High coherent solid-state qubit from a pair of quantum dots
耗散腔量子电动力学系统中量子Fisher信息和量子相干性分布
考研英语阅读材料汇编之科技类(2)-毙考题
考研英语阅读材料汇编之科技类(2)阅读是考研英语的重要题型之一，也是保障英语成绩的关键题目。
因此，考研学子们要充分重视英语阅读，除了平时多多阅读英语杂志、报纸外，还需要针对阅读进行专项训练。
小编整理了关于考研英语阅读题源的系列文章考研英语阅读材料汇编之科技类(2)，请参考!Who s the Smart Sibling?Ten weeks ago, Bo Cleveland and his wife embarked on a highly unscientific experiment-they gave birth to their first child. For now, Cleveland is too exhausted to even consider having another baby, but eventually, he will. In fact, hes already planned an egalitarian strategy for raising the rest of his family. Little Arthur won t get any extra attention just because he s the firstborn, and, says his father, he probably won t be much smarter than his future .siblings; either. It s the sort of thing many parents would say, but it s a bit surprising coming from Cleveland,who studies birth order and IQ at Pennsylvania State University. As he knows too well, a study published recently in the journal Science suggests that firstborns do turn out sharper than their brothers and sisters, no matter how parents try to compensate. Is Cleveland wrong? Is Arthur destined to be the smart sibling just because he had the good luck to be born first?For decades, scientists have been squabbling over birth order like siblings fighting over a toy. Some of them say being a first-, middle- or lastborn has significant effects on intelligence. Others say that s nonsense, The spat goes back at least as far as Alfred Adler, a Freud-era psychologist who argued that firstborns had an edge. Other psychologists found his theory easy to believemiddle and youngest kids already had a bad rap, thanks to everything from primogeniture laws to the Prodigal Son. When they set out to confirm the birth-order effects Adler had predicted, they found some evidence. Dozens of studies over the next several decades showed small differences in IQ; scholastic-aptitude tests and other measures of achievement So did anecdata suggesting that firstborns were more likely to win Nobel Prizes or become (ahem) prominent psychologists.But even though the scientists were turning up birth-order patterns easily, they couldn tpin down a cause. Perhaps, one theory went, the mother s body was somehow attacking the lateroffspring in uterus. Maternal antibody levels do increase with each successive pregnancy. Butthere s no evidence that this leads to differences in intelligence, and the new study in Silence,based on records from nearly a quarter of a million young Norwegian men, strikes down theantibody hypothesis. It looks at kids who are the eldest by accident-those whose older siblingsdie in infancy--as well as those who are true firstborns. Both groups rack up the same highscores on IQ tests. Whatever is lowering the latterborns scores, it isn t prenatal biology, sincebeing raised as the firstborn, not actually being the firstborn, is what counts.The obvious culprits on the nurture side are parents. But it s hard to think that favoritism toward firstborns exists in modem society. Most of us no longer view secondborn as second best, and few parents will admit to treating their kids differently. In surveys, they generally say they give their children equal attention. Kids concur, reporting that they feel they re treated fairly.Maybe, then, the problem with latterborns isn t nature or nurture-maybe there simply isn t a problem. Not all the research shows a difference in intelligence. A pivotal 2000 study by Joe Rodgers ,now a professor emeritus at the University of Oklahoma, found no link between birth order and smarts. And an earlier study of American families found that the youngest kids, not theoldest, did best in school. From that work, say psychologist Judith Rich Harris, a prominent critic of birth-order patterns, it s clear that the impression that the firstborn is more often the academic achiever is false.Meanwhile, many of the studies showing a birth-order pattern in IQ have a big, fat,methodological flaw. The Norwegian Science study is an example, says Cleveland: It scomparing Bill, the first child in one family; to Bob, the second child in another family. Thatwould be fine if all families were identical, but of course they aren t. The study controls forvariables such as parental education and family size. But Rodgers, the Oklahoma professor,notes that there are hundreds of other factors in play; and because it s so hard to discountall of them, he s not sure whether the patterns in the Science article are real.No one is more sensitive to that criticism than the Norwegian scientists. In fact, theyalready have an answer ready in the form of a second paper. Soon to be published in thejournal Intelligence, it s, similar to the Science study except for one big thing: instead ofcomparing Bill to Bob, it compares Bill to younger brothers Barry and Barney. The samebirth- order pattern shows up: the firstborns, on average, score about two points higher thantheir secondborn brothers, and hapless thirdborns do even worse. The purpose of thetwo papers was exactly the same, says Petter Kristensen of Norway s National Instituteof Occupational Health, who led both new studies. But this second one is much more comprehensive, and in a sense it s better than the Science paper. The data are there--within families, birth order really does seem linked to brain power. Even the critics have to soften their positions a little. The Intelligence study must be taken very seriously says Rodgers.No one, not even Kristensen, thinks the debate is over For one thing, there s still that argument about what s causing birth-order effects. It s possible, says UC Berkeley researcher Frank Sulloway, that trying .to treat kids in an evenhanded way in fact results in inequity. Well-meaning parents may end up shortchanging middleborns because there s one thing they can t equalize: at no point in the middle child s life does he get to be the only kid inthe house. Alternatively, says Sulloway; there s the theory he has his money on, the family- niche hypothesis Older kids, whether out of desire or necessity axe often called on to be assistant parents, he notes. Getting that early- taste of responsibility may prime them for achievement later on. If they think Oh, I m supposed to be more intelligent so I d betterdo my homework, it doesn t matter if they actually are more-intelligent, says Sulloway, Itbecomes a self-fulfilling prophecy. If the firstborns homework involves reading Science and Intelligence, there ll be no stopping them now.词汇注解重点单词embark / im ba:k/【文中释义】v.着手，从事【大纲全义】v. (使)上船(或飞机，汽车等)：着手，从事extra / ekstr /【文中释义】adj.额外的【大纲全义】adj额外的，附加的n.附加物，额外的东西adv.特别地compensate / kɔmpənseit/【文中释义】v.补偿，弥补【大纲全义】v.(for)补偿，赔偿，抵消nonsense / nɔnsəns/【文中释义】n.荒谬的言行，胡话【大纲全义】n.胡说，废话;冒失(或轻浮)的行为rap / r p/【文中释义】n.不公正的判决，苛评【大纲全义】n.叩击，轻拍，斤责，急敲(声);不公正的判决，苛评，v. 敲，拍，打，斤责，使着迷predict / pri dikt/【文中释义】v.预言【大纲全义】v.预言，预测，预告prominent / prɔminənt/【文中释义】adj杰出的【大纲全义】adj.突起的，凸出的;突出的，杰出的offspring /ɔfspriŋ; (us) ɔ:f-/【文中释义】n..子孙,后代【大纲全义】n. 子孙,后代,结果，产物;(动物的)崽successive /sək sesiv/【文中释义】adj.连续的【大纲全义】adj.接连的，连续的pregnancy / Pregnənsi/【文中释义】n.怀孕【大纲全义】n.妊振;怀孕(期);(事件等的)酝酿;(内容)充实，富有意义nurture / nə: tʃə/【文中释义】n.养育，教育【大纲全义】n.营养品;养育，培养，滋养v. 给予营养物，养育，培养，滋养超纲单词egalitarian n. 平等主义sibling n. 兄弟妞妹squabble v. 为争吵spat n. 争吵primogeniture n. 长子身份aptitude n. 才能，资质anecdata n. 二逸事证据prenatal adj. 产前的，出生前的重点段落译文两周前，伯克利夫兰和他的妻子进行了一项非常不科学的实验他们生下了他们的第一个孩子。
初三科技与未来英语阅读理解25题
初三科技与未来英语阅读理解25题1<背景文章>Artificial intelligence (AI) is playing an increasingly important role in the field of healthcare. AI has the potential to revolutionize medical diagnosis and treatment. One of the main applications of AI in healthcare is in medical imaging. AI algorithms can analyze medical images such as X-rays, CT scans, and MRIs to detect diseases and abnormalities. This can help doctors make more accurate diagnoses and provide better treatment plans.Another application of AI in healthcare is in drug discovery. AI can analyze large amounts of data to identify potential drug candidates and predict their efficacy and safety. This can speed up the drug discovery process and lead to the development of new and more effective treatments.AI also has the potential to improve patient care. For example, AI-powered chatbots can answer patients' questions and provide them with personalized health advice. This can help patients better understand their conditions and take more active roles in their own healthcare.However, the use of AI in healthcare also faces some challenges. One of the main challenges is data privacy and security. Medical data is highly sensitive and needs to be protected from unauthorized access. Anotherchallenge is the lack of transparency and explainability of AI algorithms. Doctors and patients need to understand how AI algorithms make decisions in order to trust them.In conclusion, AI has the potential to bring significant benefits to healthcare, but it also needs to overcome some challenges in order to realize its full potential.1. What is one of the main applications of AI in healthcare?A. Medical education.B. Medical imaging.C. Hospital management.D. Patient transportation.答案：B。
PhysRevA.70.052320
Unconventional geometric quantum phase gates with a cavity QED system
Shi-Biao Zheng*
Department of Electronic Science and Applied Physics, Fuzhou University, Fuzhou 350002, China (Received 14 January 2004; revised manuscript received 5 April 2004; published 19 November 2004) We propose a scheme for realizing two-qubit quantum phase gates via an unconventional geometric phase shift with atoms in a cavity. In the scheme the atoms interact simultaneously with a highly detuned cavity mode and a classical field. The atoms undergo no transitions during the gate operation, while the cavity mode is displaced along a circle in the phase space, aquiring a geometric phase conditional upon the atomic state. Under certain conditions, the atoms are disentangled with the cavity mode and thus the gate is insensitive to both the atomic spontaneous emission and the cavity decay. DOI: 10.1103/PhysRevA.70.052320 PACS number(s): 03.67.Lx, 03INTRODUCTION
扫描隧道显微镜
国 家 数 自 理 hv 然 学 科 e 部 学 实 基 验 金 物 委 理 }员 讲 会 习 班 I=I + I
Definition: STM Induced Luminescence (STML) Beyond imaging and manipulation Elastic Tunneling Process:
Theoretical calculations
国 Introduction to the Background Brief 家 数 自 理 然 学 科 部 学 Experimental Techniques 实 基 验 金 物 委 Status of STM Induced Luminescence 员 理 讲 会 习 班
_
hv
原子分辨 STM
+
e–
ET
e–h
单光子计数 Optical Detectors
h+
recombination
HT
空间、能量、时间 高分辨
+
能量转化动力学
纳米元件、生物分子识别？
国分子尺度调控研究的多功能复合技术 家 数 自 理 扫描探针技术 伏安曲线测量 光学技术 然 学 科 部 学 实 基 验 金 物 委 + “Z” (X,Y) (X,Y) 理 (X,Y) + I-V 员 讲 + dI/dV 会 (X,Y) 习 (X,Y) 班 I/dV + d
Interface parameter control for organic electronics (e.g., OLED, η↑) Spectral imaging of single defects or impurities in electronic devices Radiative decay engineering for bio-molecular (DNA) mapping Nanoscale light source for optical spectroscopy and imaging Single-molecule electroluminescence and single-photon sources
nature
本科生科研训练题目高能量密度柔性赝电容器中的二维磷酸氧钒超薄结构（翻译）院系物理科学与技术学院专业物理学基地班年级2012级学生姓名李赫学号**********二0一三年十二月二十日natureCOMMUNICATIONS2013年2月5号收到稿件2013年8月12日接受稿件2013年9月12日发表稿件DOI: 10.1038/ncomms3431高能量密度柔性赝电容器中的二维磷酸氧钒超薄结构二维材料一直以来在柔性薄膜型超级电容器，以及表现有关灵活性，超薄度甚至透明度的强劲优势上都是一个理想的构建平台。
要探索新的具有高电化学活性的二维赝电容材料，我们需要获得具有高能量密度的柔性薄膜超级电容器。
这里我们介绍一个无机石墨烯类似物，a1钒，一种少于6个电子层的磷酸盐超薄纳米片来作为一个有发展前景的材料去构建柔性全固态超薄赝电容器。
这种材料展示了一个在水溶液中氧化还原电位(~1.0V)接近纯水电化学窗口电压（1.23V）的赝电容柔性平面超级电容器。
通过层层组装构建出的柔性薄膜型超级电容器的氧化还原电位高达1.0V，比容量高达8360.5 μF∙cm-2，能量密度达1.7 mWh ∙cm-2，功率密度达5.2 mW∙cm-2。
现在，便携式消费电子产品的需求在快速增长，如柔性显示器，手机和笔记本电脑，极大推动了在全固态下的柔性能源设备的开发。
作为未来一代的储能装置，柔性薄膜型超级电容器在全固态下提供柔韧性，超薄型和透明度的协同效益。
在不同的类型的超级电容器中，与电双层电容器相比，赝电容器因为自身的高活性表面的电极材料可以快速发生的氧化还原反应而具有明显优势。
与锂离子电池相比，它表现出更高的能量密度，以及更高的功率密度。
因此，承载着为实现高性能的柔性薄膜型超级电容器的全固态伟大的承诺（FUSA）与电容行为。
具有赝电容特性的二维（2D）类石墨烯材料代表着一个有前途的方向可以去实现全固态下的高能量密度柔性超级电容器，和潜在的优良的机械柔性。
Evolution of Ge and SiGe Quantum Dots under Excimer Laser Annealing
CHIN.PHYS.LETT.Vol.25,No.1(2008)242 Evolution of Ge and SiGe Quantum Dots under Excimer Laser Annealing∗HAN Gen-Quan(韩根全)1∗∗,ZENG Yu-Gang(曾玉刚)1,YU Jin-Zhong(余金中)1,CHENG Bu-Wen(成步文)1,YANG Hai-Tao(杨海涛)21State Key Laboratory on Integrated Optoelectronics,Institute of Semiconductors,Chinese Academy of Sciences,Beijing1000832Tsinghua-Foxconn Nanotechnology Research Center,Department of Physics,Tsinghua University,Beijing100084(Received15September2007)We present different relaxation mechanisms of Ge and SiGe quantum dots under excimer laser annealing.Inves-tigation of the coarsening and relaxation of the dots shows that the strain in Ge dots on Gefilms is relaxed by dislocation since there is no interface between the Ge dots and the Ge layer,while the SiGe dots on Si0.77Ge0.23film relax by lattice distortion to coherent dots,which results from the obvious interface between the SiGe dots and the Si0.77Ge0.23film.The results are suggested and sustained by Vanderbilt and Wickham’s theory,and also demonstrate that no bulk diffusion occurs during the excimer laser annealing.PACS:68.65.Hb,68.35.Fx,68.35.Md,68.37.PsGe and SiGe self-assembled quantum dots (SAQDs)are widely studied for their promis-ing application in optoelectronics due to three-dimensional(3D)quantum confinement.[1]Many works have focused on the growth mechanism,[2,3] shape transition,[4,5]and the coarsening process under thermal annealing[6]of the SAQDs in S-K mode.Re-cently,we obtained SiGe quantum dots with small size and high density by excimer laser annealing(ELA).[7] The nanosecond pulse duration of the excimer,which induces rapid heating and cooling of the sample sur-face,ensuring that the laser induced quantum dots (LIQDs)are formed only by surface atoms diffusion.[8] We obtained Ge and SiGe laser induced quantum dots by ELA of the Ge and SiGefilms,respectively.In this Letter,we report that the laser-induced Ge and SiGe quantum dots undergo different relax-ation mechanisms.Atomic-force-microscopy(AFM) measurements indicate that the Ge LIQDs on the Ge film relax by formation of dislocation,while the SiGe LIQDs on the Si0.77Ge0.23film release the strain by the lattice tetragonal distortion and then form coher-ent dots.The theory developed by Vanderbilt and Wickham has shown[9]that the interface between the dots and the wetting layer plays a pivotal role in the relaxation process of the strained dots.For the SiGe LIQDs on the Si0.77Ge0.23film,our calculation shows that SiGe quantum dots with the Ge composition of about83%are formed on the Si0.77Ge0.23film,which indicates an obvious interface between the dots and the Si0.77Ge0.23film.The interface leads to the for-mation of the coherent SiGe relaxed dots.However, for the Ge LIQDs on the Gefilm,no interface between the dots and the wetting layer results in the formation of the dislocated dots.These are suggested and sus-tained by Vanderbilt and Wickham’s theory,and also demonstrates that no bulk diffusion occurs during the excimer laser annealing.The Ge and SiGefilms were grown by an ultra-high-vacuum chemical vapour deposition(UHV-CVD) system on(001)-oriented Si substrates at500◦C and 550◦C,respectively.The Gefilm is in thickness of about1nm(8monolayers),and the SiGefilm is about 20nm.The sources of Si and Ge are disilane and ger-mane,respectively.The Si substrates were cleaned in an ex-situ chemical etch process and loaded into an UHV growth chamber with basic pressure lower than 10−7Pa,and then heated up to950◦C to deoxidize. The thickness and Ge composition of the Si0.77Ge0.23film are determined by double-crystal x-ray diffraction (XRD).A193nm ArF excimer laser operating frequency in 40Hz,was used to ex-situ anneal the samples,which were annealed in argon ambient.A top-flat beam profile of10×10mm2with the energy density of about180mJ/cm2was obtained by using a homog-enizer.This was carried out to ensure uniform an-nealing of samples’surface.The surface morphology of the samples was measured by an SPA-300HV AFM, performed in tapping mode.Figure1shows the AFM images of Ge and SiGe LIQDs obtained by ELA of Ge and Si0.77Ge0.23films, respectively.The height profiles of the dots are also in Fig.1.The diameters of the Ge and SiGe LIQDs are20–25nm and15–20nm,respectively.The ther-mal process induced by the excimer laser pulse is only several tens nanoseconds,so during the ELA,only surface diffusion occurs.The dot energy can be ex-pressed by E=4ΓV2/3tan1/3θ−6AV tanθ,[2]where Γ=γd cscθ−γs cotθis the increase of surface energy,∗Supported by the National Natural Science Foundation of China under Grant No60576001.∗∗Email:hgquan@c 2008Chinese Physical Society and IOP Publishing LtdNo.1HANGen-Quan et al.243γs and γd are the surface energy per unit area of the wetting layer and dot facet,respectively,θis the facet angle with respect to the surface of the wetting layer,V is the volume of the dot,A =σ2(1−ν)/(2πG )where σis the in-plane misfit strain,and νand G are Poisson’s ratio and shear modulus,respectively.For the LIQDs,only surface energy should be stud-ied,and the second term on the right can be con-sidered as the effect of strain on the surface energy.From the formula,we can see that the slightly strained dots are not stable during the ELA.We speculate that the heavily strained LIQDs will grow,relax the strainin them with longer annealing time.To investigate the relaxation of the LIQDs,we prolong the anneal-ing time with the laser energy density of 180mJ/cm 2.As the ELA continues,We observe the relaxation and the shrinking of the LIQDs,while it is surprisingly found that Ge quantum dots on the Ge wetting layer and SiGe dots on the Si 0.77Ge 0.23layer underwent the different relaxation modes:the Ge dots relax through the formation of the dislocation,while the strain in the SiGe quantum dots on the Si 0.77Ge 0.23wetting layer is released by lattice tetragonal distortion.Fig.1.AFM images (500nm ×500nm)of LIQDs:(a)Ge LIQDs on the Ge film and the height profiles along the line marked,(b)SiGe LIQDs on the Si 0.77Ge 0.23film and the height profiles along the line marked.Figure 2shows a series of AFM images of the mor-phology of Ge LIQDs on the Ge film at different an-nealing times.When the annealing time is prolonged to 3.5hours,coarsening of the quantum dot,as shown in Fig.2(a),occurs.The contacting of the small and large dots in Fig.2(a)and 2(b)can be interpreted to be the losing materials of small dots to the near large dots,which is analogous to the anomalous coarsening in the SAQDs.[10]As the ELA proceeds,the density of the dots further decreases,and when the annealing time is up to 5hours,almost all the LIQDs disappear (shown in Fig.2(c)).After 7-h ELA,no new LIQDs are observed.We speculate that the relaxation of the laser induced Ge dots is by the dislocations and the strained film is also relaxed by the dislocations.Fig-ure 3shows the schematic of the relaxation process ofthe Ge quantum dots on the Ge film.Figure 4(a)shows the coarsening and the growth of the SiGe dots on the Si 0.77Ge 0.23film.After 4-h an-nealing,the SiGe dots become larger and the density decreases.As the annealing continues (5h),some new LIQDs appear.This indicates that the growth and disappearing of the SiGe dots give rise to the restora-tion of the strain in the Si 0.77Ge 0.23film.This will decrease the surface energy and increase the strain en-ergy.The recovered stress in the film drives the new LIQDs under ELA.This reveals that the SiGe dots grow and relax to be the coherent dots,i.e.,the strain in the SiGe dots is relaxed by the lattice distortion.Figure 5shows the schematic of the relaxation process of the SiGe quantum dots on the Si 0.77Ge 0.23film.244HAN Gen-Quan et al.Vol.25Fig.2.AFM images (1µm ×1µm)of the Ge LIQDs on the Ge film with different annealing times:(a)annealed for 3.5h,(b)annealed for 4h,(c)annealed for 5h,(d)annealed for 7h.Fig.3.Schematic diagram of the relaxation mode of the Ge quantum dots on the Ge film.Fig.4.AFM images (1µm ×1µm)of the SiGe LIQDs on the Si 0.77Ge 0.23film for different annealing times:(a)annealed for 4h,(b)annealed for 5h.These results reveal the existence of two different relaxation mechanisms:generation dislocation in the dots and formation coherent relaxed dots.When the quantum dots grow,the relaxation of quantum dots is the competing of the lattice distortion (coherent re-laxed dots)with the formation of the dislocation (dis-located relaxed dots).The theory developed by Van-derbilt and Wickham [9]compares the two mechanisms of elastic relaxation and yields a phase diagram of a lattice mismatched system in which all possible mor-phologies are present,i.e.,uniform films,dislocated dots,and coherent dots.No.1HAN Gen-Quan et al.245It was shown by Vanderbilt and Wickham that morphology of the mismatched system is determined by the ratio of the energy of interface between dots and the wetting layer (E interface )to the change of the sur-face energy (∆E surf ).[9]The deposited material wets the substrate firstly,and then the 2D strained film transforms to the 3D quantum dots.If ∆E surf is posi-tive and large,or if the energy of the interface between the dots and the wetting layer is relatively small,the formation of coherently strained dots is not favoured.With an increase in the amount of deposited material,a transition occurs from uniform film to dislocated dots,and the coherently strained dots are not formed.If ∆E surf is positive and small,or if the energy of the dislocated interface is relatively large,with an increase in the amount of deposited material,a transition oc-curs from a uniform film to coherent dots.Further de-position may cause the onset of dislocations.The de-tailed calculation and the phase diagram can be found in Ref.[9].Fig.5.Schematic diagram of the relaxation process of the SiGe quantum dots on the Si 0.77Ge 0.23film.This theory can be used to interpret the differ-ent relaxation modes of the Ge and SiGe dots.It is sure that the pyramidal laser induced Ge dots,with the diameter of about 20–25nm and density of about 6×1010cm −2,do not exhaust the Ge film with the thickness more than 1nm (8monolayers).Because no bulk diffusion occurs during the annealing,atoms intermixing between the dots and the wetting layer need not be considered.We think that the pure Ge LIQDs are formed on the Ge film,i.e.,there is no in-terface between the dots and the wetting layer.For the SiGe LIQDs on the Si 0.77Ge 0.23film,based on the surface chemical potential calculation,we show that the heavily strained SiGe quantum dots must have a misfit above 0.035corresponding to a Ge composi-tion of about 83%,to promise E surf <0(the dots stable under ELA).[7]This indicates the SiGe dots are Ge richer than the Si 0.77Ge 0.23film,which also results from that the surface diffusion coefficient of Ge is 102–103times greater than that of Si.[11]If the atoms interdiffusion is neglected,there should be an obvious interface between the SiGe quantum dots and the Si 0.77Ge 0.23wetting layer.It is suggested theoret-ically by Vanderbilt and Wickham and supported by our experiments that the interface between the quan-tum dots and the wetting layer plays a pivotal role in the competition between the lattice distortion and the formation of dislocation.Vanderbilt and Wickham’s theory is proven by our results and also confirms and enforces our previous conclusion that the pure Ge dots and an abrupt inter-face between the dots and wetting layer are availablewhich is attributed to no bulk atoms diffusion under ELA.In conclusion,we have studied the different relax-ation mechanisms of the Ge and SiGe quantum dots on Ge and Si 0.77Ge 0.23films,respectively,under ELA.We recover the pivotal role of the interface between the dots and the wetting layer.The relaxation of Ge dots by dislocation is attributed to no interface between Ge dots and the Ge layer,and that of SiGe dots by lattice tetragonal distortion results from the obvious interface between SiGe dots and the Si 0.77Ge 0.23film.This is sustained by Vanderbilt and Wickham’s theory.References[1]Baribeau J M,Wu X,Rowell N L and Lockwood D J 2006J.Phys.:Condens.Matter 18R139[2]TersoffJ and LeGoues F K 1994Phys.Rev.Lett.723570[3]Sutter P,Schick I,Ernst W and Sutter E 2003Phys.Rev.Lett.91176102[4]Rastelli A,Stoffel M,TersoffJ,Kar G S and Schimidt O G2005Phys.Rev.Lett.95026103[5]Montalenti F,Raiteri P,Migas D B,von K¨a nel H,RastelliA,Manzano C,Costantini G,Denker U,Schimidt O G,Kern K and Miglio L 2004Phys.Rev.Lett.93216102[6]Kamins T I,Medeiros-Ribeiro G,Ohlberg D A A andWilliams R S 1999J.Appl.Phys.851159[7]Han G Q,Zeng Y G,Yu J Z,Cheng B W and Yang H T2007J.Cryst.Growth (submitted)[8]Misra N,Xu L,Pan Y L,Cheung N and Grigoropoulos CP 2007Appl.Phys.Lett.90111111[9]Vanderbilt D and Wickham L K 1991Mater.Res.Soc.Symp.Proc.202555[10]Rastelli A,Stoffel M,TersoffJ,Kar G S and Schmidt O G2005Phys.Rev.Lett.95026103[11]Huang L,Liu F,Lu G-H and Gong X G 2000Phys.Rev.Lett.96016103。
2023届高考英语阅读理解人与社会—科学与技术(科技发展与信息技术创新)试题
2023届高考英语阅读理解人与社会—科学与技术（科技发展与信息技术创新）试题Quantum (量子) computers have been on my mind a lot lately. A friend has been sending me articles on how quantum computers might help solve some of the biggest challenges we face as humans. I’ve also had exchanges with two quantum-computing experts. One is computer scientist Chris Johnson who I see as someone who helps keep the field honest. The other is physicist Philip Taylor.For decades, quantum computing has been little more than a laboratory curiosity. Now, big tech companies have invested in quantum computing, as have many smaller ones. According to Business Weekly, quantum machines could help us “cure cancer, and even take steps to turn climate change in the opposite direction.” This is the sort of hype (炒作) that annoys Johnson. He worries that researchers are making promises they can’t keep. “What’s new,” Johnson wrote, “is that millions of dollars are now potentially available to quantum computing researchers.”As quantum computing attracts more attention and funding, researchers may mislead investors, journalists, the public and, worst of all, themselves about their work’s potential. If researchers can’t keep their promises, excitement might give way to doubt, disappointment and anger, Johnson warns. Lots of other technologies have gone through stages of excitement. But something about quantum computing makes it especially prone to hype, Johnson suggests, perhaps because “‘quantum’ stands for something cool you shouldn’t be able to understand.” And that brings me back to Taylor, who suggested that I read his book Q for Quantum.After I read the book, Taylor patiently answered my questions about it. He also answered my questions about PyQuantum, the firm he co-founded in 2016. Taylor shares Johnson’s concerns about hype, but he says those concerns do not apply to PyQuantum.The company, he says, is closer than any other firm “by a very large margin (幅度)” to building a “useful” quantum computer, one that “solves an impactful problem that we would not have been able to solve otherwise.” He adds, “People will naturallydiscount my opinions, but I have spent a lot of time quantitatively comparing what we are doing with others.”Could PyQuantum really be leading all the competition “by a wide margin”, as Taylor claims? I don’t know. I’m certainly not going to advise my friend or anyone else to invest in quantum computers. But I trust Taylor, just as I trust Johnson.1. Regarding Johnson’s concerns, the author feels .A. sympatheticB. unconcernedC. doubtfulD. excited2. What leads to Taylor’s optimism about quantum computing?A. His dominance in physics.B. The competition in the field.C. His confidence in PyQuantum.D. The investment of tech companies.3. What does the underlined word “prone” in Paragraph 3 most probably mean?A. Open.B. Cool.C. Useful.D. Resistant.4. Which would be the best title for the passage?A. Is Johnson More Competent Than Taylor?B. Is Quantum Computing Redefining Technology?C. Will Quantum Computers Ever Come into Being?D. Will Quantum Computing Ever Live Up to Its Hype?Keys:1-4 ACAD拓展练习I. Complete the following sentences with the correct forms of the given words.1. Sophie’s __________ (curious) was picked by the strange phone call.2. Mountain climbing is becoming a popular sport, but it is also a __________ (potential) dangerous one.3. The man’s 50-year-old life may have been short, but it was __________ (impact): He made a very positive contribution to society.II. Translate the following sentences using the words and phrases in brackets.1. 丽莎常常工作到深夜，仅靠面包、黄油和茶果腹。
quantumultx 流利说英语
quantumultx 流利说英语Quantum computing is a rapidly evolving field of study that has the potential to revolutionize the way we process and store information. At the heart of this technology lies the concept of quantum mechanics, which describes the behavior of particles at the subatomic level. Unlike classical computers, which rely on binary digits (bits) to represent information, quantum computers utilize quantum bits, or qubits, to perform computations.The fundamental difference between classical and quantum computing lies in the way information is stored and processed. In a classical computer, a bit can exist in one of two states: 0 or 1. In contrast, a qubit can exist in a superposition of both 0 and 1 states simultaneously, a property known as quantum superposition. This allows quantum computers to perform certain computations exponentially faster than their classical counterparts, particularly in areas such as cryptography, optimization, and simulation.One of the key challenges in the development of quantum computers is the delicate nature of qubits. Qubits are highly susceptible to environmental interference, which can cause them to lose their quantum state, a phenomenon known as decoherence.This fragility has led to the development of various techniques and technologies aimed at maintaining the integrity of qubits, such as quantum error correction and the use of specialized materials and environments.Despite these challenges, the potential benefits of quantum computing are immense. Quantum computers could be used to solve complex problems that are currently intractable for classical computers, such as the simulation of chemical and biological processes, the optimization of complex systems, and the breaking of certain types of cryptographic algorithms.The development of quantum computing has also led to the emergence of a new field known as quantum cryptography, which focuses on the secure transmission of information using the principles of quantum mechanics. Quantum cryptography relies on the fundamental properties of quantum particles, such as their ability to be in a superposition of states, to ensure the security of communication channels.One of the key applications of quantum cryptography is the development of quantum-resistant encryption algorithms, which are designed to withstand attacks from quantum computers. As the power of quantum computers continues to grow, traditional encryption methods may become vulnerable, making thedevelopment of quantum-resistant cryptography a critical priority for governments and businesses around the world.In addition to its applications in cryptography and computation, quantum computing also has the potential to revolutionize fields such as sensing and metrology. Quantum sensors, for example, can be used to measure extremely small changes in magnetic fields, gravitational fields, and other physical quantities with unprecedented precision. This could lead to advancements in fields such as navigation, geology, and medical imaging.Despite the significant progress made in the field of quantum computing, there is still much work to be done before it becomes a practical and widely-adopted technology. Researchers and engineers around the world are working to overcome the challenges posed by the fragility of qubits, the development of scalable quantum hardware, and the integration of quantum computers with classical computing systems.One of the key drivers of progress in quantum computing is the continued investment and collaboration between governments, industry, and academia. Many countries have established national quantum initiatives, providing funding and support for research and development in this critical field. Additionally, major tech companies and startups are investing heavily in quantum computing,recognizing its potential to transform a wide range of industries.As the field of quantum computing continues to evolve, it is clear that it will have a profound impact on our lives in the years to come. From the development of more secure communication channels to the solution of complex problems that were previously intractable, quantum computing has the potential to unlock new frontiers of scientific and technological advancement. By embracing this transformative technology, we can pave the way for a future that is more efficient, more secure, and more innovative than ever before.。