Yn ddiweddar, Canolfan Russell ar gyfer Gwyddoniaeth Lightwave Uwch Sefydliad Opteg a Mecaneg Gain Hangzhou, Prifysgol Gwyddoniaeth a Thechnoleg y Cenhedloedd Unedig Sefydliad Hangzhou dros Astudiaethau Uwch, Sefydliad Opteg Shanghai a Mecaneg Precision Academi Gwyddorau Tsieineaidd, ac Ifibo (Ningbo) 1 COOS}}}}}}}}} Canlyniadau yn y cyfnodolyn optegol gorau rhyngwladol "Optica", ac am y tro cyntaf cyflawnodd effeithlonrwydd uchel, ffyddlondeb uchel a phurdeb purdeb un modd uchel trosglwyddiad hyblyg lefel bron-wat, cannoedd o femtoseconds, 2 {. 8 μm pcf band canol-greon-craidd-creonig gwag-creonig ffotonig gras-creonig. Mae'r canlyniad hwn nid yn unig yn darparu datrysiad effeithiol i ddiffygion corbys ultrafast canol-is-goch wrth drosglwyddo, ond hefyd yn gosod y sylfaen ar gyfer ehangu cymwysiadau laser canol-is-goch
High-power mid-infrared ultrafast broadband light sources have important applications in advanced spectroscopy, material fine processing, medical surgery, and remote sensing. The limitations of laser transmission have hindered the further expansion of mid-infrared laser applications. In traditional transmission methods, the absorption of various gas molecules in the spatial optical path causes deformation of the output light spot and deterioration of pulse quality. Solid mid-infrared optical fiber has serious nonlinear accumulation, which causes serious distortion of the output time-frequency signal. To solve this problem, the research team used a self-made single-hole eight-ring structure Hollow-core PCF (length 5 m) to transmit mid-infrared ultrafast pulses. Thanks to the advantages of low transmission loss, low nonlinear effect accumulation and support for rapid vacuum extraction of Hollow-core PCF, the team not only solved the problems caused by traditional transmission methods, but also successfully achieved efficient transmission with an overall efficiency of >70%.
During the experiment, the experimenters used a self-built mid-infrared pulse fiber laser as the light source and a 5 m long Hollow-core PCF as the transmission medium. The two ends of the Hollow-core PCF were fixed in the air chamber so that the Hollow-core PCF could be evacuated using a vacuum pump. After the vacuum was drawn (the entire extraction process took less than 1 minute, and the gas pressure was drawn to ~10 mbar), the team successfully achieved an overall laser efficiency of > 70%, a Gaussian spot output that was close to the diffraction limit, and the entire system showed excellent stability. In addition, the spectral shape of the output in the frequency domain was basically consistent with the input. In the time domain, due to the small amount of waveguide dispersion of the hollow-core PCF (-2.04 fs2/mm @ 2.8 μm), the pulse width was widened from the input 117 fs to 404 fs. Subsequently, the experimenters added Ge and ZnSe positive dispersion materials to compensate for the negative dispersion introduced by the hollow-core PCF, coupling lens and air chamber window, and obtained an output with a pulse width of 98 fs (close to the transformation limit pulse width of 96 fs), with a peak power of 170 kW. In addition, the experimenters also used the autocorrelation trace to estimate that the output fundamental mode energy accounted for >95%.
Cymharodd yr arbrofwyr hefyd y cynllun trosglwyddo â'r llwybr optegol gofodol o'r un hyd a'r ffibr fflworid craidd solid . Mae'r canlyniadau'n dangos, wrth drosglwyddo corbys ultrafast mewn ffibrau fflworid craidd solet, bod yr effaith aflinol yn rhy gryf, gan arwain at rannu pwls, y mae pwls yn gwahanu ac yn gwahanu. Ffibrau Crystal Wrth drosglwyddo corbys pŵer canol-is-goch Ultrafast . Cyflawnodd yr arbrawf dechnoleg trosglwyddo laser canol-is-haenog purdeb uchel-is-haen uchel, gan osod sylfaen dda ar gyfer cymhwyso band llydan, gan osod sylfaen eang, ar gyfer cymhwyso band llydan, ar gyfer cymhwyso Synhwyro .
Cyhoeddwyd y canlyniadau ymchwil perthnasol yn The Top Journal of Lasers and Optoelectroneg, Optica, gyda'r teitl "Dosbarthu Hyblyg o Fand Eang, 100 FS Corbys canol-is-goch yn y Band Amsugno Dŵr gan ddefnyddio Ffibr Crystal Ffotonig Hollow-craidd" . Gwyddoniaeth SHANGITION ANCTICTION ANTOCTION ANTOCTIONATE ANTOCTIONAH ANTCITTIONS ANCTICTIONS Y Sefydliad Technoleg Uwch, a Li Zeqing, myfyriwr doethuriaeth yn Sefydliad Opteg a Mecaneg Cain Shanghai, yw'r awduron cyd-gyntaf, a Huang Jiapeng, Jiang Xin a Pang Meng o Ganolfan Russell yw'r awduron cyd-gyfatebol {.
Ffigur 1. Gosodiad arbrofol a chanlyniadau . (a) llwybr optegol arbrofol . lens, lens plano-convex CAF2 wedi'i orchuddio; HWP, plât hanner ton; QWP, plât chwarter ton; Fm, drych plygu; FTIR, Sbectromedr Is -goch Trawsnewid Fourier; AC, autocorrelator. (b) SEM image of the fiber structure. (c) Loss spectrum measured using the truncation method, the shaded area represents the measurement uncertainty (orange, left axis), and the calculated dispersion curve (blue, right axis). (d) Output power through a 5- metr o hyd pcf gwag-craidd . (e) gan ddefnyddio deunyddiau 30 mm znse a 5 mm GE, cyflawnwyd allbwn pwls gyda lled pwls bron-drawsffurfiad o 98 fs {.
Ffigur 2. Cymhariaeth o wahanol ddulliau trosglwyddo . (a) sbectrwm amsugno normaleiddiedig anwedd dŵr . (b) allbwn laser uniongyrchol (llwyd) a sbectrwm trawsyrru yn y sbectrwm gwag (puro puro), porffor), porffor), puro yn y sbectrwm (puro), puro yn y sbectrwm gwactod (coch) . Mae'r ochr dde yn dangos y sbectrwm chwyddedig yn yr ystod o 2.7-2.8 μm . (c) Cynhyrchu soliton Raman mewn ffibr fflworid craidd solet {{}} ar y chwith ac mae'r sbectrwm FTIR} ar y chwith ar y chwith a thorri'r ddeocor
