Relative enhancement of photoluminescence intensity of passivated silicon nanocrystals in a silicon dioxide matrix

Photoluminescence (PL) intensity of passivated silicon nanocrystals (Si NCs) embedded in a SiO 2 matrix is compared with that of unpassivated Si NCs. We investigate the relative enhancement of PL intensity (I R ) as a function of annealing temperature and implanted Si ion dose. The I R increases simultaneously with the annealing temperature. This demonstrates an increase in the number of dangling bonds (DBs) with the degree of Si crystallization varying via the annealing temperature. The increase in I R with implanted Si ion dose is also observed. We believe that the near-field interaction between DBs and neighboring Si NCs is an additional factor that reduces the PL efficiency of unpassivated Si NCs.     

傅立叶变换激光腔内吸收光谱方法研究吸收谱线的强度与线形

在原有傅立叶变换激光腔内吸收光谱实验装置的基础上,利用信号差分方法减少了光强波动对实验干涉谱图的影响,改善了信噪比.通过对大气中氧气在760nm处的吸收谱线的绝对强度测量,验证了该方法的定量测量能力.在不同压力条件下对磷烷v=6伸缩局域模泛频吸收谱带进行了测量,获得了其谱线的自压力加宽和自压力线移参数.     

邻井距离随钻电磁探测系统的设计与实现

虚拟二维激光雷达是激光雷达扩展应用的组成部分,可以结合3D场景点云特征进行二维激光雷达扫描障碍物模拟。提出根据光线传导特征建立积分方程得到了在多障碍物场景下的激光雷达图生成的解析解,利用AutoCAD与Visual C#联合编程的方法进行了虚拟激光雷达的实现。最后,实验结果与真实二维激光雷达比对,虚拟激光雷达能从3D场景中准确提取物体的位置和距离信息。     

The optical phonon effect of quantum rod qubits

The Hamiltonian of a quantum rod with an ellipsoidal boundary is given by using a coordinate transformation in which the ellipsoidal boundary is changed into a spherical one.Under the condition of strong electron-longitudinal optical phonon coupling in the rod,we obtain both the electron eigenfunctions and the eigenenergies of the ground and first-excited state by using the Pekar-type variational method.This quantum rod system may be used as a two-level qubit.When the electron is in the superposition state of the ground and first-excited states,the probability density of the electron oscillates in the rod with a certain period.It is found that the oscillation period is an increasing function of the ellipsoid aspect ratio and the transverse and longitudinal effective confinement lengths of the quantum rod,whereas it is a decreasing function of the electron-phonon coupling strength.     

库仑场对量子线中强耦合极化子性质的影响

采用改进的线性组合算符法研究了库仑场对抛物量子线中强耦合极化子性质的影响。计算了抛物量子线中强耦合束缚极化子的基态能量、振动频率和声子平均数。讨论了这些量对库仑束缚势和约束强度的依赖关系。数值计算结果表明：量子线中强耦合束缚极化子的基态能量随库仑束缚势的增加而减少,随约束强度的增加而增大;振动频率和电子周围的光学声子平均数均随库仑束缚势的增加而增加。     

Mechanism and enhancement of photoluminescence from silicon nanocrystals implanted in SiO2 matrix

Photoluminescence (PL) spectra of Si nanocrystals (NCs) prepared by 130 keV Si ions implantation onto SiO2 matrix were investigated as a function of annealing temperature and implanted ion dose. PL spectra consist of two PL peaks, originated from smaller Si NCs due to quantum confinement effect (QCE) and the interface states located at the surface of larger Si NCs. The evolution of number of dangling bonds (DBs) on Si NCs was also investigated. For hydrogen-passivated samples, a monotonic increase in PL peak intensity with the dose of implanted Si ions up to 3×1017 ions /cm2 is observed. The number of DBs on individual Si NC, the interaction between DBs at the surface of neighbouring Si NCs and their effects on the efficiency of PL are discussed.     

Relative enhancement of photoluminescence intensity of passivated silicon nanocrystals in silicon dioxide matrix

Photoluminescence (PL) intensity of passivated silicon nanocrystals (Si NCs) embeded in an SiO₂ matrix is compared with that of unpassivated ones. We investigate the relative enhancement of PL intensity (I_R) as a function of annealing temperature and implanted Si ion dose. The I_R increases simultaneously with the annealing temperature. This demonstrates an increase in the number of dangling bonds (DBs) with the degree of Si crystallization via varying the annealing temperature. The increase in I_R with implanted Si ion dose is also observed. We believe that the near-field interaction between DBs and neighboring Si NCs is an additional factor that reduces the PL efficiency of unpassivated Si NCs.