon nanotubes present excellent resilience when undergoing different degrees of strain. Finally, carbon nanotubes can complexly deform from elastic stage to plastic stage before complete rupture.
基金This study was supported by the Natural Sciences and Engineering Research Council of Canada,the Canada Research Chairs Program,and the Ontario Ministry of Research and Innovation via an ORF-RE grant.
文摘A scanning electron microscope(SEM)provides real-time imaging with nanometer resolution and a large scanning area,which enables the development and integration of robotic nanomanipulation systems inside a vacuum chamber to realize simultaneous imaging and direct interactions with nanoscaled samples.Emerging techniques for nanorobotic manipulation during SEM imaging enable the characterization of nanomaterials and nanostructures and the prototyping/assembly of nanodevices.This paper presents a comprehensive survey of recent advances in nanorobotic manipulation,including the development of nanomanipulation platforms,tools,changeable toolboxes,sensing units,control strategies,electron beam-induced deposition approaches,automation techniques,and nanomanipulation-enabled applications and discoveries.The limitations of the existing technologies and prospects for new technologies are also discussed.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 50075043, 50135040 and 50173001)the Doctorate Designation Fund of the Ministry of Education of China (Grant No. 2000000339).
文摘Nanomanipulation plays an important role in nanofabrication, it is also a technology necessary in exploring the secrets of nanoworld, and it thus becomes a start point to research future nanomachine. In this study, manipulation and cutting of carbon nanotubes have been conducted in order to examine whether we can move a nano-component from one site to another by using the tip of atomic force microscope (AFM). The technique may also be valuable for providing the constructive materials of nanofabrication. While exploring the method for manipulating and cutting of nanotubes, some new phenomena have been observed during the process. Results show that carbon nanotubes present a feature of deformation combining bending and distortion when subjected to large mechanical forces exerted by the tip of AFM. In special cases, long carbon nanotubes can be cut into two parts, by which we can remove the part where crystal lattice is flawed, and therefore a perfect nanocomponent can be obtained.
基金This work was supported by the National Natural Science Foundation of China(Nos.11274395 and 61205165)the Program for Changjiang Scholars and Innovative Research Team in University(IRT13042)
文摘The orientation and shifting of individual carbon nanotubes are extremely important in the assembly of building blocks of nanodevices and in the development of one-dimensional materials for interdisciplinary applications.Here,we report an optical method that is capable of producing the controlled orientation and targeted shifting of single multiwalled carbon nanotubes(MWCNTs)using an optical-fiber nanotip.In a demonstration of this technique,a single MWCNT with an outer diameter of 50 nm and a length of 0.9 mm was first trapped by the nanotip using a laser beam with a wavelength of 980 nm and was then oriented and shifted along the nanotip axis as a result of the interaction of the MWCNT with the optical field output by the nanotip.Various optical powers were applied to characterize the orientation and shifting performance.The orientation and shifting of MWCNTs of various sizes were also demonstrated.
基金Supported by National Natural Science Foundation of China (NSFC) under grant No.10335070. Financial support from the Chinese Academy of Sciences and Shanghai Scientific and Technological Committee is also appreciated.
文摘Nanomanipulation of DNA molecules or other biomolecules to form artificial patterns or structures at nanometer scale has potential applications in the construction of molecular devices in future industries. It may also lead to new insights into the interesting properties and behavior of this fantastic nature-selected molecule at the sin- gle-molecular level. Here we present a special method based on the combination of macroscopic “molecular comb- ing” and microscopic “molecular cutting” to manipulate DNA molecules and form complex patterns at nanometer scale on solid surfaces. A possible strategy for ordered DNA sequencing based on this nanomanipulation technique has also been proposed.
文摘尽管基于原子力显微镜(Atom force microscopy,AFM)的纳米操作在过去10年间取得了极大进展,但依然有两个问题没有得到很好解决:探针的精确定位和稳定性操作。由于压电陶瓷驱动器非线性和温漂的影响,使得探针相对于被操作物体的定位极其困难,从而造成纳米操作任务失败;同时,因为探针仅能对被操作物体施加点式作用力,在操作中经常出现探针滑过被操作物体,或者引起被操作物体的转动、形变等非理想结果,阻碍纳米操作的深入发展。针对上述问题,提出基于概率的虚拟夹具纳米操作方法,其核心思想是在基于路标观测的探针定位基础上,实现基于概率的探针多点并发操作策略—虚拟夹具方法。仿真与试验结果验证该方法可以稳定、长距离的推动纳米颗粒,能够对一维纳米材料(管、线、棒)进行定姿态操作,从而使AFM纳米操作效率得到极大提升。
文摘To understand capillary interactions between probe tips and nanoparticles under ambient conditions, a theoretical model of capillary forces between them is developed based on the geometric relations. It is found that the contribution of surface tension force to the total capillary force attains to similar order of magnitude as the capillary pressure force in many cases. It is also shown that the tip shape and the radial distance of the meniscus have great influence on the capillary force. The capillary force decreases with the increasing separation distances, and the variance of the contact angles may change the magnitudes of capillary forces several times at large radial distances. The applicability of the symmetric meniscus approximation is discussed.
基金This work was supported by Canadian Institutes of Health Research via a Catalyst Grant,the Canada Research Chairs Program,the Ontario Research Funds--Research Excellence Program and the Natural Sciences and Engineering Research Council of Canada via a Strategic Projects Grant.
文摘Nanomanipulation under scanning electron microscopy(SEM)enables direct interactions of a tool with a sample.We recently developed a nanomanipulation technique for the extraction and identification of DNA contained within sub-nuclear locations of a single cell nucleus.In nanomanipulation of sub-cellular structures,a key step is to identify targets of interest through correlating fluorescence and SEM images.The DNA extraction task must be conducted with low accelerating voltages resulting in low imaging resolutions.This is imposed by the necessity of preserving the biochemical integrity of the sample.Such poor imaging conditions make the identification of nanometer-sized fiducial marks difficult.This paper presents an affine scale-invariant feature transform(ASIFT)based method for correlating SEM images and fluorescence microscopy images.The performance of the image correlation approach under different noise levels and imaging magnifications was quantitatively evaluated.The optimal mean absolute error(MAE)of correlation results is 68634 nm under standard conditions.Compared with manual correlation by skilled operators,the automated correlation approach demonstrates a speed that is higher by an order of magnitude.With the SEM-fluorescence image correlation approach,targeted DNA was successfully extracted via nanomanipulation under SEM conditions.
基金financially supported by the German Research Foundation(509134333)the Australian Research Council(DP220103222)the National Natural Science Foundation of China(11674399)。
