Theoretical analysis of the electromagnetic field inside an anomalous-dispersion microresonator under synthetical pump

We study the spatiotemporal evolution of the electromagnetic field inside a microresonator showing an anomalous dispersion at the pump wavelength by using the normalized Lugiato–Lefever equation. Unlike the traditional single continuous wave(CW) pumping, an additional pump source consisting of periodical pulse train with variable repetition rate is adopted.The influences of the microresonator properties and the pump parameters on the field evolution and the electromagnetic field profile are analyzed. The simulation results indicate that, in the anomalous dispersion regime, both increases of the input pulse amplitude and the repetition frequency can result in the field profiles consisting of multiple peaks. A series of equidistant pulses can also be obtained by increasing the CW pump power. In addition, we find that a large physical detuning between the pump laser carrier and the cavity resonance frequency also causes the splitting of the inside field.     

Exact analytical solutions to the mean-field model depicting microcavity containing semiconductor quantum wells

By using a two-mode mean-field approximation,we study the dynamics of the microcavities containing semiconductor quantum wells.The exact analytical solutions are obtained in this study.Based on these solutions,we show that the emission from the microcavity manifests periodic oscillation behaviour and the oscillation can be suppressed under a certain condition.     

超高Q值mm级晶体回音壁微腔加工

回音壁微腔具有超高Q值和极小的模式体积,在微波光子系统、非线性光学和量子光学等领域中具有广阔的应用前景。通过分析mm级氟化镁(MgF₂)晶体回音壁微腔的损耗因素,确认了影响回音壁微腔品质因数的主要指标为材料等级和表面粗糙度。设计了mm级MgF₂晶体回音壁微腔的结构形式,使用DUV级MgF₂晶体,如果回音壁微腔表面粗糙度小于0.7 nm,则MgF₂晶体回音壁微腔的极限损耗理论计算值为4.781×10^-11,对应的极限Q值为2.09×10¹⁰。通过对MgF₂晶体回音壁微腔进行粗成型、精密车削、精密抛光,实现了高品质因数的微腔制造。测试结果表明,回音壁微腔的表面粗糙度Ra值为0.669 nm、微观形貌PV值为6.767 nm、品质因数为2.054×10⁹@1 550 nm。     

四极子微腔的光场分布

应用电磁场理论和介质中的麦克斯韦方程组,推导了任意截面微腔的TM模光场分布。并以四极子状微腔截面为例,推导了含有传播常数的本征方程。用Mathematica软件模拟出具有不同变形因子的基模(m=1)和高阶模的光场分布图,得出基模在=45°,135°,225°,315°四个方向光辐射最强,具有“蝴蝶结模式”特征,并且当变形因子值取ε′为0.1~0.15时,该效应表现得更明显;而高阶模(m≥2)时微腔中没有这种光的定向输出现象,在任何变形因子情况下也不能形成稳定的“蝴蝶结模式”,为四极子微腔激光器的设计和制作提供了一定的理论依据。     

铌酸锂的耄耋之路:历史与若干进展

铌酸锂集压电、倍频、电光和光折变等特性于一身,被认为是非线性光学的模型晶体,已经表现出巨大的实用价值.铌酸锂在其诞生以来的近百年中,已经在国土安全、医学检测、高能物理、工业探测等领域占据着不可或缺的地位.随着微纳技术的发展,近年来铌酸锂微纳结构中新型光学效应的研究,已经成为国际上竞相争夺的前沿热点之一,相关研究对于产生...     

半导体微腔中激子的光学效应

文章基于Fabry-Pérot半导体微腔,阐述了新型元激发——激子极化激元的基本概念和微观描述,讨论了其在光学放大器、光学开关和单光子源方面的潜在应用,概述了对其实现Bose-Einstein凝聚的实验研究,最后对将来的发展做了一个简单的展望.     

Erbium‐doped integrated waveguide amplifiers and lasers

Erbium‐doped fiber devices have been extraordinarily successful due to their broad optical gain around 1.5–1.6 µm. Er‐doped fiber amplifiers enable efficient, stable amplification of high‐speed, wavelength‐division‐multiplexed signals, thus continue to dominate as part of the backbone of longhaul telecommunications networks. At the same time, Er‐doped fiber lasers see many applications in telecommunications as well as in biomedical and sensing environments. Over the last 20 years significant efforts have been made to bring these advantages to the chip level. Device integration decreases the overall size and cost and potentially allows for the combination of many functions on a single tiny chip. Besides technological issues connected to the shorter device lengths and correspondingly higher Er concentrations required for high gain, the choice of appropriate host material as well as many design issues come into play in such devices. In this contribution the important developments in the field of Er‐doped integrated waveguide amplifiers and lasers are reviewed and current and future potential applications are explored. The vision of integrating such Er‐doped gain devices with other, passive materials platforms, such as silicon photonics, is discussed.     

Entanglement concentration for an arbitrary hybrid less-entangled state and W state using quantum dots and a microcavity coupled system

We propose a practical entanglement concentration protocol(ECP) for a hybrid entangled state using quantum dots and a microcavity coupled system.A hybrid less-entangled state can be concentrated to a most-entangled state with a certain probability using only one ancillary single photon.Moreover,using this protocol,we can also concentrate an arbitrary three-particle less-entangled W state using two ancillary photons and classical communication.The proposed protocols provide us with a useful method to concentrate less-entangled states,which can be implemented with current technology.     

微盘腔垂直耦合器特性的拓展分析

利用垂直于微盘腔边界的波导与腔耦合是一种新开发的耦合技术. 采用有限元数值模拟方法对垂直耦合器的腔尺寸适应性、波长适应性和端口扩展性做出详细分析. 结果证实: 垂直耦合器在大尺寸腔中或者多个波段均有效; 并且多个垂直耦合器可以和同一盘腔交换能量, 实现滤波、分束、光路交叉的功能. 垂直耦合器在以微腔为元件的集成光路中的应用将使材料选取和光路排布更为灵活. 关键词： 微纳光学 微腔 回音壁模式 垂直耦合器     

Whispering gallery microcavity lasers

Whispering gallery mode (WGM) optical microresonators have attracted intense interests in the past decades. The combination of high quality factors (Q) and small mode volumes of modes in WGM resonators significantly enhances the light‐matter interactions, making them excellent cavities for achieving low threshold and narrow linewidth lasers. In this Review, the progress in WGM microcavity lasers is summarized, and the laser performance considering resonator geometries and materials as well as lasing mechanisms is discussed. Label‐free detection using WGM resonators has emerged as highly sensitive detection schemes. However, the resolution is mainly limited by the cavity Q factor which determines the mode linewidth. Microcavity lasers, due to their narrow laser spectral width, could greatly improve the detection resolution. Some recent developments in sensing using microcavity lasers are discussed.