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1.
研究了在控制和探测激光存在时回音壁腔光机械系统中的动力学行为,分析了系统中产生类似于原子电磁诱导透明与吸收的原因,论证了此系统的输出场在探测频率下存在类似于电磁诱导透明和电磁诱导吸收的现象,并证实了回音壁光机械腔系统与Λ原子系统中的泵浦探测响应特性相类似.此外,利用泵浦失谐控制光机械系统中类似于电磁诱导透明和电磁诱导吸收之间的转换,此系统中光机械诱导透明与吸收的论证为量子信息的处理提供了理论依据.  相似文献   

2.
当K-型五能级原子的两基态能级邻近简并时,连接基态的两个跃迁路径与同一个真空场辐射场相互作用导致的量子干涉效应便产生了空场诱导相干性。K-型五能级原子系统的单光子和双光子电磁诱导透明受空场诱导相干性的作用效果十分明显,单光子吸收性质与外加相干光场的相对相位也有直接联系。  相似文献   

3.
五能级原子系统中的双光子双重电磁诱导透明   总被引:3,自引:1,他引:2  
利用半经典理论,讨论了五能级原子系统中的双光子双重电磁诱导透明,研究了外加相干场的Rabi频率和失谐量对双光子吸收谱的影响,最后在缀饰态中对这些现象给出了解释.  相似文献   

4.
王成会  林书玉 《中国科学(G辑)》2009,39(12):1746-1753
从流体力学基本方程出发,推导了介质中的波动方程,并结合液体介质在声传播过程中的边界条件特征,考虑非线性驻波的物理特性,利用微扰法导出了非线性驻波的基波和二次谐波的稳定表达式.利用水听器测量超声清洗槽内声压,探讨水听器接收电压随超声波发生器输出电压间的关系,证明了槽内声波非线性效应的存在,又根据水听器接收信号的频谱分析,证明了基波和二次谐波以及高次谐波共存于有界空间的液体中.理论和实验结果共同证明非线性驻波的存在.由于微扰法理论本身适用性的限制,我们得到的基波和二次谐波结果只适用于弱非线性驻波.  相似文献   

5.
简要介绍了基于隧穿诱导的固有相干性,耦合量子点系统的非线性光学性质受到干涉效应的影响和变化,及其隧穿测量方面的一些应用。探究了自克尔非线性色散谱对隧穿失谐的灵敏特性,考察了交叉克尔非线性相移对隧穿效应的传感特性,数值模拟结果显示自克尔非线性测量隧穿失谐的精确度可达0.2μeV、系统的交叉相位调制约为0.28rad/μeV;课题组又进一步分析了非线性吸收谱,对隧穿的响应范围为10GHz数量级,并且比较了强弱隧穿情况下,非线性吸收谱对隧穿失谐量的灵敏度的变化,如弱耦合时,吸收谱灵敏度约为3.8μeV;强耦合时,灵敏度大大提高,约为0.4μeV;实现了基于隧穿诱导干涉效应直接提高高阶非线性的方案;提出了利用失谐增强的非线性增益谱表征隧穿变化。  相似文献   

6.
研究了双模SU(1,1)相干态场与Λ型三能级原子非共振相互作用系统中场模失谐量、Kerr介质以及原子初态对光场的二阶相干度的影响.结果表明:Kerr介质对光场二阶相干度不产生明显的影响;场模失谐量减弱原子初态对模场1的影响,增大原子初态对模场2的影响;原子初始状态对光场两模的二阶相干度都有影响,但其对模场2的影响较其对模场1的影响更强.  相似文献   

7.
研究了双模SU(1,1)相干态场与ν↑型三能级原子非共振相互作用系统中场模失谐量、Kerr介质以及原子初态对光场的二阶相干度的影响。结果表明:Kerr介质对光场二阶相干度不产生明显的影响;场模失谐量减弱原子初态对模场1的影响,增大原子初态对模场2的影响;原子初始状态对光场两模的二阶相干度都有影响,但其对模场2的影响较其对模场1的影响更强。  相似文献   

8.
纠缠双原子与光场非共振作用中场的反聚束效应   总被引:1,自引:1,他引:0  
采用全量子论和数值计算的方法,研究了处于耗散腔中的纠缠双原子与相干光场非共振相互作用系统中场的反聚束效应.讨论了初始光场平均光子数、光场与原子间的失谐量和腔场的衰减常数对光场反聚柬效应的影响.结果表明,初始光场的平均光子数对光场的反聚束效应存在显著影响:当初始光场较弱时,光场与原子间的失谐量使光场的聚束效应与反聚束效应...  相似文献   

9.
以量子力学为基础对耦合场调控Λ型和V型联合原子系统中的吸收特性进行理论研究.针对弱探测场情况,采用微扰法求解系统密度矩阵运动方程,通过数值模拟得到系统的探测吸收谱.以耦合场2作为联结场,将耦合场1和耦合场2组成的V型系统以及耦合场2和探测场构成的Λ型系统联系在一起,通过调谐耦合场1的拉比强度控制EIT线宽和多窗口的变化,调谐耦合场2的频率失谐量控制EIT的非线性特性.  相似文献   

10.
本文将微扰展式方法用于研究非线性复合介质的传热情况.由于接触热阻的存在,势在两相界面上不再连续.研究表明,微扰展式方法也适用于研究相界面上势不连续的非线性系统.文中计算了含单个圆柱形杂质的复合介质的温度分布,并讨论了几种特殊情况.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

16.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

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