Modes trimming and clustering in a weakly perturbed high- Q whispering gallery microresonator Botao Fu17 Renhong Gao16 Jintian Lin16 Ni Yao2 Haisu Zhang3 Min Wang3 Lingling

2025-05-06 0 0 2.46MB 19 页 10玖币

侵权投诉

Modes trimming and clustering in a weakly perturbed high-Q

whispering gallery microresonator

Botao Fu,1,7 Renhong Gao,1,6 Jintian Lin,1,6 Ni Yao, 2,† Haisu Zhang,3 Min Wang,3 Lingling

Qiao,1,6 Wei Fang,5 and Ya Cheng1,3,4,6,8,9,10,11,*

1State Key Laboratory of High Field Laser Physics and CAS Center for Excellence in Ultra-Intense Laser

Science, Shanghai Institute of Optics and Fine Mechanics (SIOM), Chinese Academy of Sciences (CAS),

Shanghai 201800, China

2Research Center for Humanoid Sensing, Zhejiang Lab, Hangzhou 311100, China

3The Extreme Optoelectromechanics Laboratory (XXL), School of Physics and Electronic Science, East

China Normal University, Shanghai 200241, China

4State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062,

China

5Interdisciplinary Center for Quantum Information, State Key Laboratory of Modern Optical

Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027,

China

6Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of

Sciences, Beijing 100049, China

7School of Physical Science and Technology, Shanghai Tech University, Shanghai 200031, China

8Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China

9Collaborative Innovation Center of Light Manipulations and Applications, Shandong Normal University,

Jinan 250358, China

10Shanghai Research Center for Quantum Sciences, Shanghai 201315, China

11Hefei National Laboratory, Hefei 230088, China

†Electronic address: yaoni14@zju.edu.cn

*Electronic address: ya.cheng@siom.ac.cn

Abstract

In general, a high-Q microresonator can accommodate abundant whispering gallery

modes (WGMs) with the mode number increasing with the dimensional sizes of the

microresonator. Removing the unnecessary modes while reorganizing the remaining

modes is of vital importance, which, however, has been proved challenging and usually

results in a tradeoff with the Q of the microresonator. Here, we reveal an effective and

controllable mode trimming and clustering mechanism underlying the generation of

polygon and star modes in weakly perturbed tapered fiber-coupled lithium niobate

whispering gallery microresonators. Experimentally, various polygon and star modes

are observed in sequence within a single microresonator by tuning the excitation

wavelength or varying the coupling position between a tapered fiber and the circular

microresonator, which can be well reproduced with our theoretical model. The finding

offers a ubiquitous solution for a broad range of applications requiring elaborate

selection and organization of the high-Q WGMs.

Optical dielectric microresonators, which enhance light-matter interaction by storing

optical energy in a small mode volume with ultra-low loss [1-4], are now highly

desirable not only to fundamental physics such as chaos-assisted tunnelling [5, 6] and

cavity quantum electrodynamics [7, 8] but also to practical applications from integrated

laser sources [9-12], to sensors [13-15] and modulators [16, 17]. Among the diverse

candidates, circular-shaped whispering gallery mode (WGM) microresonators have

been intensively studied due to their nearly perfect light confinement over a long period.

The isotropic characteristic in the microdisk plane is unfavourable for either intensive

interaction of the light field with the coupled device or efficient emission collection,

which is the reason behind the significant efforts spent on the deformed WGM

microdisks [18-21]. Unfortunately, the microresonator deformation usually leads to the

reduction of the mode Q factor and in turn the light-matter interaction strength. Recently,

the generation of high-Q polygon modes in tapered fiber-coupled circular microdisk

resonators with weak perturbation has been reported [22, 23], whereas the essential

physics behind the phenomena is yet to be explored and clarified.

Here, we reveal an effective and controllable mechanism to precisely conduct the mode

trimming and clustering in a weakly perturbed tapered fiber-coupled lithium niobate

WGM microresonator. Meanwhile, complete polygon and star modes sequences are

observed within the single microresonator, which are well reproduced with our

theoretical model.

To facilitate observation of mode patterns, an Er3+-doped z-cut lithium niobate circular

microdisk resonator allowing visualization of the modes is utilized taking advantage of

two-photon fluorescence excitation of the Er3+ ions. The circular microdisk resonator

was fabricated using photolithography-assisted chemo-mechanical etching, and further

details on the fabrication procedures can be found in Ref. [24-26]. The inset of Fig. 1(a)

shows the scanning-electron-microscope (SEM) image of the fabricated microdisk

resonator with a thickness of 700 nm and a diameter of 83.44 μm.

The experimental setup for investigating the polygon and star modes formation is

illustrated in Fig. 1(a), in which a narrow-linewidth tunable diode laser with a

wavelength range from 960 nm to 980 nm (Model: TLB-6719-P-D, New Focus, Inc.)

is used as the pump light source. The pump light is coupled to the microdisk via the

tapered fiber with a diameter of 2 μm [27], and the polarization state can be controlled

to be transverse-magnetically polarized by an in-line polarization controller (PC). The

input pump power can be adjusted and monitored by a variable optical attenuator (VOA)

and a power meter combined with a 10/90 beam splitter. The relative position between

the tapered fiber and microdisk resonator can be monitored and adjusted by an optical

microscope system and a high-resolution positioning stage of 5 nm resolution. A top-

view optical microscope with a 20× objective lens with a numerical aperture of 0.42,

a visible charge-coupled device (CCD), and a short-pass filter (Model: FES800,

Thorlabs, Inc.) are used to capture the mode patterns distributed on the plane of the

microdisk. Remarkably, the captured up-conversion fluorescence patterns directly

reflect the spatial distribution characterisitics of the pump mode [23].

文档加载中……请稍候！
如果长时间未打开，您也可以点击刷新试试。

下载文档到电脑，查找使用更方便

10 玖币 0人已下载

立即下载

摘要：

Modestrimmingandclusteringinaweaklyperturbedhigh-QwhisperinggallerymicroresonatorBotaoFu,1,7RenhongGao,1,6JintianLin,1,6NiYao,2,†HaisuZhang,3MinWang,3LinglingQiao,1,6WeiFang,5andYaCheng1,3,4,6,8,9,10,11,*1StateKeyLaboratoryofHighFieldLaserPhysicsandCASCenterforExcellenceinUltra-IntenseLaserScience,S...

展开>> 收起<<

Modes trimming and clustering in a weakly perturbed high- Q whispering gallery microresonator Botao Fu17 Renhong Gao16 Jintian Lin16 Ni Yao2 Haisu Zhang3 Min Wang3 Lingling.pdf

共19页,预览4页

还剩页未读，继续阅读

声明：本站为文档C2C交易模式，即用户上传的文档直接被用户下载，本站只是中间服务平台，本站所有文档下载所得的收益归上传人(含作者)所有。玖贝云文库仅提供信息存储空间，仅对用户上传内容的表现方式做保护处理，对上载内容本身不做任何修改或编辑。若文档所含内容侵犯了您的版权或隐私，请立即通知玖贝云文库，我们立即给予删除！

Modes trimming and clustering in a weakly perturbed high- Q whispering gallery microresonator Botao Fu17 Renhong Gao16 Jintian Lin16 Ni Yao2 Haisu Zhang3 Min Wang3 Lingling

相关推荐

开通VIP享超值会员特权

作者详情

相关内容

热门标签

举报选择: