Towards 1000-mode Optical Fibres

土壤温度对密集波分复用光纤链路单向光频传输的影响

Effect of soil temperature on one-way optical frequency transfer through dense-wavelength-division-multiplexing fibre links

本文给出了在载波级密集波分复用（DWDM）光纤网络上进行光频传输的结果。土壤温度变化之间的关系埋在光纤和频率变化的光载波通过光纤建模。土壤温度，测量在不同的深度由荷兰皇家气象研究所（KNMI）进行了比较，通过这个模型观察到的频率变化。通过2x298公里光纤链路的9天光频测量记录与土壤温度数据的比较显示出定性一致。土壤温度模型用于预测较长时期（天-月-年）的链路稳定性。我们表明，单向光频率传播是足够稳定的分布和比较，例如铷频率标准在标准的DWDM光纤网络。

空芯光纤中的光孤子

Optical Solitons in Hollow-Core Fibres

本文回顾了充气空芯光纤中光孤子动力学的研究，涵盖不同光纤结构对孤子传输、自压缩、自频移和色散波发射的影响，展示了从兆瓦到太瓦功率、亚飞秒脉宽及跨紫外到近红外的可调谐脉冲产生。

用于量子应用的微结构光纤：展望

Microstructured optical fibres for quantum applications: perspective

本文综述了微结构光纤在量子技术中的最新进展，指出实心和空芯光纤的光学非线性可用于量子资源态生成与频率转换，且空芯光纤凭借低损耗、低延迟和低色散在量子网络链路及原子实验中具有巨大潜力。

Step-index optical fibre drawn from 3D printed preforms

Optical fibre is drawn from a dual-head 3D printer fabricated preform made of two optically transparent plastics with a high index core (NA ~ 0.25, V > 60). The asymmetry observed in the fibre arises from asymmetry in the 3D printing process. The highly multi-mode optical fibre has losses measured by cut-back as low as α ~ 0.44 dB/cm in the near IR.

光学吸收光谱揭示了反谐振空芯光纤中的气态氯

Optical absorption spectrum reveals gaseous chlorine in anti-resonant hollow core fibres

本研究发现新拉制空芯光纤中紫外光的意外光谱衰减源于气态氯吸收，敞开光纤两端后该损耗随时间消散，透射光谱最终恢复正常。

掺铒光纤预制棒中磷酸盐结晶的光谱特征

Spectroscopic signature of phosphate crystallization in Erbium-doped optical fibre preforms

在稀土掺杂石英光纤中，放大离子的均匀分布及其部分光谱特性通常通过添加选定的元素（例如磷或铝）作为结构改性剂来改善。在掺铒光纤中，磷离子优先与铒离子配位，形成规则的笼状结构，但文献中所描述的晶体结构从未给出特殊的光谱特征。本文报道了掺磷透明石英光纤预制棒中Er ~（3+）的发射和激发光谱。在室温和低温下观察到的线特征归因于ErPO 4微晶。

二氧化硅基光纤中的掺铒纳米颗粒

Erbium-doped nanoparticles in silica-based optical fibres

开发用于功率放大器和激光器的新型稀土（RE）掺杂光纤需要不断改进光纤光谱特性（如增益曲线的形状和宽度、光量子效率、抗光谱烧孔和光暗化.）。二氧化硅玻璃作为纤维的基质材料已被证明是非常有吸引力的。然而，当掺杂到二氧化硅中时，RE掺杂光纤的一些潜在应用在光谱特性方面受到限制，这是由于成簇或不适当的局部环境造成的。为此，我们提出了一种新的路线来修改一些光谱性质的稀土离子在硅基纤维的基础上，铒离子在非晶介电纳米粒子的掺入，原位生长在纤维预制件。通过将低浓度的碱土元素添加到二氧化硅中，可以获得具有不可渗透间隙的玻璃。然后，在适当的热处理下发生相分离。我们研究了三种碱土元素：镁、钙和锶的作用。我们提出了实现稳定的纳米铒掺杂的介电纳米粒子内的二氧化硅纤维的核心。我们提出了纳米粒子的尺寸表征纤维样品。我们还显示了不同成分的预制棒和光纤样品中铒的光谱特性。这条新的路线在改进掺稀土光纤放大器和激光光源方面具有重要的潜力。

光纤中的空分复用技术

Space Division Multiplexing in Optical Fibres

几十年来，光通信技术取得了巨大而稳定的进步，为我们日益信息化的社会和经济提供了关键资源。这些进展主要是在寻找创新方法来增加单根光纤的数据承载能力。在这项研究中，研究人员探索了（并接近最大限度地利用）每一个可用的自由度，甚至商业系统现在也利用时间，波长，偏振和相位的多路复用来加速光纤基础设施中的更多信息。显然，在这些系统中，一个潜在的巨大改进来源尚未开发：光纤可以轻松地支持数百种空间模式，但今天的商业系统（单模或多模）没有尝试将这些用作独立信号的并行通道。

用MCVD制备大模场面积泄漏光纤

Large-mode-area leaky optical fibre fabricated by MCVD

采用MCVD工艺制备了一种基于漏模滤波的大模场面积单模光纤。包层结构将基模与高阶模区分开。初步版本具有25- $μ$ m芯直径和0.11数值孔径。一个高斯型模式与22- $μ$ m MFD观察后3米传播，与建模。

Dispersion map induced energy transfer between solitons in optical fibres

We propose an experimental setup to study collision-induced soliton amplification. In an optical fibre with anomalous dispersion ($β_2 < 0$), we replace a small region of the fibre with a normal dispersion fibre ($β_2 > 0$). We show that solitons colliding in this region are able to exchange energy. Depending on the relative phase of the soliton pair, we find that the energy transfer can lead to an energy gain in excess of $20\%$ for each collision. A sequence of such events can be used to enhance the energy gain even further, allowing the possibility of considerable soliton amplification. Thi…

Proca Fields in Step-index Optical Fibres

The topic of a photon mass has received justified attention over the years with strong theoretical reasoning for its existence. We derive a full description of mode solutions in step-index optical fibres on the basis of Proca's equation as a model for massive photons. The no-go theorem recently found in coaxial waveguides does not appear in the optical fibre case.

Giving light a new twist with standard optical fibres: rainbow Archimedean spiral emission

We demonstrate a new practical approach for generating multicolour spiral-shaped beams. It makes use of a standard silica optical fibre, combined with a titled input laser beam. The resulting breaking of the fibre axial symmetry leads to the propagation of a helical beam. The associated output far-field has spiral shape, independently of the input laser power value. Whereas, with a high-power near-infrared femtosecond laser, a visible supercontinuum spiral emission is generated. With appropriate control of the input laser coupling conditions, the colours of the spiral spatially self-organize i…

光在直光纤和弯曲光纤中的接收和传播的计算研究

Computational studies of light acceptance and propagation in straight and curved optical fibres

本文用蒙特卡罗模拟方法模拟了光线光学在圆柱形光纤中的跟踪。计算了有源光纤中斜光线和经向光线的捕获效率以及所有捕获光线的特征量分布。该模拟为弯曲纤维提供了新的结果，其中解析表达式太复杂而无法求解。由于光纤的急剧弯曲的光损耗作为一个函数的曲率比光纤半径和弯曲角。结果表明，当曲率半径曲率半径与纤维半径之比大于65时，损耗小于10%，且损耗发生在弯曲的初始阶段（弯曲角φ约为π/8 rad）。

用于光放大器的同轴双芯谐振泄漏光纤

Co-axial dual-core resonant leaky fibre for optical amplifiers

我们提出了一种同轴双芯谐振泄漏光纤的设计，其中的外芯是高度泄漏。一个合适的参数选择可以使我们能够谐振耦合功率从内核到外核。在大芯光纤中，这样的谐振耦合可以显著增加基模和高阶模之间的差分泄漏损耗，并且可以导致有效的单模操作。在小芯单模光纤中，这种耦合可以导致谐振波长附近的波长相关泄漏损耗的急剧增加，并且可以用于抑制放大的自发发射，从而实现光放大器的增益均衡。我们研究了光纤的传输特性，使用传输矩阵法，并提出了一个例子，大模式面积设计高功率放大器和波长可调的泄漏损耗设计的光放大器的固有增益均衡。

Silicon photonic-electronic neural network for fibre nonlinearity compensation

In optical communication systems, fibre nonlinearity is the major obstacle in increasing the transmission capacity. Typically, digital signal processing techniques and hardware are used to deal with optical communication signals, but increasing speed and computational complexity create challenges for such approaches. Highly parallel, ultrafast neural networks using photonic devices have the potential to ease the requirements placed on the digital signal processing circuits by processing the optical signals in the analogue domain. Here we report a silicon photonice-lectronic neural network for …

Modelling self-similar parabolic pulses in optical fibres with a neural network

We expand our previous analysis of nonlinear pulse shaping in optical fibres using machine learning [Opt. Laser Technol., 131 (2020) 106439] to the case of pulse propagation in the presence of gain/loss, with a special focus on the generation of self-similar parabolic pulses. We use a supervised feedforward neural network paradigm to solve the direct and inverse problems relating to the pulse shaping, bypassing the need for direct numerical solution of the governing propagation model.

Air-structured optical fibre drawn from a 3D-printed preform

A structured optical fibre is drawn from a 3D-printed structured preform. Preforms containing a single ring of holes around the core are fabricated using filament made from a modified butadiene polymer. More broadly, 3D printers capable of processing soft glasses, silica and other materials are likely to come on line in the not-so distant future. 3D printing of optical preforms signals a new milestone in optical fibre manufacture.

All-optical switching based on soliton self-trapping in dual-core high-contrast optical fibre

A systematic numerical study of ultrafast nonlinear directional coupler performance based on soliton self-trapping in a novel type of dual-core optical fibre is presented. The considered highly nonlinear fibre structure is composed of a real, intentionally developed soft glass-pair with high refractive index contrast at the level of 0.4 in the near infrared. Nonlinear propagation of picojoule level femtosecond pulses was studied numerically with the aim to identify the best switching performance in input parameter space of 1400 - 1800 nm in terms of excitation wavelengths, and of 75 - 150 fs i…

Quantum information processing with space-division multiplexing optical fibres

The optical fibre is an essential tool for our communication infrastructure since it is the main transmission channel for optical communications. The latest major advance in optical fibre technology is spatial division multiplexing (SDM), where new fibre designs and components establish multiple co-existing data channels based on light propagation over distinct transverse optical modes. Simultaneously, there have been many recent developments in the field of quantum information processing (QIP), with novel protocols and devices in areas such as computing, communication and metrology. Here, we …

Light transport and vortex-supported wave-guiding in micro-structured optical fibres

In hydrodynamics, vortex generation upon the transition from smooth laminar flows to turbulence is generally accompanied by increased dissipation. However, plane vortices can provide transport barriers and decrease losses, as it happens in numerous geophysical, astrophysical flows and in tokamaks. Photon interactions with matter can affectlight transportin waveguides in unexpected and somewhat counterintuitive ways resembling fluid dynamics. Here, we demonstrate dramatic impact of light vortex formation in micro-structured optical fibres on the energy dissipation. We show possibility of vortic…

光纤全光谱漫射和光束式太阳能应用

Full Spectrum Diffused and Beamed Solar Energy Application Using Optical Fibre

现有的太阳能应用系统使用全光谱太阳能的一小部分。因此，试图表明如何全光谱太阳能可以用于漫射和光束形式的入射太阳能。讨论了光纤散射太阳光的发光太阳聚光器（LSC）原理和光纤束式介质镜分离技术。对两种情况进行了比较。关键词：全光谱，太阳光子学，漫射太阳能，束流太阳能，LSC，介质镜，光纤，光伏

多层漏包层光纤的双折射分析

Birefringence analysis of multilayer leaky cladding optical fibre

本文用有限元法分析了多层漏包层（MLC）光纤，研究了MLC对两种结构的弯曲损耗和双折射的影响：（i）圆芯大模面积结构和（ii）椭圆小芯结构。在一个大的模式面积的结构中，我们验证了多层泄漏包层强烈歧视高阶模式，实现单模操作，光纤示出可忽略的双折射，和弯曲半径大于10厘米的光纤的弯曲损耗低。在椭圆小芯结构中，我们表明MLC降低了光纤的双折射。这防止了结构在任何偏离圆形几何形状的情况下变得双折射。这一研究结果对MLC光纤的高功率放大器、增益平坦化和色散补偿等方面的应用具有一定的指导意义。

可扩展的全光纤模式数据传输与保轮廓解码

Scalable All-Optical Fibre-Mode Data Transmission with Profiles-Preserved Decoding

提出一种基于微透镜阵列辅助解码架构的全光学保轮廓解码方法，通过通道相关球面相位补偿实现可扩展的高维光纤模式分离，实验验证了八模传输与语义信息恢复。

光纤宽带光隔离器

Broadband optical isolator in fibre optics

提出了一种宽带光二极管，它是由一个消色差的互易四分之一波片和一个非互易四分之一波片，都放置在两个交叉的偏振片之间。所提出的消色差波片的设计依赖于斯托克斯矢量的绝热演化，因此，该方案是鲁棒的和有效的。提出了利用纤维光学的可能的简单实现方法。

基于光纤的飞秒激光器的光学频率合成与测量

Optical frequency synthesis and measurement using fibre-based femtosecond lasers

我们报告了在1543 nm附近的电信窗口中的超精确和极其稳定的光频率的合成和测量。使用基于光纤的飞秒频率梳，我们已经将194 THz的光纤激光器相位稳定到344 THz的光学频率标准，从而将光学频率标准的特性转移到另一个光谱区域。相对于光频标，194 THz的合成频率被确定为在1 mHz以内，并且其分数频率不稳定性被测量为在1 s时小于2*10^{-15}，在8000 s后达到5*10^{-18}。我们还针对铯喷泉钟测量了合成频率：这里频率比较本身对不确定性的贡献小于4 mHz（2*10^{-17}）。我们的研究结果证实了基于光纤的频率梳技术的适用性，用于精确测量和频率合成，并通过使用光纤传输频率信息，使远距离比较的光学时钟。

微结构光纤模拟的“穷人方法”

A "poor man's approach" to modelling of micro-structured optical fibres

基于标量Helmholtz方程和有限差分近似，我们制定了一个矩阵本征值问题的计算，β（ω），在微结构光纤中的传播常数。该方法适用于指数引导光纤以及空芯光子带隙光纤，并在这两种情况下定性正确的结果found.Strength这种方法在于它非常简单的数值实现和它的能力，找到本征模在一个特定的本征值，这是非常感兴趣的，在光子带隙光纤中的缺陷模式建模时。

由新型亚微秒响应时间光纤传感控制设备赋能的实时光网络传感控制平面

Real-time Optical Network Sensing Control Plane Enabled by a Novel Sub us Response Time Fibre Sensing Control Device

本研究提出并实现了新型光纤传感控制设备及配套传感控制平面，可有效管控基于后向散射与偏振的光纤传感，经光纤网络实验验证其能达到亚微秒级响应时间，为实时光网络传感提供支撑。

Laser Nano-Filament Explosion for Enabling Open-Grating Sensing in Optical Fibre

Embedding strong photonic stopbands into traditional optical fibre that can directly access and sense the outside environment is challenging, relying on tedious nanoprocessing steps that result in fragile thinned fibre. Ultrashort pulsed laser filaments have recently provided a non contact means of opening high aspect ratio nanoholes inside of bulk transparent glasses. This method has been extended here to optical fibre, resulting in high density arrays of laser filamented holes penetrating transversely through the silica cladding and guiding core to provide high refractive index contrast Brag…

用于光纤激光源的掺杂与结构化二氧化硅光纤

Doped and structured silica optical fibres for fibre laser sources

本文研究在光纤纤芯中对Er3+和Yb3+离子进行微纳结构化，突破传统共掺光纤仅能实现1550 nm单波长发射的限制，演示了1042 nm与1550 nm双波长可控激光输出，为多波长有源光纤制造提供新途径。

Alignment of Free-Space Coupling of Few-Mode Fibre to Multi-Mode Fibre using Digital Holography

Off-axis digital holography is used to align a few-mode fiber to a multi-mode fiber in a free-space optical setup. Alignment based on power coupling measurements alone cannot guarantee low mode-dependent loss. The proposed alignment method enables reliable fiber coupling with low mode-dependent loss and crosstalk.

Ballistic and snake photon imaging for locating optical endomicroscopy fibres

We demonstrate determination of the location of the distal-end of a fibre-optic device deep in tissue through the imaging of ballistic and snake photons using a time resolved single-photon detector array. The fibre was imaged with centimetre resolution, within clinically relevant settings and models. This technique can overcome the limitations imposed by tissue scattering in optically determining the in vivo location of fibre-optic medical instruments.

Characteristics and stability of soliton crystals in optical fibres for the purpose of optical frequency comb generation

We study the properties of a soliton crystal, an bound state of several optical pulses that propagate with a fixed temporal separation through the optical fibres of the proposed approach for generation of optical frequency combs (OFC) for astronomical spectrograph calibration. This approach - also being suitable for subpicosecond pulse generation for other applications - consists of a conventional single-mode fibre and a suitably pumped Erbium-doped fibre. Two continuous-wave lasers are used as light source. The soliton crystal arises out of the initial deeply modulated laser field at low inpu…

用于光纤数据恢复的非线性集成光学谐振器

Nonlinear integrated optical resonators for optical fibre data recovery

该研究在仿真中采用基于倏逝耦合 GaAs 微环的储备池计算机，实时补偿高速光纤通信中的非线性失真，并在 20 km、12 dBm 条件下使 50 Gbaud 16-QAM 信号误码率低于 FEC 门限。

多模光纤中模式分解的新方法

New methods for modal decomposition in multi-mode fibres

本文提出并演示了两种用于多模光纤中模式分解的新方法，分别改进了光谱和空间成像技术并提出了适用于任意光纤的更简单快速的表征方案，成功验证了多种光纤。

Temporal Fresnel diffraction induced by phase jumps in linear and nonlinear optical fibres

We analytically and numerically study the temporal intensity pattern emerging from the linear or nonlinear evolutions of a single or double phase jump in an optical fiber. The results are interpreted in terms of interferences of the well-known diffractive patterns of a straight edge, strip and slit and a complete analytical framework is provided in terms of Fresnel integrals for the case of purely dispersive evolution. When Kerr nonlinearity affects the propagation, various coherent nonlinear structures emerge according to the regime of dispersion.

Deep Learning Cell Imaging through Anderson Localizing Optical Fibre

We demonstrate a deep-learning-based fibre imaging system which can transfer real-time artifact-free cell images through a meter-long Anderson localizing optical fibre. The cell samples are illuminated by an incoherent LED light source. A deep convolutional neural network is applied to the image reconstruction process. The network training uses data generated by a set-up with straight fibre at room temperature (~20 °C) but can be utilized directly for high fidelity reconstruction of cell images that are transported through fibre with a few degrees bend and/or fibre with segments heated up to 5…

Frequency stability and phase noise measurements of a 5,860 km-long intercontinental seafloor optical fibre cable

Optical clock comparison via optical fibre links has been achieved over continental scales, but has not yet been demonstrated intercontinentally. The transfer of ultra-stable optical frequencies over transoceanic distances is a challenging task, as the seafloor cable architecture prevents the use of environmental noise suppression techniques currently employed on land-based metrological links. As a fundamental first step towards devising suitable frequency transfer techniques to enable future clock comparison on a global scale, here we show the free-running frequency stability and phase noise …

布里渊放大支持1400~km地下光纤光频传输的$1\times10^{-20}$精度

Brillouin amplification supports $1\times10^{-20}$ accuracy in optical frequency transfer over 1400~km of underground fibre

我们研究了连接布伦瑞克和斯特拉斯堡的1400~km地下光纤环路上的光频率传输。大型自主光纤布里渊放大器（FBA）是中间放大的唯一手段，允许长达数天的相位连续测量。在大约三周的测量周期内，我们发现传输频率的分数偏移的加权平均值为$(1.1\pm0.4)\times10^{-20}$。在最好的情况下，我们发现$6.9\times10^{-21}$的不稳定性和$4.4\times10^{-21}$的分数频率偏移在平均时间约为30~000~s。这些结果代表了一个上限，可实现的不确定性超过1400公里时，使用一个链的远程布里渊放大器，并允许我们调查系统的影响，在$10^{-20}$水平。

碘在空芯光纤中的饱和光谱

Saturation Spectroscopy of Iodine in Hollow-core Optical Fibre

我们提出了高分辨率的光谱碘蒸气，是加载和捕获内的空芯光子晶体光纤（HC-PCF）的核心。我们比较所观察到的光谱特征，在传统的碘细胞中看到的，并表明饱和特性显着不同。尽管受限的几何形状，仍然可以获得具有非常高对比度的~6 MHz频谱宽度的亚多普勒特征。我们提供了一个简单的理论，它能精确地再现实验中的所有关键观察结果。

用于宽带量子存储器的空芯光子晶体光纤中的高效光泵浦和高光学深度

Efficient optical pumping and high optical depth in a hollow-core photonic-crystal fibre for a broadband quantum memory

大的多光子量子态的产生--用于计算、计量学和模拟中的应用--需要能够存储宽带脉冲的高效量子存储器网络。将这些存储器集成到光纤中为实现这一目标提供了许多优势：低功率下的强光物质耦合，简化的对准以及与现有光子架构的兼容性。在这里，我们介绍了一个大芯kagome结构的空芯光纤作为一个合适的平台，集成的基于光纤的量子存储器与温暖的原子蒸气。我们证明，第一次，有效的光泵浦空心光子晶体光纤与温暖的原子蒸气，其中（90 $\pm$ 1）%的原子在基态准备。我们测量高光学深度（3 $\times 10^{4}$），也，窄均匀线宽，不表现出显着的渡越时间加宽。我们的研究结果表明，可果美光纤适用于实现宽带，室温量子存储器。

Fibre-optic metadevice for all-optical signal modulation based on coherent absorption

Recently, coherent control of the optical response of thin films of matter in standing waves has attracted considerable attention, ranging from applications in excitation-selective spectroscopy and nonlinear optics to demonstrations of all-optical image processing. Here we show that integration of metamaterial and optical fibre technologies allows the use of coherently controlled absorption in a fully fiberized and packaged switching metadevice. With this metadevice, that controls light with light in a nanoscale plasmonic metamaterial film on an optical fibre tip, we provide proof-of-principle…

Optical Analogue of the Dynamical Casimir Effect in a Dispersion-Oscillating Fibre

The dynamical Casimir effect is the generation of pairs of real particles or photons from the vacuum as a result of a non-adiabatic change of a system parameter or boundary condition. As opposed to standard parametric amplification where the modulation occurs both in space and in time, this fundamental process requires a pure modulation in time, which makes its detection particularly challenging at optical frequencies. In this paper we experimentally demonstrate a realisation of the optical analogue of the mechanical dynamical Casimir effect in the near-infrared optical regime in a dispersion-…

利用多模光纤模式混合和光互易性建立远程密钥

Remote Key Establishment by Mode Mixing in Multimode Fibres and Optical Reciprocity

光子系统中的无序和散射长期以来被认为是应该避免的麻烦。最近，无序已经被用于快速增长的应用，包括成像，传感和光谱学。混沌动力学和对外部扰动的极端敏感性使得随机介质特别适合于光学密码学。然而，使用随机介质在远程用户之间分发密钥仍然具有挑战性，因为它要求用户能够访问相同的散射系统。在这里，我们利用多模光纤中的随机模式混合来同时生成和分发密钥。光纤模式混合中的快速波动为密钥生成提供了随机性的来源，并且光学互易性保证了光纤两端的密钥是相同的。我们通过实验证明了该方案使用经典的光和现成的组件，打开门的成本效益的关键建立在物理层的光纤网络。

为什么补偿光纤非线性永远无法满足容量需求

Why compensating fibre nonlinearity will never meet capacity demands

目前的研究工作集中在克服由于光纤非线性引起的失真而导致的单模光纤中的通信的明显限制。它已被实验证明，这种克尔非线性极限是不是一个基本的限制，因此，它是适当的审查的基本限制光通信的谎言，并在此基础上指导未来的研究。本文详细介绍了最近提出的结果。本文的工作简要回顾了标准单模光纤（SMF）上的光通信的固有限制，并表明石英光纤功率处理和收发器设计的经验限制都引入了一个实际的上限使用SMF的通信容量，在1 Pbit/s的顺序。超过1 Pbit/s的传输速率被证明是可能的，然而，利用目前可用的光纤，通过简单地增加光功率来传输超过该速率的尝试将导致容量的渐进零分数增加。

基于最先进组件的微波频率与光纤干涉测量的灵敏度对比

Sensitivity Comparison of Microwave-Frequency and Optical Fibre Interferometry Based on State-of-the-Art Components

该研究对比了采用微波振荡器与最先进激光器的光纤干涉仪在70km内的振动灵敏度，发现高光谱纯度激光器仅在10Hz以上性能更优，凸显微波低频优势及混合系统潜力。

Generation of optical frequency combs via four-wave mixing processes for low- and medium-resolution astronomy

We investigate the generation of optical frequency combs through a cascade of four-wave mixing processes in nonlinear fibres with optimised parameters. The initial optical field consists of two continuous-wave lasers with frequency separation larger than 40 GHz (312.7 pm at 1531 nm). It propagates through three nonlinear fibres. The first fibre serves to pulse shape the initial sinusoidal-square pulse, while a strong pulse compression down to sub-100 fs takes place in the second fibre which is an amplifying erbium-doped fibre. The last stage is a low-dispersion highly nonlinear fibre where the…

Remote Nanodiamond Magnetometry

Optical fibres have transformed the way people interact with the world and now permeate many areas of science. Optical fibres are traditionally thought of as insensitive to magnetic fields, however many application areas from mining to biomedicine would benefit from fibre-based remote magnetometry devices. In this work, we realise such a device by embedding nanoscale magnetic sensors into tellurite glass fibres. Remote magnetometry is performed on magnetically active defect centres in nanodiamonds embedded into the glass matrix. Standard optical magnetometry techniques are applied to initializ…

Zeeman optical pumping of $^{87}$Rb atoms in a hollow core photonic crystal fibre

Preparation of an atomic ensemble in a particular Zeeman state is a critical step of many protocols for implementing quantum sensors and quantum memories. These devices can also benefit from optical fibre integration. In this work we describe experimental results supported by a theoretical model of single-beam optical pumping of $^{87}$Rb atoms within a hollow-core photonic crystal fibre. The observed 50% population increase in the pumped F=2, m$_F$=2 Zeeman substate along with the depopulation of remaining Zeeman substates enabled us to achieve a 3 times improvement in the relative population…

基于神经网络预测光纤中周期信号的非线性整形

Predicting nonlinear reshaping of periodic signals in optical fibre with a neural network

本研究提出基于神经网络的监督学习模型，可预测光纤中正弦信号经非线性传输后的时域与频域整形效果，覆盖两种色散 regime，还能快速探测参数空间以定制光梳或实现聚焦。

Refractive-index-sensing radio-frequency comb with intracavity multi-mode interference fibre sensor

Optical frequency combs have attracted attention as optical frequency rulers due to their tooth-like discrete spectra together with their inherent mode-locking nature and phase-locking control to a frequency standard. Based on this concept, their applications until now have been demonstrated in the fields of optical frequency metrology and optical distance metrology. However, if the utility of optical combs can be further expanded beyond their optical-frequency-ruler-based application by exploiting new aspects of optical combs, this will lead to new developments in optical metrology and instru…

利用光纤城域网传播高分辨率频标

High Resolution Frequency Standard Dissemination via Optical Fibre Metropolitan Network

本文介绍了标准光纤网络上100 MHz超稳定参考信号的新传播系统的结果。100 MHz信号简单地通过光载波的幅度调制来传输。已经实现了两种不同的方法来补偿由链路引入的噪声。分析了这两种系统的局限性，并提出了几种解决方案，以提高频率稳定度，进一步扩大分布距离。尽管如此，我们的系统是一个很好的工具，最好的冷原子喷泉之间的比较实验室，高达100公里，相对频率分辨率为10-14在一秒的积分时间和10-17一天的测量。可以升级分配系统以满足未来光学时钟的严格分配要求。

非线性光纤信道每孤子容量的一个下界

A Lower Bound on the per Soliton Capacity of the Nonlinear Optical Fibre Channel

本文导出了存在（光）放大器自发辐射（ASE）噪声时非线性光纤信道每孤子容量下限的封闭表达式。这个界限是基于一个非高斯条件概率密度函数的孤子振幅抖动引起的ASE噪声，并被证明增长的信号-噪声比的增加。

Long-range optical trapping and binding of microparticles in hollow-core photonic crystal fibre

Optically levitated micro- and nanoparticles offer an ideal playground for investigating photon-phonon interactions over macroscopic distances. Here we report the observation of long-range optical binding of multiple microparticles, mediated by intermodal scattering and interference inside the evacuated core of a hollow-core photonic crystal fibre (HC-PCF). Three polystyrene particles with 1 μm diameter are stably bound together with an inter-particle distance of ~40 μm, or 50 times longer than the wavelength of the trapping laser. The bound-particle array can be translated to-and-fro over cen…

Nonreciprocal vortex isolator by stimulated Brillouin scattering in chiral photonic crystal fibre

Optical non-reciprocity, which breaks the symmetry between forward and backward propagating optical waves, has become vital in photonic systems and enables many key devices, such as optical isolators, circulators and optical routers. Most conventional optical isolators involve magneto-optic materials, but devices based on optical nonlinearities, optomechanically induced transparency and stimulated Brillouin scattering (SBS) have also been demonstrated. So far, however, they have only been implemented for linearly or randomly polarized LP01-like fundamental modes. Here we report a light-driven …