Faʻatupuina o le octave-spanning mid-infrared e faʻaaoga ai le BGSe nonlinear tioata

Dr.JINWEI ZHANG ma lana 'au o loʻo faʻaaogaina le Cr: ZnS leisa polokalama tuʻuina atu 28-fs uaua i le ogatotonu wavelength o 2.4 µm o loʻo faʻaaogaina o le pamu punaoa, lea e faʻaosofia ai le tele-uaua eseesega eseesega taimi i totonu o le BGSe tioata. O lona iʻuga, o se fesoʻotaʻiga fesoʻotaʻiga fesoʻotaʻi ogatotonu-infrared faaauau mai le 6 i le 18 µm ua maua. O loʻo faʻaalia mai o le BGSe tioata o se mea taua mo broadband, nai-taʻamilosaga ogatotonu-infrared augatupulaga ala i lalo o lalo liua ma femtosecond pamu mafuaʻaga.

Faatomuaga

Mid-infrared (MIR) malamalama i le vaega o le 2-20 µm e aoga mo vailaʻau ma faʻamaoniga moni ona o le i ai o le tele o vaega mole mole faʻatamaʻiaina laina i lenei spectral itulagi. O se fesoʻotaʻiga, nai-taʻamilosaga faʻavae ma le tutusa faʻamatalaga o le lautele MIR tele mafai mafai atili mafai ai fou polokalama pei o mirco-spectroscopy, femtosecond pamu-suʻesuʻeina spectroscopy, ma maualuga-malosi-tele maʻaleʻale fuaina Seʻi oʻo mai nei tele polokalame ua
na atiaʻe e faʻatupuina MIR radiation talafeagai, pei o laina synchrotron beam, quantum cascade lasers, supercontinuum punavai, opitika parametric oscillators (OPO) ma opitika parametric amplifier (OPA). O nei polokalame uma lava latou malosiʻaga ma vaivaiga i tulaga o faigata, bandwidth, paoa, lelei atoatoa, ma taimi umi uaua. Faʻatasi ai ma i latou, intra-pulse eseesega taimi faʻasolosolo (IDFG) o tosina faʻateleina mafaufau faʻafetai i le atinaʻeina o le maualuga-paoa femtosecond 2 µm lasers e mafai lelei pamu laʻititi-bandgap leai-oxide nonlinear tioata e fausia maualuga-malosi broadband ogatasi MIR malamalama. Faʻatusatusa i le masani ona faʻaaogaina OPOs ma OPAs, IDFG faʻatagaina le faʻaititia o le faigata o le tino ma le faʻalauteleina o le faʻatuatuaina, ona o le manaʻoga e faʻavasega lua vavae eseʻese poʻo lua i le maualuga maualuga ua aveʻesea. E le gata i lea, o le MIR galuega faatino o loʻo feaveaʻi feaveaʻi-teutusi-vaega (CEP) mautu ma IDFG.

Ata 1

Auina atu fusi o alaleo o le 1-mm-mafiafia uncoated BGSe tioata saunia e DIEN TECH. O le inset faʻaalia ai le tioata moni na faʻaaogaina i lenei faʻataʻitaʻiga.

Ata 2

Faʻataʻitaʻiga faʻatulagaina o le MIR augatupulaga ma le BGSe tioata. OAP, ese-axis parabolic faʻata ma le lelei taulaʻi umi o le 20 mm; HWP, afa-galu ipu; TFP, manifinifi ata tifaga polarizer; LPF, faamama umi-pasi.

I le 2010, o se fou biaxial chalcogenide nonlinear tioata, BaGa4Se7 (BGSe), na fausiaina faʻaaogaina ai le auala Bridgman-Stockbarger. E i ai lona lautele lautele manino mai 0.47 i le 18 µm (e pei ona faʻaalia i le Fig 1) ma nonlinear coefficients o d11 = 24.3 pm / V ma d13 = 20.4 pm / V. O le faʻamalama manino o le BGSe e lautele lautele atu nai lo ZGP ma LGS e ui o lona nonlinearity e maualalo nai lo ZGP (75 ± 8 pm / V). E faʻatusatusa i le GaSe, e mafai foi ona tipi le BGSe i le itu e manaʻomia vaega-tutusa ma mafai ona avea ma aneti-ata lafoia.

O le faʻataʻitaʻiga seti o loʻo faʻaalia i le Ata 2 (a). O le avega paʻu na muamua fausia mai le fausiaina Kerr-tioata faiga-loka Cr: ZnS oscillator ma le polycrystalline Cr: ZnS tioata (5 × 2 × 9 mm3, auina atu = 15% i 1908nm) o le mauaina auala pamuina e se Tm-doped alava leisa i le 1908nm. O le oscillation i totonu o se tulaga o galu e tuʻuina mai ai ni fuluʻu e 45-fs o loʻo faʻatautaia i le toe faia o le 69 MHz ma le malosi masani o le 1 W i le umi o le feaveaʻiga o le 2.4 µm. O le malosiaga ua faʻateleina i le 3.3 W i totonu o le fale-fausia lua-tulaga tasi-pasi polycrystalline Cr: ZnS amplifier (5 × 2 × 6 mm3, faʻasalalauga = 20% i le 1908nm ma le 5 × 2 × 9 mm3, faʻaliliuga = 15% i 1908nm), ma le faʻatinoina o le pulse Duration o loʻo fuaina ma le fale e fausia i le fale lona lua-feololo-ogaoga taimi-fofo opitika valavala (SHG-FROG) mea faigaluega.

DSC_0646Faaiuga

Na latou faʻaalia se faʻavae MIR ma le BGSe tioata faʻavae i luga ole metotia IDFG. O le femtosecond Cr: ZnS laser system i le wavelength o le 2.4 µm na faʻaaogaina e avea ma auala e aveina ai le taʻavale, faʻatagaina ai le taimi e tasi e faʻailoaina mai ai le spectral mai le 6 i le 18 µm. I le sili atu o lo matou iloa, o le taimi muamua lenei broadband MIR augatupulaga na mauaina i totonu o le BGSe tioata. O le galuega faatino o loʻo faʻamoemoe e i ai ni nai taʻamilosaga o le taofiga o taimi ma e faʻapea foi ona mautu i lona vaega feaveaʻi-teutusi. Faʻatusatusa i isi tioata, o le amataga faʻaiuga ma BGSe faʻaalia ai se MIR augatupulaga ma tutusa lautele bandwidth (lautele atu nai lo ZGP ma LGS) e ui lava ma le maualalo averesi mana ma liua lelei. Maualuga averesi mana mafai faamoemoeina ma nisi optimization o le taulaʻi nofoaga lapoʻa ma tioata mafiafia. O se sili atu le lelei tioata ma maualuga maualuga faʻavaitaimi o le a aoga foi mo le faʻateleina o le MIR averesi mana ma liua lelei. Lenei galuega faʻaalia ai o le BGSe tioata o se folafolaga mea mo le broadband, soofaatasi MIR augatupulaga.
Taimi Post: Tes-07-2020