Gawo lachiwiri la laser lapadera la ultrafast

Zapaderalaser yothamanga kwambirigawo lachiwiri

Kufalikira ndi kufalikira kwa kugunda kwa mtima: Gulu limachedwetsa kufalikira kwa magazi
Chimodzi mwa mavuto ovuta kwambiri aukadaulo omwe amakumana nawo pogwiritsa ntchito ma laser othamanga kwambiri ndi kusunga nthawi ya ma pulse afupi kwambiri omwe amatulutsidwa koyamba ndilaserMa pulse othamanga kwambiri amakhala pachiwopsezo chachikulu cha kusokonezeka kwa nthawi, zomwe zimapangitsa kuti ma pulse akhale aatali. Izi zimakula kwambiri pamene nthawi ya pulse yoyamba ikufupika. Ngakhale ma laser othamanga kwambiri amatha kutulutsa ma pulse okhala ndi masekondi 50, amatha kukulitsidwa pakapita nthawi pogwiritsa ntchito magalasi ndi magalasi kuti atumize pulse kumalo omwe akufuna, kapena kungotumiza pulse kudzera mumlengalenga.

Kusokonezeka kwa nthawi imeneyi kumayesedwa pogwiritsa ntchito muyeso wotchedwa group delayed dispersion (GDD), womwe umadziwikanso kuti second-order dispersion. Ndipotu, palinso mawu oti dispersion apamwamba omwe angakhudze kufalikira kwa nthawi kwa ma pulse a ultrafart-laser, koma m'machitidwe, nthawi zambiri kumakhala kokwanira kungoyang'ana momwe GDD imagwirira ntchito. GDD ndi mtengo wodalira pafupipafupi womwe umagwirizana ndi makulidwe a chinthu china. Ma transmission optics monga lens, window, ndi objective components nthawi zambiri amakhala ndi ma GDD abwino, zomwe zikusonyeza kuti ma pulses akapanikizika amatha kupatsa ma transmission optics nthawi yayitali kuposa omwe amatulutsidwa ndimakina a laserZigawo zomwe zili ndi ma frequency otsika (monga, ma wavelength ataliatali) zimafalikira mofulumira kuposa zigawo zomwe zili ndi ma frequency apamwamba (monga, ma wavelength aafupi). Pamene kugunda kwa mtima kumadutsa m'zinthu zambiri, ma wavelength mu kugunda kwa mtima adzapitirira kufalikira kwambiri pakapita nthawi. Pa nthawi yochepa ya kugunda kwa mtima, komanso chifukwa cha ma bandwidth ochulukirapo, izi zimakokedwa kwambiri ndipo zingayambitse kusokonezeka kwakukulu kwa nthawi ya kugunda kwa mtima.

Kugwiritsa ntchito laser ya Ultrafast
spectroscopy
Kuyambira pomwe magwero a laser othamanga kwambiri adayamba, spectroscopy yakhala imodzi mwamagawo omwe amagwiritsidwa ntchito kwambiri. Mwa kuchepetsa nthawi ya kugunda kwa mtima kukhala femtoseconds kapena ngakhale attoseconds, njira zosinthika mu fizikisi, chemistry ndi biology zomwe zinali zosatheka kuziwona tsopano zitha kuchitika. Chimodzi mwa njira zofunika kwambiri ndi kuyenda kwa atomu, ndipo kuwona kuyenda kwa atomu kwawongolera kumvetsetsa kwasayansi kwa njira zoyambira monga kugwedezeka kwa mamolekyulu, kugawanika kwa mamolekyulu ndi kusamutsa mphamvu mu mapuloteni opanga photosynthesis.

kujambula zithunzi za moyo
Ma laser amphamvu kwambiri amathandizira njira zosalunjika komanso kukonza mawonekedwe a zithunzi zamoyo, monga ma microscopy a multi-photon. Mu dongosolo la multi-photon, kuti apange chizindikiro chosakhala cholunjika kuchokera ku chamoyo kapena cha fluorescent, ma photon awiri ayenera kusakanikirana mumlengalenga ndi nthawi. Njira yosakhala yolunjika iyi imawongolera mawonekedwe a zithunzi mwa kuchepetsa kwambiri zizindikiro za fluorescence zakumbuyo zomwe zimavutitsa maphunziro a njira za single-photon. Chithunzi chosavuta cha chizindikiro. Dera laling'ono la kusangalatsa la multiphoton microscope limatetezanso poizoni wa photon ndikuchepetsa kuwonongeka kwa chitsanzo.

Chithunzi 1: Chitsanzo cha chithunzi cha njira ya beam mu kuyesa kwa maikulosikopu ya photon yambiri

Kukonza zinthu za laser
Magwero a laser othamanga kwambiri asinthanso ntchito ya laser micromachining ndi kukonza zinthu chifukwa cha njira yapadera yomwe ma pulse afupifupi amagwirira ntchito ndi zinthu. Monga tanenera kale, pokambirana za LDT, nthawi ya pulse yothamanga kwambiri imakhala yachangu kuposa nthawi yomwe kutentha kumafalikira mu lattice ya zinthuzo. Ma laser othamanga kwambiri amapanga malo ochepa kwambiri omwe amakhudzidwa ndi kutentha kuposama laser opangidwa ndi nanosecond, zomwe zimapangitsa kuti pakhale kuchepa kwa kudula ndi makina olondola kwambiri. Mfundo imeneyi imagwiranso ntchito pa ntchito zachipatala, komwe kulondola kwambiri kwa kudula kwa laser ya ultrafart kumathandiza kuchepetsa kuwonongeka kwa minofu yozungulira ndikuwonjezera zomwe wodwala akuchita pa opaleshoni ya laser.

Ma pulse a Attosecond: tsogolo la ma laser othamanga kwambiri
Pamene kafukufuku akupitiliza kupititsa patsogolo ma laser othamanga kwambiri, magwero atsopano komanso abwinoko a kuwala omwe amakhala ndi nthawi yochepa ya pulse akupangidwa. Kuti amvetsetse bwino momwe zinthu zimayendera mwachangu, ofufuza ambiri akuyang'ana kwambiri pakupanga ma attosecond pulse - pafupifupi masekondi 10-18 mu utali wa wavelength wa ultraviolet (XUV). Ma Attosecond pulse amalola kutsatira kayendedwe ka ma elekitironi ndikuwongolera kumvetsetsa kwathu kapangidwe ka zamagetsi ndi makina a quantum. Ngakhale kuphatikiza ma XUV attosecond lasers mu njira zamafakitale sikunapite patsogolo kwambiri, kafukufuku wopitilira ndi kupita patsogolo m'mundawu kudzachotsa ukadaulo uwu mu labu ndikupanga, monga momwe zakhalira ndi femtosecond ndi picosecond.magwero a laser.