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盾牌δ型变星HD213534的多重频率

天文学报 1992年第3期33卷 327-336页

作者：傅建宁蒋世仰 E.MICHEL J.A.BELMONTE M.ALVAREZ M.CHEVRETON M.AUVERGNE M.J.GOUPIL A.BAGLIN a.mangeney M.CHALOUPI T.ROCA CORTES 江西大学物理系南昌330047 中国科学院北京天文台北京100080 Observatoire de Paris-Meudon MeudonFrance Instituto de Astrofisica Canarias TenerifeSpain Instituto de Astronomia Universidad National AutonomaMexico

本文利用三国联合观测获得的大量高精度光电测光数据,采用Fourier周期分析的方法,得到了δScuti型变星HD213534的多重脉动周期,认为该星存在五个以上的脉动频率.文中给出了该星的各项参量,并对其脉动模式进行了讨论,认为HD213534星是一... 详细信息

本文利用三国联合观测获得的大量高精度光电测光数据,采用Fourier周期分析的方法,得到了δScuti型变星HD213534的多重脉动周期,认为该星存在五个以上的脉动频率.文中给出了该星的各项参量,并对其脉动模式进行了讨论,认为HD213534星是一颗以非径向脉动为主的多重周期脉动变星.

关键词：周期分析变星 δ型测光频率

High Q and sub-wavelength THz electric field confinement in ultrastrongly coupled THz resonators

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光子学研究:英文版 2023年第7期11卷 1203-1216页

作者： SIMON MESSELOT SOLEN COEYMANS JEROME TIGNON SUKHDEEP DHILLON JULIETTE mangeney Laboratoire de Physique de l’Ecole Normale Supérieure Ecole normale supérieurePSL UniversitySorbonne UniversitéUniversitéParis DiderotSorbonne Paris CitéCNRS24 rue Lhomond75005 ParisFrance

The control of light–matter coupling at the single electron level is currently a subject of growing interest for the development of novel quantum devices and for studies and applications of quantum *** the terahertz(THz)spectral range,this raises the particular and difficult challenge of building electromagnetic resonators that can conciliate low mode volume and high quality ***,we report on hybrid THz cavities based on ultrastrong coupling between a Tamm cavity and an LC circuit metamaterial and show that they can combine high quality factors of up to Q=37 with a deep-subwavelength mode volume of V=3.2×10^(-4)λ^(3).Our theoretical and experimental analysis of the coupled mode properties reveals that,in general,the ultrastrong coupling between a metamaterial and a Fabry–Perot cavity is an effective tool to almost completely suppress radiative losses and,thus,ultimately limit the total losses to the losses in the metallic *** Tamm cavity-LC metamaterial coupled resonators open a route toward the development of single photon THz emitters and detectors and to the exploration of ultrastrong THz light–matter coupling with a high degree of coherence in the few to single electron limit.

关键词： coupling cavity coupled

Layer-controlled nonlinear terahertz valleytronics in two-dimensional semimetal and semiconductor PtSe_(2)

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InfoMat 2023年第11期5卷 49-63页

作者： Minoosh Hemmat Sabrine Ayari Martin Micica Hadrien Vergnet Shasha Guo Mehdi Arfaoui Xuechao Yu Daniel Vala Adrien Wright Kamil Postava Juliette mangeney Francesca Carosella Sihem Jaziri Qi Jie Wang Zheng Liu Jérôme Tignon Robson Ferreira Emmanuel Baudin Sukhdeep Dhillon Laboratoire de Physique de l'Ecole normale supérieure ENSUniversitéPSLCNRSSorbonne UniversitéUniversitéde Paris-CitéParisFrance School of Materials Science and Engineering Nanyang Technological UniversitySingaporeSingapore Laboratoire de Physique de la Matière Condensée Département de PhysiqueFacultédes Sciences de TunisUniversitéTunis El ManarCampus UniversitaireTunisTunisia Key Laboratory of Multifunctional Nanomaterials and Smart Systems Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhouJiangsuthe People's Republic of China IT4Innovations National Supercomputing CenterVSB—Technical University of OstravaOstrava-PorubaCzech Republic Faculty of Materials Science and Technology VSB—Technical University of OstravaOstrava-PorubaCzech Republic School of Electrical and Electronic Engineering&School of Physical and Mathematical Sciences The Photonics InstituteNanyang Technological UniversitySingaporeSingapore

Platinum diselenide(PtSe_(2))is a promising two-dimensional(2D)material for the terahertz(THz)range as,unlike other transition metal dichalcogenides(TMDs),its bandgap can be uniquely tuned from a semiconductor in the nearinfrared to a semimetal with the number of atomic *** gives the material unique THz photonic properties that can be ***,we demonstrate that a controlled THz nonlinearity—tuned from monolayer to bulk PtSe_(2)—can be realized in wafer size polycrystalline PtSe_(2)through the generation of ultrafast photocurrents and the engineering of the bandstructure *** is combined with the PtSe_(2)layer interaction with the substrate for a broken material centrosymmetry,permitting a second order ***,we show layer dependent circular dichroism,where the sign of the ultrafast currents and hence the phase of the emitted THz pulse can be controlled through the excitation of different bandstructure *** particular,we show that a semimetal has a strong dichroism that is absent in the monolayer and few layer semiconducting *** microscopic origins of this TMD bandstructure engineering are highlighted through detailed DFT simulations,and shows the circular dichroism can be controlled when PtSe_(2)becomes a semimetal and when the K-valleys can be *** well as showing that PtSe_(2)is a promising material for THz generation through layer controlled optical nonlinearities,this work opens up a new class of circular dichroism materials beyond the monolayer limit that has been the case of traditional TMDs,and impacting a range of domains from THz valleytronics,THz spintronics to harmonic generation.

关键词： 2D transition metal dichalcogenides Dirac semimetal optical nonlinearities terahertz valleytronics

Ultrafast response of harmonic modelocked THz lasers

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Light(Science & Applications) 2020年第1期9卷 1530-1537页

作者： Feihu Wang Valentino Pistore Michael Riesch Hanond Nong Pierre-Baptiste Vigneron Raffaele Colombelli Olivier Parillaud Juliette mangeney Jerome Tignon Christian Jirauschek Sukhdeep S.Dhillon Laboratoire de Physique de l’Ecole Normale Superieure ENSUniversite PSLCNRSSorbonne UniversiteUniversite de ParisParisFrance Department of Electrical and Computer Engineering Technical University of MunichArcisstr.2180333 MunichGermany Centre de Nanosciences et de Nanotechnologies CNRSUniv.Paris-SudUniversite Paris-SaclayC2N-Orsay91405 OrsayCedexFrance Ⅲ-ⅤLab 1 avenue Augustin Fresnel91767 PalaiseauFrance

The use of fundamental modelocking to generate short terahertz(THz)pulses and THz frequency combs from semiconductor lasers has become a routine affair,using quantum cascade lasers(QCLs)as a gain ***,unlike classic laser diodes,no demonstrations of harmonic modelocking,active or passive,have been shown in THz QCLs,where multiple pulses per round trip are generated when the laser is modulated at the harmonics of the cavity’s fundamental round-trip ***,using time-resolved THz techniques,we show for the first time harmonic injection and mode-locking in which THz QCLs are modulated at the harmonics of the round-trip *** demonstrate the generation of the harmonic electrical beatnote within a QCL,its injection locking to an active modulation and its direct translation to harmonic pulse generation using the unique ultrafast nature of our ***,we show indications of self-starting harmonic emission,i.e.,without external modulation,where the QCL operates exclusively on a harmonic(up to its 15th harmonic)of the round-trip *** behaviour is supported by time-resolved simulations of induced gain and loss in the system and shows the importance of the electronic,as well as photonic,nature of *** results open up the prospect of passive harmonic modelocking and THz pulse generation,as well as the generation of low-noise microwave generation in the hundreds of GHz region.

关键词： passive harmonic harmonics

Cavity-based photoconductive sources for real-time terahertz imaging

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Photonics Research 2020年第6期8卷 858-863页

作者： J.HAWECKER V.PISTORE A.MINASYAN K.MAUSSANG J.PALOMO I.SAGNES J.-M.MANCEAU R.COLOMBELLI J.TIGNON J.mangeney AND S.S.DHILLON Laboratoire de Physique de I'Ecole normale superieure ENSUniversite PSLCNRSSorbonne UniversiteUniversite de ParisF-75005 ParisFrance i2S 28-30 rue Jean Perrin 33608 PessacFrance Centre de Nanosciences et de Nanotechnologies(C2N) CNRS UMR 9001Universite Paris-Saclay91120 PalaiseauFrance Institut d'Electronique et des Systemes CNRS(UMR 5214)Univ Montpellier860 rue de Saint-Priest34095 Montpellier Cedex 5France

Optically driven photoconductive switches are one of the predominant sources currently used in terahertz im-aging ***,owing to their low average powers,only raster-based images can be taken,resulting in slow *** this work,we show that by placing a photoconductive switch within a cavity,we are able to generate absolute average THz powers of 181μW with the frequency of the THz emission centered at 1.5 THz-specifications ideally adapted to applications such as non-destructive *** cavity is based on a metal-insulator-metal structure that permits an en hancement of the average power by almost 1 order of magnitude compared to a standard structure,while conserving a broadband spectral *** demonstrate proof-of-principle real-time imaging using this source,with the broadband spectrum permitting to eliminate strong diffraction artifacts.

关键词： photoconductive sources cavity