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Joseph J.Thomson;1897年发现电子，1906年诺贝尔奖志同道合的合作伙伴照明系统照明系统成像系统成像系统电子光学信息传递系统电子光学信息传递系统物镜系统物镜系统信号处理系统信号处理系统K.Lu et al,Science,304(2004)422纳米技术引起的纳米技术引起的 照明技术革命（照明技术革命（LED）The width of the quantum well is 1.5 nm or three basal plane spacing.The horizontal separation corresponds to 0.276nm,the(1-100)spacing,which is close to the interatomic separation in GaN.Zhong Lin Wang et al,SCIENCE;303(2004),1348PseudoMackay Clusters(H.Klein,1998)Al-Pd-MnAl-Pd-Mn 准晶近似相中的独特位错结构准晶近似相中的独特位错结构准晶近似相中的独特位错结构准晶近似相中的独特位错结构 HREM image of the -AlPdMn phase seen along its b axis.复杂合金相所拥有的超大的复杂合金相所拥有的超大的晶胞常数，导致其中全位错的晶胞常数，导致其中全位错的Burgers矢量大于矢量大于10 。而如此。而如此大的大的Burgers矢量使得位错的弹矢量使得位错的弹性应变能变得非常大，甚至达到性应变能变得非常大，甚至达到了在传统晶体学中不可理解的的了在传统晶体学中不可理解的的程度。程度。一个香蕉形拼块和一个正五边形拼块组成一维相一个香蕉形拼块和一个正五边形拼块组成一维相缺陷缺陷 phason line，它的线性方向平行于，它的线性方向平行于 b轴。轴。Jumps related to the defect motion by one step.?在塑性形变中，结构的转变是通过在塑性形变中，结构的转变是通过phason lines的的产生和移动来得以实现的。而产生和移动来得以实现的。而phason lines的移动的移动是以原子相跳跃的方式，部分的破坏初始的是以原子相跳跃的方式，部分的破坏初始的cluster，并在新的位置重构。，并在新的位置重构。（2-3）d=1.83 Metadislocation:在在phason lines形成的周期格子中存在的一形成的周期格子中存在的一种结构缺陷。种结构缺陷。A dislocation in the lattice of phason lines where six halfplanes of phason lines are inserted on the left-hand side.Burgers vector of metadislocation:171 Diffraction patterns with the incident beam parallel to the b axisPossibilities may occur:They can form close loops;They can terminate with both ends at the surface;They can terminate at a dislocation.Ordered AlloysD Di is ss so oc ci ia at te ed d d do omma ai in n b bo ou un nd da ar ri ie es s i in n -A Al l-P Pd d-MMn n 复杂结构合金相复杂结构合金相复杂结构合金相复杂结构合金相-AlPdMn-AlPdMn中的畴结构缺陷中的畴结构缺陷中的畴结构缺陷中的畴结构缺陷(E.Ruedl)(S.Amelinckx)HREM images of Dissociated domain boundaries in the-Al-Pd-Mn phase viewed along the 010 zone axis,showing DBs with different width？Part of the DB region is outlined by white lines,in which saw-toothed polygons with different lengths and a characteristic phason line(as indicated with an arrowhead)are clearly seen.畴界这种二维面缺陷可以利用位移矢量来描述，畴界区域的结构可以通过完整畴界这种二维面缺陷可以利用位移矢量来描述，畴界区域的结构可以通过完整晶体的两部分沿着位移矢量移动来形成。晶体的两部分沿着位移矢量移动来形成。Demo of displacement of two parts in I layerlayer:R畴界区域缺陷的高分辨模拟畴界区域缺陷的高分辨模拟畴界区域缺陷的高分辨模拟畴界区域缺陷的高分辨模拟Simulated HREM images for the DB planar defects parallel to(0 0 1)and(0 1 1)planes,respectively.ca HREM images of DBs in the-Al-Pd-Mn phase viewed along the 010 zone axis.Part of the DB region is outlined by white lines,in which saw-toothed polygons with different lengths and characteristic phason lines are clearly seen.Fig.1.Calculated images of SrTiO3,demonstrating the improvement in image resolution.(A)Structure projected along the 011 crystal direction.(B)Image under Scherzer focus conditions in the uncorrected instrument;CS 1.23 mm,Z 68 nm.(C)Image for CS 40 um and Z 8 nm.(D)Image for the new imaging mode,adjusting for CS40 um and Z8 nm.The calculations here are arried out for a specimen 4 um thick.The attainment of real atomic resolution is demonstrated by calculations for(E)an empty oxygen column,(F)a 50%oxygen occupancy,and(G)a shift of the oxygen column by 0.05 nm.The effect on contrast is localized at the single atomic column(arrow).Jia et al.;SCIENCE 299(2003),870Fig.2.Experimental image of SrTiO3 011.The spherical aberration coefficient was adjusted for CS 40 um,and an overfocus of Z 8 nm was used.Atom columns in the 4-nm thick specimen appear bright on a dark background,and oxygen is atomically resolved.At positions 1 and 2 the oxygen-atom contrast is weaker than in the neighboring oxygen-atom positions.This is shown quantitatively by the intensity trace in inset(A).This trace was taken directly from the digital readout of the CCD camera.Inset(B)shows a calculated image,assuming a reduced oxygen occupancy of 85 and 80%,respectively,for the oxygen-atom columns 3 and 4.The corresponding intensity trace inset(C)is in good agreement with the experimental trace(A).Fig.3.Experimental images of YBa2Cu3O7 in different crystal orientations.(A)A 90 tilt boundary(black arrow)separates two crystal domains.In the upper part,the crystal orientation(along the viewing direction)is parallel to 100,whereas it is parallel to 001 in the lower part of the image.Comparison with the structure model(C)indicates that all atomic positions of the cations Ba,Y,and Cu and of the oxygen are imaged white on a dark background at atomic resolution.In the upper part of(A),clearly alternating copper and oxygen occupancy can be seen along the horizontal 010 Cu-O chains(red arrow).(B)The crystal is imaged along the 010 directioni.e.,tilted with respect to(A)by 90 around the vertical axis.The 010 Cu-O chains are now seen end-on.The potential oxygen positions in between the Cu-atom positions in the so-called Cu-Ochain planes(red arrow)are empty.This provides evidence of oxygen ordering in the Cu-Ochain planes.In(A)and(B)a“124”fault also occurs(marked by double arrowheads)seen along the 100 and 010 crystal directions,respectively.In(B),the enhanced bright contrast of the 010 Cu-O chains(seen end-on)in the fault plane indicates high oxygen occupancy and ordering there.纳米尺度结构、成分、电子结构的综合分析纳米尺度结构、成分、电子结构的综合分析分辨率分辨率对对t样品样品=10nmdADF=0.23nmdEELS=0.26nm和同步辐射分辨率相和同步辐射分辨率相当但具有纳米尺度空当但具有纳米尺度空间分辨的能谱技术间分辨的能谱技术应用应用：材料的尺寸和形状在材料的尺寸和形状在纳米尺度上的涨落对纳米尺度上的涨落对电子结构的影响；界电子结构的影响；界面电子结构的表征面电子结构的表征PRL v88 p247002(2002)预期结果预期结果电子全息图电子全息图I(X)(x)=FI(x)全息位相全息位相 分布分布 (x)=o 2V(x)/x2 V(x)=(x)/电势场分布电势场分布电荷类型与分布电荷类型与分布=e(Ee(EKEKE+m+mo oC C2 2)t/)t/h hCECEKEKE(E(EKEKE+2m+2mo oC C2 2)1/21/2t t是样品的厚度。是样品的厚度。功能薄膜界面势场的电子全息研究功能薄膜界面势场的电子全息研究SrTiO3 24o001倾转晶界界面倾转晶界界面1伏特伏特2纳米纳米掺掺MndF FM I FMAppl.Phys.Lett.70,3050(1997)Appl.Phys.Lett.78,2026(2000)Appl.Phys.Lett.78,3103(2000)Appl.Phys.Lett.78,3496(2000)J.Appl.Phys.87,6070(2000)J.Appl.Phys.88,429(2000)A few methods have been used to characterize the growth of ultra-thin oxide layers and revealed the importance of optimizing the plasma oxidation process and preventing oxidation of the underlying electrode，but no research has focused on the slight oxidation of top electrode,which is also important to the TMR.主要相关国际进展Ta capFM NiFe(6nm)AlOx(wedge)AFM FeMn(12nm)Ta bufferFM NiFe(6nm)Al层最佳氧化的隧道结截面样品的高分辨像。几对白色的平行线标注出了NiFe电极中不同晶粒中的111面。可以看到底电极一层一层的(111)织构匹配生长，而顶电极则是多晶取向的三维岛状生长。Eliminate the magnetostatic contributionInfluence can be neglected hologramPhase imageOptimum-oxidized barrier MTJThe top interface is actually less sharp than the bottom interface.The top electrode is slightly oxidized in optimum-oxidized MTJ.Filled State at-2V2 inch Si wafer100nm STM27nm STM全同纳米团簇阵列全同纳米团簇阵列J.F.Jia et al.,APL 80,3186(2002)J.L.Li et al.,PRL 88,066101(2002)幻数成簇幻数成簇+纳米模板纳米模板1.5nmInterfacial Engineering:Magic on Magic均匀纳米团簇和纳米点或颗粒有序阵列的生长均匀纳米团簇和纳米点或颗粒有序阵列的生长Co cluster-Magic height(2ML)Applied Field(Gauss)Magnetic Moment(10-6 emu)5 KCo QDsFeGdCr(001)AF CrKubetzka et al.,PRL 88,057201(2002)Soft and super-paramagnetic纳米磁性纳米磁性/电子的电子的自旋量子态自旋量子态探测探测电化学自旋阀探针电化学自旋阀探针I=I0(1+P)I=I0(1P)P=(II)/(I+I)自旋极化扫描隧道显微像自旋极化扫描隧道显微像自旋极化扫描隧道显微像自旋极化扫描隧道显微像/谱谱谱谱Science 288,1805(2000)Science 292,2053(2001)关键科学问题关键科学问题关键科学问题关键科学问题（2 2）Stipe,Rezaei,and Ho,PRL 82,1724(99)Acetylene/Cu(001)单分子非弹性隧道谱单分子非弹性隧道谱技技技技术术术术途途途途径径径径与与与与关关关关键键键键问问问问题题题题关键科学问题关键科学问题关键科学问题关键科学问题（3 3）原子结构原子结构+单分子识别单分子识别谢谢！谢谢！十次准晶的输运性能沿周期与准周期方向存在明显各向异性
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