首届全国量子声学讨论会在合肥召开

中国声学学会主办的首届全国量子声学讨论会于1985年6月22—25日在中国科技大学召开.与会代表32人,报告了学术论文28篇.中国声学学会副理事长魏荣爵教授、魏墨鑫教授出席了会议.在开幕式上魏荣爵教授作了题为“声学——从经典到量子、从线性到非线性”的综述报告.中国科技大学校长管维炎教授也参加了会议,并做了题为“声子——准粒子”的报告. 量子声学是声学领域中一个崭新的分支,是声学和凝聚态物理的交叉领域,具有旺盛的生命力.近年     

量子棒及其异质结的超低频拉曼光谱及有限元分析

硫族化镉纳米微晶由于具有发光效率高和发射波长可调谐等优良性质在光电器件中有重要的应用,CdSe/CdS点-棒异质结量子点是典型代表之一。本文中通过非共振拉曼方法探测了该量子点在5~50cm-1的声学声子模,利用不同模式的偏振特性,清晰地指认了球状核壳异质结量子点的扭转模式和径向呼吸模、棒状和点-棒异质结量子点的伸缩模和径向呼吸模等,并观察到了棒状量子点和点-棒异质结量子点的电子拉曼散射。同时发现点-棒异质结量子点的径向呼吸模较尺寸相当的纳米棒量子点发生红移。利用有限元方法形象模拟各量子点声学模的振动形式,并发现点-棒异质结量子点呼吸模振动的局域性。随后,引入局域有效声速的概念,利用改进的Lamb定律,成功解释了该红移是由CdSe核区域声速的减小所导致的,并再次验证该呼吸模局域在核附近区域。该研究对于表征和研究量子点中的限制性声学模具有重要意义,声学模和光学跃迁均局域在量子点附近区域的特性,对调控其激子-声子耦合和相关的光学性质具有重要指导意义。     

2004年全国物理声学学术会议在镇江召开

2004年全国物理声学学术交流会(第十届)于2004年10月22日至25日在江苏省镇江市召开。本届会议是由中国声学学会物理声学分会和江苏省声学学会物理声学专业委员会联合举办,由南京大学声学所和江苏大学承办。 本届会议的主题是"新世纪4年来声学各分支领域中物理声学研究的新进展"。会议收到论文65篇,其中大会综述报告2篇,非线性声学18篇,量子声学、声传播及其物理效应24篇,光声、热声和检测声     

含双T形量子结构的量子波导中声学声子输运和热导

采用散射矩阵方法, 研究了含双T形量子结构的量子波导中声学声子输运和热导性质. 结果表明: 在极低温度, 双T形量子结构能增强低温热导; 相反地, 在相对较高的温度范围, 双T形量子结构能降低低温热导. 而在整个低温范围内, 增加散射区域最窄处的宽度能增强低温热导. 计算结果表明可以通过调节含双T形量子结构的量子波导结构来调控声子的输运概率和热导. 关键词： 声学声子输运 热导 量子结构     

国内声学文献分类索引

国内声学文献分类索引庐学分类；４３．１０总类；４３．１５标准；４３．２０一般线性声学；４３．２５非线性声学；强声学；４３．２８航空声学；大气声学；４３．３０水声学；４３．３５超声学，量子声学及声的物理效应；４３．４０机械振动和冲击；４３．４５统计声学...     

国内声学文献分类索引

国内声学文献分类索引（声学分类：４３．１０总类；４３．１５标准；４３．２０一般线性声学；４３．２５非线性声学；强声学；４３．２８航空声学；大气声学；４３．３０水声学；４３．３５超声学，量子声学及声的物理效应；４３．４０机械振动和冲击；４３．４５统计声...     

国内声学文献分类索引

国内声学文献分类索引（声学分类：４３．１０总类；４３．１５标准；４３．２０一般线性声学；４３．２５非线性声学；强声学；４３．２８航空声学；大气声学；４３．３０水声学；４３．３５超声学，量子声学及声的物理效应；４３．４０机械振动和冲击；４３．４５统计声...     

国内声学文献分类索引

国内声学文献分类索引（声学分类：４３．１０总类；４３．１５标准；４３．２０一般线性声学；４３．２５非线性声学；强声学；４３．５８航空声学；大气声学；４３．３０水声学；４３．３５超声学，量子声学及声的物理效应；４３．４０机械振动和冲击；４３．４５统计声...     

2004年分类索引

(声学分类:43.1。总类;43.15标准;4320一般线性声学;43念5非线性声学;强声学;声学;4335超声学,量子声学及声的物理效应;43,40机械振动和冲击;43.45统计声学;学;4360声信号处理,声全息技术;43.63生理声学;43.66心理声学;43.70语言通信;43·85声学测量与仪器;43·88换能器;声音的     

国内声学文献分类索引

国内声学文献分类索引（声学分类：４３．１０总类；４３．１５标准；４３．２０一般线性声学；４３．２５非线性声学；强声学；４３．２８航空声学；大气声学；４３．３０水声学；４３．３５超声学，量子声学及声的物理效应；４３．４０机械振动和冲击；４３．４５统计声...     

C. V. Raman and Colonial Physics: Acoustics and the Quantum

Presenting the social and historical context of Chandrasekhara Venkata Raman, this paper clarifies the nature and development of his work in early twentieth-century colonial India. Raman’s early fascination with acoustics became the basis of his later insights into the nature of the light quantum. His work on light scattering played an important role in the experimental verification of quantum mechanics. In general, Raman’s worldview corrects certain Orientalist stereotypes about scientific practice in Asia.     

One-Dimensional Inverse Scattering Problem in Acoustics

We are concerned with the inverse scattering problem (ISP) in acoustics within the Marchenko inversion scheme. The quantum ISP is first discussed and applied in order to exhibit certain characteristics and application prospects of the method which could be useful in extending it to classical systems. We then consider the ISP in acoustics by assuming plane waves propagating in an elastic, isotropic, and linear medium. The wave equation is first transformed into a Schrödinger-like equation which can be brought into the Marchenko integral equation for the associated nonlocal kernel the solution of which provides us the full information of the underlying reflective profile. We apply the method in several model problems where the reflection coefficient of the multi-layer reflective medium is used as input to the ISP and in all cases we obtain excellent reproduction of the original structure of the scatterer. We then applied the inverse scattering scheme to construct profiles with certain predetermined reflection and transmission characteristics.     

全国声学标准化技术委员会的发展与国家声学基础测量方法标准体系建设

首先回顾了全国声学标准化技术委员会自1980年成立以来,在国家声学标准制、修订方面所取得的一批重要的标准研究成果。经过全国声学领域历届委员和专家30年来的共同努力,截止2009年共制、修订声学方面国家标准166项次,形成了目前归口声标委管理的131项现行有效的国家标准,由此也建立了涵盖声学基础、噪声、建筑声学、超水声四大类标准的国家声学基础测量方法标准体系。这些声学基础测量方法标准体系与国家声环境质量、噪声排放等环保标准和工程建设标准、电声和音视频等标准共同构成了较为完整的国家声学标准体系。最后结合声标委今后要开展的标准工作,提出了进一步完善国家声学基础测量方法标准体系的细部构想,可以相信,将来随着这些标准的陆续出台,我国声学标准体系会更趋完善。      

通信声学的发展及研究现状

人类作为信息交流的主要信息产生源和信息接收槽,语言声学、心理声学和生理声学在信息技术中发挥着越来越重要的作用。作为声学与信息技术相互渗透的产物-通信声学,近十几年来随着数字信号处理技术的发展,其研究和应用领域得到了很大的扩展。本文在简述通信声学产生和发展的必然性和必要性之后,主要介绍了通信声学目前的研究领域及其应用。     

New structures for closed-form wave solutions for the dynamical equations model related to the ion sound and Langmuir waves

This treatise analyzes the coupled nonlinear system of the model for the ion sound and Langmuir waves.The modified(G'/G)-expansion procedure is utilized to raise new closed-form wave solutions.Those solutions are investigated through hyperbolic,trigonometric and rational function.The graphical design makes the dynamics of the equations noticeable.It provides the mathematical foundation in diverse sectors of underwater acoustics,electromagnetic wave propagation,design of specific optoelectronic devices and physics quantum mechanics.Herein,we concluded that the studied approach is advanced,meaningful and significant in implementing many solutions of several nonlinear partial differential equations occurring in applied sciences.     

Phase-locking effects in a system of nonlinear oscillators

Models for the excitation of collective modes in a system of nonlinear classical oscillators, initially out of phase, are discussed. The oscillators may be coupled in a dissipative or conservative manner. The analysis is based on the results of recent studies dealing with the problem of the free excitation of a coherent pulse, analogous to "superradiance" in two-level quantum systems. Several physical examples from the realms of electrodynamics and acoustics are discussed. The processes discussed here may be thought of as chaos-order transitions, provided that "chaos" is understood not as a stochastic nature of an individual oscillator but as the absence of a coherent component in their collective field.     

Analogue Models of and for Gravity

Condensed matter systems, such as acoustics in flowing fluids, light in moving dielectrics, or quasiparticles in a moving superfluid, can be used to mimic aspects of general relativity. More precisely these systems (and others) provide experimentally accessible models of curved-space quantum field theory. As such they mimic kinematic aspects of general relativity, though typically they do not mimic the dynamics. Although these analogue models are thereby limited in their ability to duplicate all the effects of Einstein gravity they nevertheless are extremely important—they provide black hole analogues (some of which have already been seen experimentally) and lead to tests of basic principles of curved-space quantum field theory. Currently these tests are still in the realm of gedanken-experiments, but there are plausible candidate models that should lead to laboratory experiments in the not too distant future.     

Ultrasensitive optical measurement of thermal and quantum noises

We have developed an experiment of ultrasensitive interferometric measurement of small displacements based on a high-finesse Fabry-Perot cavity. We have observed the internal thermal noise of mirrors and fully characterized their acoustics modes with a sensitivity of 3 × 10⁻²⁰ m/Hz^1/2. This unique sensitivity is a step towards the first observation of the radiation pressure effects and the resulting standard quantum limit in interferometric measurements. Our experiment may become a powerful facility to test quantum noise reduction schemes such as the use of squeezed light or quantum locking of mirrors. As a first result, we present the observation of a cancellation of radiation pressure effects in our cavity. This back-action noise cancellation was first proposed within the framework of gravitational-wave detection with dual resonators, and may drastically improve the sensitivity of such measurements. The text was submitted by the authors in English.     

Strong and weak nonlinear dynamics: Models, classification, examples

The difference between strong and weak nonlinear systems is discussed. A classification of strong nonlinearities is given. It is based on the divergence or inanity of series expansions of the equation of state commonly used in the study of weak nonlinear phenomena. Such power or functional series cannot be used in three cases: (i) if the equation of state contains a singularity; (ii) if the series diverges for strong disturbances; (iii) if the linear term is absent, and higher nonlinearity dominates. Strong nonlinearities are known in acoustics, optics, mechanics and in quantum field theory. Mathematical models, solutions and observed phenomena are presented. For example, an equation of Heisenberg type and its generalization for strongly nonlinear wave system are given. In particular, exact solutions of new “quadratically cubic” Burgers and Riemann-Hopf equations are discovered.     

我国非线性声学方面的研究进展

轮廓地介绍了我国在非线性声学方面的研究状况和取得的成果,同时也概述了国外同行们的相应工作,对未来的工作提出了建议。