Unique ultrafast laser part two

Wapaderalaser yachangu kwambirigawo lachiwiri

Kubalalikana ndi kugunda kwa mtima: Kuchedwa kubalalikana kwamagulu
Chimodzi mwamavuto ovuta kwambiri aukadaulo omwe amakumana nawo mukamagwiritsa ntchito ma lasers othamanga kwambiri ndikusunga nthawi yayitali yamphamvu zazifupi zomwe zimatulutsidwa ndilaser. Ma pulses a Ultrafast amatha kusokoneza nthawi, zomwe zimapangitsa kuti ma pulse akhale otalikirapo. Izi zimafika poipa pamene nthawi ya kugunda koyambirira imafupika. Ngakhale ma lasers othamanga kwambiri amatha kutulutsa ma pulse ndi nthawi ya masekondi 50, amatha kukulitsidwa munthawi yake pogwiritsa ntchito magalasi ndi magalasi kuti atumize kugunda komwe mukufuna, kapena kungotumiza kugunda kwake mumlengalenga.

Nthawiyi kupotoza kumayesedwa pogwiritsa ntchito muyeso wotchedwa gulu lochedwa dispersion (GDD), womwe umadziwikanso kuti kufalikira kwachiwiri. Ndipotu, palinso mawu obalalika apamwamba omwe angakhudze nthawi yogawa ma ultrafart-laser pulses, koma pochita, nthawi zambiri zimakhala zokwanira kungoyang'ana zotsatira za GDD. GDD ndi mtengo wodalira pafupipafupi womwe umayenderana ndi makulidwe a chinthu choperekedwa. Zowoneka bwino zopatsirana monga ma lens, zenera, ndi zida zowunikira nthawi zambiri zimakhala ndi zabwino za GDD, zomwe zikuwonetsa kuti ma pulse akakanikizidwa amatha kupangitsa kuti mawonekedwe opatsirana azitalikirapo kuposa omwe amatulutsidwa ndimachitidwe a laser. Zigawo zokhala ndi ma frequency otsika (mwachitsanzo, kutalika kwa mafunde) zimafalikira mwachangu kuposa zigawo zomwe zimakhala ndi ma frequency apamwamba (mwachitsanzo, zazifupi zazitali). Pamene kugunda kumadutsa m'zinthu zowonjezereka, kutalika kwa mafunde mu pulse kumapitirizabe kupitirira nthawi. Kwa nthawi yayifupi ya kugunda kwamtima, chifukwa chake ma bandwidths okulirapo, izi zimakokomeza kwambiri ndipo zimatha kusokoneza kwambiri kugunda kwa nthawi.

Ultrafast laser ntchito
spectroscopy
Chiyambireni magwero a ultrafast laser, spectroscopy yakhala imodzi mwamalo awo ogwiritsira ntchito. Pochepetsa kugunda kwanthawi yayitali kukhala ma femtoseconds kapena ngakhale attoseconds, njira zosinthika mufizikiki, chemistry ndi biology zomwe kale zinali zosatheka kuziwona tsopano zitha kutheka. Chimodzi mwazinthu zofunika kwambiri ndikusuntha kwa atomiki, ndipo kuyang'ana kwa kayendedwe ka atomiki kwathandizira kumvetsetsa kwasayansi kwazinthu zofunikira monga kugwedezeka kwa mamolekyulu, kupatukana kwa mamolekyulu ndi kusamutsa mphamvu mumapuloteni a photosynthetic.

bioimaging
Ma lasers amphamvu kwambiri amathandizira njira zopanda mzere ndikuwongolera malingaliro amalingaliro achilengedwe, monga ma microscope angapo. Mu dongosolo la ma photon ambiri, kuti apange chizindikiro chopanda mzere kuchokera ku biological medium kapena fulorosenti chandamale, ma photon awiri ayenera kugwirizana mu danga ndi nthawi. Njira yosagwirizana ndi njira iyi imathandizira kusintha kwazithunzi pochepetsa kwambiri ma siginecha amtundu wa fluorescence omwe amavutitsa maphunziro a njira za photon imodzi. Kumbuyo kwa chizindikiro chosavuta kumawonetsedwa. Dera laling'ono lachisangalalo la ma multiphoton microscope limaletsanso kuopsa kwa chithunzi ndikuchepetsa kuwonongeka kwa zitsanzo.

Chithunzi 1: Chithunzi chachitsanzo cha njira yamitengo mu kuyesa kwa ma microscope amitundu yambiri

Laser material processing
Ultrafast laser sources yasinthanso laser micromachining ndi kukonza zinthu chifukwa cha njira yapadera yomwe ma ultrashort pulses amalumikizana ndi zida. Monga tafotokozera kale, pokambirana za LDT, nthawi yothamanga kwambiri imakhala yothamanga kwambiri kuposa nthawi ya kutentha kwapang'onopang'ono. Ma lasers a Ultrafast amapanga malo ochepa kwambiri omwe amakhudzidwa ndi kutentha kuposananosecond pulsed lasers, zomwe zimapangitsa kuti pakhale kuwonongeka kochepa komanso makina olondola kwambiri. Mfundoyi imagwiranso ntchito pazachipatala, komwe kuwonjezereka kwachangu kwa kudula kwa ultrafart-laser kumathandiza kuchepetsa kuwonongeka kwa minofu yozungulira ndikuwongolera zochitika za odwala panthawi ya opaleshoni ya laser.

Attosecond pulses: tsogolo la ultrafast lasers
Pamene kafukufuku akupitilira kupititsa patsogolo ma lasers othamanga kwambiri, magwero owunikira atsopano komanso otsogola okhala ndi nthawi yayitali yakugunda akupangidwa. Kuti adziwe zambiri za momwe thupi limagwirira ntchito mwachangu, ofufuza ambiri akuyang'ana kwambiri m'badwo wa attosecond pulses - pafupifupi 10-18 s mumtundu wotalikirapo wa ultraviolet (XUV) wavelength. Ma pulses a Attosecond amalola kutsatiridwa kwa kayendedwe ka ma elekitironi ndikuwongolera kumvetsetsa kwathu kwamapangidwe amagetsi ndi makina a quantum. Ngakhale kuphatikizika kwa XUV attosecond lasers m'mafakitale sikunapite patsogolobe, kafukufuku wopitilira ndi kupita patsogolo m'gawoli kudzakankhira ukadaulo uwu kuchoka mu labu ndi kupanga, monga momwe zakhalira ndi femtosecond ndi picosecond.magwero a laser.