| 查看: 477 | 回复: 2 | |||
[交流]
【求助】求解几道半导体物理材料题（英文）
|
|
Useful constants: kB = 1.38× 10-23 J/K, c = 2.998 x 108 m/s, h= 6.626 x 10-34 J-s, m= 9.109 x 10-31 kg, e = 1.602 x10-19 C 1. Materials in the nanometer scale exhibit physical properties quite different from bulk materials. A. Crystals in the nanometer scale have a lower melting temperature and the difference can be as large as 1000 °C. Why? B. Surface energy (γ) can be defined as the energy required to create a unit area of “new” surface. Considering that two new surfaces can be crated by separating solid materials into two pieces, define the surface energy of {100} surface in FCC crystal? Here the atomic bond strength is ε. C. The surface energies calculated from (b) exhibit some deviation from experimental data, and this is can be understood by the surface energy reduction mechanism. Name 4 ‘surface energy reduction mechanisms’. 2. As shown in Fig.1, an electron is trapped in a one-dimensional energy well of width L with rigid walls. Here, time-independent Schrödinger equation that can describe the motion of electrons is given by,  and the general wave solution in region II is given by,  A. Determine k, A2, and B2. B. Determined the allowed energy levels (En) in Region II. C. For L = 1 nm, calculate wavelengths of the two lowest-energy photons capable of exciting electrons from the ground state. D. Calculate the maximum well width, L that can ensure us the observation of electron transition between the two lowest energy levels at T = 300K. E. If photoluminescent (PL) spectra from InP microcrystals and InP nanowire (diameter, d = 50 nm) exhibit the dominant near band-edge (NBE) peaks at 1.45 eV, and 1.47 eV, respectively. Then, estimate the energy of NBE peak from 10 nm thick InP nanowire? (Ignore the Coulomb interaction.)  3. In mesoscopic systems in which electron transport is confined to a single dimension, quantized conductance can be observed. A. Name two necessary conditions to observe quantized conductance in electron transport? B. Figure 2 shows the experimental arrangement needed to generate the required 1D constriction in electron flow pattern. Sketch the data for electrical conductance, G = I/ΔV, of the structure as a function of gate voltage, Vg.  Fig. 2 4. A Single-wall nanotube (SWNT) is formed by rolling a graphene sheet into a cylinder along an helicity vector, (n, m) in the graphene plane (Fig. 3). A. Name three types of SWNTs based on the way to roll the graphene sheet into a nanotube along with their helicity vectors, (n, m) and angles of helicity, θ. B. Calculate the diameter of the SWNT that has the helicity vector of (10, 0). [hint: the C-C bond length, aC=C = 1.42 Å] C. Calculate the diameter of the SWNT that has the helicity vector of (4, 4).  [ Last edited by 小木虫  on 2010-12-24 at 01:32 ] |
回复此楼» 猜你喜欢
综述论文作为代表作会不会影响评审专家的印象分？
已经有12人回复
-
2019年青年基金涵评意见，大家看看几个A，几个B?
已经有4人回复
-
应该是93bebmhtak前后十一个字符比较关键
已经有29人回复
-
奇怪，两个人的filecode固定段从头到尾一模一样
已经有9人回复
-
是这周出结果还是下周出结果？
已经有3人回复
-
小木虫上这么多卖论文的，真有人买论文么？感觉没必要啊
已经有9人回复
-
有时候，自然基金真的不能太认真 （我的申报经验）
已经有4人回复
-
帮忙看看fileCode
已经有13人回复
-
为什么网上很多人说本周 12号出结果
已经有7人回复
-
读博的好处
已经有3人回复
» 本主题相关商家推荐: (我也要在这里推广)
» 抢金币啦！回帖就可以得到:
-
武汉女征男
+2/216
-
胆酸锂 （Lithium cholate）
+1/88
-
西安交大马伟/王亚洲课题组诚聘联培学生多名/科研助理/博士-有机生物电子学方向
+1/88
-
招聘机械领域专利代理人
+1/77
-
天津大学环境学院童银栋教授招收博士后（生源要素循环/温室效应/新污染物方向）
+1/33
-
哈尔滨工业大学郑州高等研究院查正宝研究员招收博士/硕士
+1/29
-
同济大学环境学院肖倩课题组2026年补充招收推免生
+1/26
-
中国石油大学（华东）计算机科学与技术学院/智能化新能源系统设计和开发方向 特聘副教
+2/26
-
哈工大（深圳）何自开团队诚招化学工程与技术专业博士生
+1/24
-
南京航空航天大学招收27年力学硕士和博士生研究生
+1/14
-
求相关合成条件
+1/14
-
中科院理化所热声热机团队招聘电气工程专业(电机方向)博士后/特别研究助理
+1/14
-
北理工集成电路杰青团队 | 诚招科助理
+1/11
-
北京理工大学-集成电路与电子学院杰青团队-招博士后
+1/9
-
海南大学化学院—功能分子器件团队2027博士招生+博士后招聘
+1/9
-
希望大家都高中！！
+1/7
-
中山大学李国强课题组招收博士生（柔性电子方向）
+1/5
-
Luminex 多因子定量解析 CAR-T 铁死亡调控抗肿瘤免疫疗效
+1/4
-
请大家抽空欣赏一下我们网站的配图
+1/2
-
悉尼科技大学（QS 第87）数据科学/AI招收2027年秋季入学全奖及CSC博士生
+1/1
孙?�730
至尊木虫 (知名作家)
- 物理EPI: 7
- 应助: 537 (博士)
- 贵宾: 0.961
- 金币: 23065.7
- 散金: 6464
- 红花: 177
- 沙发: 16
- 帖子: 8218
- 在线: 2903.3小时
- 虫号: 490447
- 注册: 2008-01-03
2楼2010-12-13 12:33:22
3楼2010-12-13 13:07:40
