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模型子波处理技术在消除地震相位差异中的应用 被引量:5
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作者 于海铖 周小平 《油气地质与采收率》 CAS CSCD 北大核心 2010年第4期33-34,42,共3页
在地震资料处理过程中,由于受不同时期野外施工因素差异的影响,经反褶积后的地震子波存在一定的相位差,影响地震资料的拼接效果,而模型子波处理技术是一种估算和减少相位差异的新技术。该技术通过模型试算和实际地震资料的处理,可以消... 在地震资料处理过程中,由于受不同时期野外施工因素差异的影响,经反褶积后的地震子波存在一定的相位差,影响地震资料的拼接效果,而模型子波处理技术是一种估算和减少相位差异的新技术。该技术通过模型试算和实际地震资料的处理,可以消除不同震源、接收仪器引起的地震相位差异,提高地震资料品质与精度。通过对五号桩高精度三维地震资料和桩海大连片地震资料处理的实际应用,消除了不同类型检波器和不同震源导致的地震资料拼接处的相位差异,证明该处理技术非常有效。 展开更多
关键词 地震资料连片处理 相位差异 模型子波处理技术 反褶积 相位校正
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范氏气体下单空气枪震源子波模拟 被引量:6
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作者 王立明 许江 胡毅 《工程地球物理学报》 2017年第2期141-144,共4页
空气枪广泛应用于海洋地震勘探,但野外现场中震源子波的获取非常困难,条件也苛刻。因此利用空气枪震源子波模拟方法得到震源子波信号是一种行之有效的手段。以准静态开放式热力学系统与气泡振荡运动过程理论为基础,同时为了更符合空气... 空气枪广泛应用于海洋地震勘探,但野外现场中震源子波的获取非常困难,条件也苛刻。因此利用空气枪震源子波模拟方法得到震源子波信号是一种行之有效的手段。以准静态开放式热力学系统与气泡振荡运动过程理论为基础,同时为了更符合空气枪中的高压气体,引入了范氏气体,建立了单空气枪震源子波模型。通过震源子波模型模拟与实测子波数据对比表明,单空气枪震源子波模型模拟的结果与实测子波能较好的吻合,从而得出了该模型能准确模拟实测子波波形,而且操作上方便实用。 展开更多
关键词 空气枪 气泡振荡 范氏气体 子波模型
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气枪震源子波特征及应用研究 被引量:4
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作者 朱书阶 《勘探地球物理进展》 2008年第4期265-269,共5页
介绍了气枪震源激发的子波特征、选择沉枪深度的原则和各种气枪组合的原理。在经典自由气泡理论的基础上,对不同海域和不同海流流速条件下,气枪震源激发子波特征存在的差异,特别是初泡比相差很大的情况,作了较详尽的数学论证。引入流体... 介绍了气枪震源激发的子波特征、选择沉枪深度的原则和各种气枪组合的原理。在经典自由气泡理论的基础上,对不同海域和不同海流流速条件下,气枪震源激发子波特征存在的差异,特别是初泡比相差很大的情况,作了较详尽的数学论证。引入流体速度势概念,由伯努利方程推导出气泡外壁压强分布公式,探索性地提出:当沉枪较浅时,气泡震荡过程不仅取决于静水压强,而且与海流作用在气泡外壁的压强也息息相关。 展开更多
关键词 气枪子波 初泡比 子波理论模型 速度势函数 气泡震荡
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定量模拟分析船体与空气枪间的安全距离
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作者 王立明 胡毅 +1 位作者 许江 刘保华 《应用海洋学学报》 CSCD 北大核心 2016年第4期575-578,共4页
海洋地震勘探过程中,水中放置的空气枪与船体之间须保持一定安全距离,否则引起船载设施和仪器剧烈抖动,影响船舶设施和仪器的安全运行,甚至更严重情况下,有可能造成船体的损坏.利用海水压力脉冲与船体受到的冲击压力关系,结合建立的空... 海洋地震勘探过程中,水中放置的空气枪与船体之间须保持一定安全距离,否则引起船载设施和仪器剧烈抖动,影响船舶设施和仪器的安全运行,甚至更严重情况下,有可能造成船体的损坏.利用海水压力脉冲与船体受到的冲击压力关系,结合建立的空气枪震源子波模型模拟近场震源子波,可计算出船体与空气枪间的安全距离.研究结果表明,根据震源子波模型模拟的近场子波主峰值,总容量150in3G枪、300 in3相干G枪及760 in3相干G枪的安全距离分别为3.90、6.57 m和9.13 m.由此可知,空气枪与船体间距离只有大于安全距离,才能避免船体大的振动或设备免遭损害,保证海洋地震勘探有效、安全的进行. 展开更多
关键词 海洋地质学 空气枪 安全距离 子波模型 近场震源子波
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油气晕识别的滑动关联滤波法
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作者 周梅春 《物探化探计算技术》 CAS CSCD 1997年第4期343-347,共5页
本文以灰色系统理论为基础,将灰色关联度分析和滤波方法相结合,通过有效地选取已知子波模型,结合地质背景,在测区进行滑动关联滤波分析,达到较好地识别油气晕的目的。并附有C程序,实验的结果证实了该方法的可行性,对油气化探的... 本文以灰色系统理论为基础,将灰色关联度分析和滤波方法相结合,通过有效地选取已知子波模型,结合地质背景,在测区进行滑动关联滤波分析,达到较好地识别油气晕的目的。并附有C程序,实验的结果证实了该方法的可行性,对油气化探的数据处理具有参考价值。 展开更多
关键词 灰色系统 子波模型 滑动关联度滤波 油气晕
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Suppression of Speckle in SAR Images Using Wavelet-Based HMM
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作者 张志明 王越 +1 位作者 陶然 周思永 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期86-92,共7页
In order to suppress the speckle appearing in synthesis aperture radar (SAR) images, a novel speckle reduction method based on wavelet domain hidden Markov tree (HMT) was proposed. First, the image was logarithmic tra... In order to suppress the speckle appearing in synthesis aperture radar (SAR) images, a novel speckle reduction method based on wavelet domain hidden Markov tree (HMT) was proposed. First, the image was logarithmic transformed to change the statistical property of the speckles. Then an HMT was constructed in the correspondent wavelet domain. Based on this model, the image signal was restored by maximum likelihood estimation and speckle noise was suppressed. Simulating SAR images had shown that the performance of the filter is satisfactory for both speckle smoothing and edges presentation, and for generating visually natural images as well. 展开更多
关键词 synthetic aperture radar (SAR) WAVELET hidden Markov model(HMM) noise suppression image processing
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INFLUENCE OF VIRTUAL PHOTON FIELD ON COLLAPSE AND REVIVAL PHENOMENON IN TWO PHOTON J C MODEL WITHOUT RWA
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作者 杨雁南 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第1期86-92,共7页
The time evolution of system in two photon Jaynes Cummings (J C) model without rotating waves approximation (RWA) is obtained by using the theory of ordinary differential equations. Based on the evolution, the mean ... The time evolution of system in two photon Jaynes Cummings (J C) model without rotating waves approximation (RWA) is obtained by using the theory of ordinary differential equations. Based on the evolution, the mean value of the atom inversion operator 〈 S 3(t)〉 is gi ven. The influence of the “counter rotating term” on the collapse and revival phenomenon is discussed from the comparison between the cases with RWA and without RWA. It shows that the influence of the virtual photon field makes the quantum fluctuations appear on the collapse and revival phenomenon. 展开更多
关键词 PHOTONS quantum noise J C model rotating waves approximation collapse and revival phenomenon atom inversion operator
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Probabilistic Tracking of Objects with Adaptive Cue Fusion Mechanism 被引量:1
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作者 张波 田蔚风 金志华 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第2期185-189,共5页
A tracking method based on adaptive multiple cue fusion mechanism was presented,where particle filter is used to integrate color and edge cues.The fusion mechanism assigns different weights to two cues according to th... A tracking method based on adaptive multiple cue fusion mechanism was presented,where particle filter is used to integrate color and edge cues.The fusion mechanism assigns different weights to two cues according to their importance,thus improving the robustness and reliability of the tracking algorithm.Moreover,a multi-part color model is also invoked to deal with the confliction among similar objects.The experimental results on two real image sequences show the tracking algorithm with adaptive fusion mechanism performs well in the presence of complex scenarios such as head rotation,scale change and multiple person occlusions. 展开更多
关键词 multiple cue fusion particle filter multi-part color model
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Ground State Meson Spectrum in a Relativistic Model with Instanton Induced Interaction 被引量:1
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作者 Antony Prakash Monteiro K.B.Vijaya Kumar 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第2期325-330,共6页
The mass spectrum of the S-wave mesons is considered in the frame work of relativistic harmonic model (RHM). The full Hamiltonian used in the investigation has the Lorentz scalar plus a vector harmonic-oscillator po... The mass spectrum of the S-wave mesons is considered in the frame work of relativistic harmonic model (RHM). The full Hamiltonian used in the investigation has the Lorentz scalar plus a vector harmonic-oscillator potential, the confined-one-gluon-exchange potential (COGEP) and the instanton-induced quark-antiquak interaction (Ⅲ). A good description of the mass spectrum is obtained. The respective role of Ⅲ and COGEP in the S-wave meson spectrum is discussed. 展开更多
关键词 quark model confined-one-gluon-exchange potential instanton induced interaction S-wave spectra
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Evolution of Bond-Order-Wave Phase in One-Dimensional Mott Insulators 被引量:3
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作者 HUANG Xiao-Xuan PAN Zheng-Quan +2 位作者 XU Zhao-Xin DAI Jian-Hui YING He-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期923-928,共6页
In this paper, by using the level spectroscopy method and bosonization theory, we discuss the evolution of the bond-order-wave (BOW) phase in a one-dimensional half-filled extended Hubbard model wlth the on-site Cou... In this paper, by using the level spectroscopy method and bosonization theory, we discuss the evolution of the bond-order-wave (BOW) phase in a one-dimensional half-filled extended Hubbard model wlth the on-site Coulomb repulsion U as well as the inter-site Coulomb repulsion V and antiferromagnetic exchange J. After clarifying the generic phase diagrams in three limiting cases with one of the parameters being fixed at zero individually, we find that the BOW phase in the U-V phase diagram is initially enlarged as J increases from zero but is eventually suppressed as J increases further in the strong-coupling regime. A three-dimensional phase diagram is suggested where the BOW phase exists in an extended region separated from the spin-density-wave and charge-density-wave phases. 展开更多
关键词 bond-order-wave phase Mott insulators one-dimensional extended Hubbard model
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Correction of the Littlest Higgs Model to Higgs Production Process e-γ→veW-H in e-γ Collisions 被引量:1
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作者 LIU Yao-Bei DU Lin-Lin WANG Xue-Lei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第4X期699-704,共6页
The littlest Higgs model is the most economical one among various little Higgs models. In the context of the littlest Higgs (LH) model, we study the process e-γ → veW^-H and calculate the contributions of the LH m... The littlest Higgs model is the most economical one among various little Higgs models. In the context of the littlest Higgs (LH) model, we study the process e-γ → veW^-H and calculate the contributions of the LH model to the cross section of this process. The results show that in most of the parameter spaces preferred by the electroweak precision data, the value of the relative correction is larger than 10%. Such correction to the process e-γ →veW^-H is large enough to be detected via e-γ collisions in the future high energy linear e^+ e^- collider (ILC) experiment with the c.m. energy √s = 500 GeV and a yearly integrated luminosity £ = 100fb^-1, which will give an idea/way to test the model. 展开更多
关键词 littlest Higgs model Higgs boson cross section
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Electrostatic Waves in Weakly Magnetized Quantum Plasmas
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作者 王春华 孙晓霞 王超群 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第4期771-772,共2页
By using the quantum magnetohydrodynamic model, the electrostatic waves in weakly magnetized quantum plasmas are investigated. The electrons are treated as a quantum and magnetized species, while the ions are classica... By using the quantum magnetohydrodynamic model, the electrostatic waves in weakly magnetized quantum plasmas are investigated. The electrons are treated as a quantum and magnetized species, while the ions are classical unmagnetized ones. The general dispersion relations are derived. It is shown that, both the high frequency electron waves (Langmuire wave and upper-hybrid wave) and the low frequency ion acoustic wave can propagate when the plasmas are cold. 展开更多
关键词 electrostatic wave quantum plasma weakly magnetized
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Unscented Particle Filter Algorithm for Ballistic Target Tracking 被引量:1
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作者 ZHAI Yan GUO Xiaobo YAN Yonggang 《International Journal of Technology Management》 2014年第8期122-124,共3页
At present, the ballistic Target tracking has a higher demand in convergence rate and tracking precision of filter algorithm. In the paper, a filter algorithm was improved based on particle filter. The algorithm was c... At present, the ballistic Target tracking has a higher demand in convergence rate and tracking precision of filter algorithm. In the paper, a filter algorithm was improved based on particle filter. The algorithm was carried out from the aspects such as particle degradation and particle diversity lack. A novel ballistic coefficient parameter model was built, and was expanded to the state vector for filtering. Finally, the improved algorithm was simulated by MATLAB software. The simulation results show that the algorithm can obtain better convergence speed and tracking precision. 展开更多
关键词 Unscented particle filter reentry target ballistic target tracking filtering.
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Solitary Excitations of Dipolar Bosons in Optical Lattice under Magnetic Fields
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作者 WANG Shi-En 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2X期233-238,共6页
We obtain the multisolitary solutions of the extended Bose-Hubbard model which describes dipolar Bose- Einstein condensates in optical lattices under time-dependent magnetic fields, and indicate that the nonlinearity ... We obtain the multisolitary solutions of the extended Bose-Hubbard model which describes dipolar Bose- Einstein condensates in optical lattices under time-dependent magnetic fields, and indicate that the nonlinearity is due to both on-site short-range interactions and also (long-range) dipole-dipole interactions which can act between neighboring sites. The discrete breathers as nonlinear excitations are always oscillatory in time and can also be spatially localized, while the oscillatory frequencies are determined by an external field. We show that these excitations will be observable and discuss how the parameters can be tuned in future experiments. 展开更多
关键词 solitary excitation extended Bose-Hubbard model BOSONS optical lattice
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ONCOGENIC TRANSFORMATION OF SYRIAN HAMSTER EMBRYO CELLS BY 5.3-MeV α PARTICLES AND A TUMOR PROMOTER PHORBOL ESTER  被引量:1
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作者 寿江 龚诒芬 吴德昌 《Chinese Medical Sciences Journal》 CAS CSCD 1996年第4期195-199,共5页
The primary Syrian hamster embryo(SHE) cells were used to study the oncogenic transformation by  ̄(238)pu α particles or X-rays alone or in combination with a chemical promoter phorbol ester.Survival curves of SHE ce... The primary Syrian hamster embryo(SHE) cells were used to study the oncogenic transformation by  ̄(238)pu α particles or X-rays alone or in combination with a chemical promoter phorbol ester.Survival curves of SHE cells following exposure to α-particles or X-rays were fitted to single-or multi-target models,respectively. Model parameters were: Do = 0. 55 Gy. n = 1 for α particles 4 Do = 1.44 Gy. Dq = 3.0 Gy. n=7.7 for X-rays.Incidence of α particles or X-rays induced cell transformation was dose-dependant.α particles were more efficient in inducing cell transformation than that of X-rays. The enhancement of SHE cell transformation by phorbol 12-myristate 13-acetate(PMA) following exposure to α particles of 0. 25-1. 00 Gy was observed. 展开更多
关键词 oncogenic transformation syrian hamster embryo cells α particles
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A Robust Interacting Multisensor State Fusion Based on Adaptive Outlier Controlling Multirate Model
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作者 牛沿茏 李建勋 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第5期577-583,共7页
An adaptive outlier controlling multirate model based on Hong’s multirate kinetic model was represented in order to resist the outliers and utilize their useful information. Wavelet transform was introduced to detect... An adaptive outlier controlling multirate model based on Hong’s multirate kinetic model was represented in order to resist the outliers and utilize their useful information. Wavelet transform was introduced to detect and control the outliers. The multirate information extraction and the controlling of outliers were properly integrated to establish an adaptive outlier controlling multirate model. The proposed model was applied to multisensor state fusion with interacting multiple model (IMM), and a robust interacting multisensor state fusion algorithm was established based on adaptive outlier controlling multirate model. The Monte-Carlo simulation shows that it could improve the accuracy of fusion estimation by 70% compared to Hong’s algorithm and at least 14% to Xiao’s algorithm. 展开更多
关键词 adaptive outlier controlling wavelet transform multirate model state fusion
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A novel maneuvering multi-target tracking algorithm based on multiple model particle filter in clutters 被引量:2
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作者 胡振涛 Pan Quan Yang Feng 《High Technology Letters》 EI CAS 2011年第1期19-24,共6页
To solve the problem of strong nonlinear and motion model switching of maneuvering target tracking system in clutter environment, a novel maneuvering multi-target tracking algorithm based on multiple model particle fi... To solve the problem of strong nonlinear and motion model switching of maneuvering target tracking system in clutter environment, a novel maneuvering multi-target tracking algorithm based on multiple model particle filter is presented in this paper. The algorithm realizes dynamic combination of multiple model particle filter and joint probabilistic data association algorithm. The rapid expan- sion of computational complexity, caused by the simple combination of the interacting multiple model algorithm and particle filter is solved by introducing model information into the sampling process of particle state, and the effective validation and utilization of echo is accomplished by the joint proba- bilistic data association algorithm. The concrete steps of the algorithm are given, and the theory analysis and simulation results show the validity of the method. 展开更多
关键词 maneuvering multi-target tracking multiple model particle filter interacting multiple model IMM) joint probabilistic data association
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GI枪结构震源子波模拟研究 被引量:3
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作者 王立明 胡毅 +2 位作者 王瑜 刘保华 许江 《地球物理学进展》 CSCD 北大核心 2015年第6期2793-2796,共4页
GI枪不同于常规空气枪,它虽然使子波峰-峰值减少,但是具有较好的压制气泡振荡的优点.现在GI枪已经成为海上地震勘探主要震源激发方式之一.因此研究GI枪子波特性和模拟子波过程就有理论与现实意义.GI枪震源子波模型是依据GI枪激发特性,... GI枪不同于常规空气枪,它虽然使子波峰-峰值减少,但是具有较好的压制气泡振荡的优点.现在GI枪已经成为海上地震勘探主要震源激发方式之一.因此研究GI枪子波特性和模拟子波过程就有理论与现实意义.GI枪震源子波模型是依据GI枪激发特性,基于空气枪震源子波模型理论,以准静态开放式热力学系统与气泡振荡方程为依托建立的.模型根据模拟经验参数模拟震源子波结果,并与GI枪实测子波资料进行了对比,模拟结果表明能较好的吻合.文中同时给出子波模拟经验参数,使模型标准化. 展开更多
关键词 GI枪 气泡振荡 模拟子波 子波模型 标准化
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A COMPRESSION ALGORITHM FOR ECG BASED ON INTEGER LIFTING SCHEME WAVELET TRANSFORM
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作者 Zhang Kunyan Guo Yinjing Lü Wenhong Sun Jinping Wang Xiuzhen 《Journal of Electronics(China)》 2007年第5期674-678,共5页
In view of the shortcomes of conventional ElectroCardioGram (ECG) compression algo- rithms,such as high complexity of operation and distortion of reconstructed signal,a new ECG compression encoding algorithm based on ... In view of the shortcomes of conventional ElectroCardioGram (ECG) compression algo- rithms,such as high complexity of operation and distortion of reconstructed signal,a new ECG compression encoding algorithm based on Set Partitioning In Hierarchical Trees (SPIHT) is brought out after studying the integer lifting scheme wavelet transform in detail.The proposed algorithm modifies zero-tree structure of SPIHT,establishes single dimensional wavelet coefficient tree of ECG signals and enhances the efficiency of SPIHT-encoding by distributing bits rationally,improving zero-tree set and ameliorating classifying method.For this improved algorithm,floating-point com- putation and storage are left out of consideration and it is easy to be implemented by hardware and software.Experimental results prove that the new algorithm has admirable features of low complexity, high speed and good performance in signal reconstruction.High compression ratio is obtained with high signal fidelity as well. 展开更多
关键词 Electro Cardio Gram (ECG) Integer lifting scheme Wavelet transform Set Partitioning InHierarchical Trees (SPIHT)
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Cavity-Enhanced Third Harmonic Generation
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作者 YANGXiao-Xue WUYing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期318-320,共3页
We derive the analytical expression of microcavity-enhanced factor for third harmonic generation in terms of detunings, linewidths, and the Purcell factors of the relevant microcavity modes. It is suitable for microca... We derive the analytical expression of microcavity-enhanced factor for third harmonic generation in terms of detunings, linewidths, and the Purcell factors of the relevant microcavity modes. It is suitable for microcavities with any dimensions and arbitrary geometric shapes. 展开更多
关键词 MICROCAVITIES third harmonic generation quantum optics multi-wave mixing
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