Hauv kev tshaj tawm tseem ceeb rau yav tsaus ntuj ntawm lub Kaum Hli 3, 2023, qhov khoom plig Nobel hauv Physics rau xyoo 2023 tau tshaj tawm, lees paub cov kev pabcuam zoo ntawm peb tus kws tshawb fawb uas tau ua lub luag haujlwm tseem ceeb ua cov thawj coj hauv lub ntiaj teb ntawm attosecond laser technology.

Lo lus "attosecond laser" tau txais nws lub npe los ntawm lub sijhawm luv luv uas nws ua haujlwm, tshwj xeeb tshaj yog nyob rau hauv qhov kev txiav txim ntawm attoseconds, sib raug rau 10 ^ -18 vib nas this. Yuav kom nkag siab txog qhov tseem ceeb ntawm cov thev naus laus zis no, kev nkag siab tseem ceeb ntawm qhov attosecond txhais li cas yog qhov tseem ceeb heev. Ib qho attosecond sawv cev rau ib chav feeb ntawm lub sijhawm, tsim ib billionth ntawm ib billionth ntawm ib vib nas this hauv cov ntsiab lus dav dav ntawm ib vib nas this. Yuav kom muab qhov no rau hauv kev xav, yog tias peb piv ib vib nas this rau lub roob siab, ib qho attosecond yuav zoo li ib lub noob xuab zeb nyob ntawm lub hauv paus ntawm lub roob. Hauv lub sijhawm luv luv no, txawm tias lub teeb tsis tuaj yeem hla qhov deb sib npaug rau qhov loj ntawm ib lub atom. Los ntawm kev siv attosecond lasers, cov kws tshawb fawb tau txais lub peev xwm tsis tau muaj dua los tshuaj xyuas thiab tswj cov dynamics ntawm electrons hauv cov qauv atomic, zoo li ib qho kev ua si qeeb qeeb hauv ib qho kev ua yeeb yaj kiab, yog li ntawd nkag mus rau hauv lawv qhov kev sib cuam tshuam.

Cov laser Attosecondsawv cev rau qhov kawg ntawm kev tshawb fawb dav dav thiab kev sib koom tes los ntawm cov kws tshawb fawb, uas tau siv cov ntsiab cai ntawm nonlinear optics los tsim ultrafast lasers. Lawv qhov kev tshwm sim tau muab rau peb nrog lub hauv paus tshiab rau kev soj ntsuam thiab kev tshawb nrhiav ntawm cov txheej txheem dynamic transpiring hauv atoms, molecules, thiab txawm tias electrons hauv cov khoom khov.

Yuav kom piav qhia txog qhov xwm txheej ntawm attosecond lasers thiab txaus siab rau lawv cov yam ntxwv tsis zoo sib piv rau cov lasers ib txwm muaj, nws yog qhov tseem ceeb kom tshawb nrhiav lawv pawg hauv "tsev neeg laser" dav dua. Kev faib tawm los ntawm wavelength tso attosecond lasers feem ntau nyob rau hauv qhov ntau ntawm ultraviolet mus rau mos X-ray zaus, qhia txog lawv cov wavelengths luv dua piv rau cov lasers ib txwm muaj. Hauv cov hom tso zis, attosecond lasers poob rau hauv pawg ntawm pulsed lasers, uas yog tus cwj pwm los ntawm lawv lub sijhawm luv luv. Txhawm rau kos ib qho piv txwv rau kev meej meej, ib tus tuaj yeem xav txog cov lasers txuas ntxiv mus zoo li lub teeb ci ntsa iab uas tawm lub teeb txuas ntxiv mus, thaum cov lasers pulsed zoo li lub teeb strobe, hloov pauv sai ntawm lub sijhawm ntawm lub teeb pom kev zoo thiab qhov tsaus ntuj. Hauv qhov tseem ceeb, attosecond lasers qhia txog tus cwj pwm pulsating hauv lub teeb pom kev zoo thiab qhov tsaus ntuj, tsis tau lawv txoj kev hloov pauv ntawm ob lub xeev transpires ntawm qhov zaus xav tsis thoob, ncav cuag lub nceeg vaj ntawm attoseconds.

Kev faib ua pawg ntxiv los ntawm lub zog tso cov lasers rau hauv cov brackets qis-zog, nruab nrab-zog, thiab siab-zog. Attosecond lasers ua tiav lub zog siab tshaj plaws vim lawv lub sijhawm luv luv heev, ua rau muaj lub zog siab tshaj plaws (P) - txhais tias yog qhov muaj zog ntawm lub zog ib chav sijhawm (P = W / t). Txawm hais tias cov pulses laser attosecond ib leeg yuav tsis muaj lub zog loj heev (W), lawv qhov luv luv ntawm lub sijhawm (t) muab rau lawv nrog lub zog siab tshaj plaws.

Hais txog cov kev siv, lasers siv tau rau ntau yam kev siv hauv kev lag luam, kev kho mob, thiab kev tshawb fawb. Attosecond lasers feem ntau pom lawv qhov chaw nyob hauv kev tshawb fawb txog kev tshawb fawb, tshwj xeeb tshaj yog hauv kev tshawb nrhiav cov xwm txheej uas hloov pauv sai hauv cov kev tshawb fawb txog physics thiab chemistry, muab lub qhov rais rau hauv lub ntiaj teb microcosmic cov txheej txheem hloov pauv sai.

Kev faib ua pawg los ntawm cov khoom siv laser qhia txog cov lasers ua cov roj lasers, cov khoom siv solid-state lasers, cov kua lasers, thiab cov semiconductor lasers. Kev tsim cov attosecond lasers feem ntau nyob ntawm cov roj laser media, siv cov teebmeem optical nonlinear los tsim cov harmonics siab.

Hauv kev xaus lus, attosecond lasers yog ib chav kawm tshwj xeeb ntawm cov lasers luv luv, uas txawv los ntawm lawv lub sijhawm luv luv, feem ntau ntsuas hauv attoseconds. Yog li ntawd, lawv tau dhau los ua cov cuab yeej tseem ceeb rau kev soj ntsuam thiab tswj cov txheej txheem dynamic ultrafast ntawm electrons hauv atoms, molecules, thiab cov khoom khov.

Cov Txheej Txheem Ua Kom Zoo Dua ntawm Attosecond Laser Generation

Cov thev naus laus zis laser Attosecond sawv ntawm qhov ua ntej ntawm kev tsim kho tshiab, khav txog cov xwm txheej nyuaj heev rau nws txoj kev tsim. Txhawm rau piav qhia txog qhov nyuaj ntawm kev tsim laser attosecond, peb pib nrog kev piav qhia luv luv ntawm nws cov hauv paus ntsiab lus, ua raws li cov lus piv txwv pom tseeb los ntawm kev paub txhua hnub. Cov neeg nyeem uas tsis paub txog qhov nyuaj ntawm cov physics cuam tshuam tsis tas yuav poob siab, vim tias cov lus piv txwv tom qab ntawd lub hom phiaj yog ua kom cov physics tseem ceeb ntawm attosecond lasers nkag tau yooj yim.

Cov txheej txheem tsim cov lasers attosecond feem ntau vam khom cov txheej txheem hu ua High Harmonic Generation (HHG). Ua ntej, ib lub teeb ntawm lub zog siab femtosecond (10^-15 vib nas this) laser pulses raug tsom mus rau cov khoom siv roj. Nws tsim nyog sau tseg tias femtosecond lasers, zoo li attosecond lasers, sib koom cov yam ntxwv ntawm kev muaj lub sijhawm luv luv thiab lub zog siab tshaj plaws. Nyob rau hauv kev cuam tshuam ntawm lub zog laser teb, cov electrons hauv cov roj atoms raug tso tawm ib ntus ntawm lawv cov nuclei atomic, nkag mus rau hauv lub xeev ntawm cov electrons dawb. Thaum cov electrons no oscillate teb rau lub teb laser, lawv thaum kawg rov qab mus rau thiab recombine nrog lawv niam txiv atomic nuclei, tsim cov xeev tshiab muaj zog siab.

Thaum lub sijhawm no, cov electrons txav mus rau qhov ceev heev, thiab thaum rov sib xyaw nrog cov nuclei atomic, lawv tso tawm lub zog ntxiv hauv daim ntawv ntawm cov pa phem harmonic siab, uas ua rau pom tias yog cov photons muaj zog siab.

Cov zaus ntawm cov photons tshiab no muaj zog heev yog cov lej sib npaug ntawm cov zaus laser thawj, tsim cov uas hu ua high-order harmonics, qhov twg "harmonics" txhais cov zaus uas yog cov lej sib npaug ntawm cov zaus thawj. Yuav kom ua tiav cov lasers attosecond, nws tsim nyog los lim thiab tsom cov harmonics siab no, xaiv cov harmonics tshwj xeeb thiab tsom lawv mus rau hauv qhov chaw tseem ceeb. Yog tias xav tau, cov txheej txheem nias pulse tuaj yeem ua kom luv dua lub sijhawm pulse, ua rau cov pulses luv luv hauv qhov ntau ntawm attosecond. Pom tseeb, kev tsim cov lasers attosecond yog ib qho txheej txheem zoo thiab ntau yam, xav tau qib siab ntawm kev txawj ntse thiab cov khoom siv tshwj xeeb.

Yuav kom piav qhia txog cov txheej txheem nyuaj no, peb muab ib qho piv txwv piv txwv uas siv rau hauv cov xwm txheej txhua hnub:

Cov Teeb Meem Laser Femtosecond Uas Muaj Zog Heev:

Xav txog seb puas muaj lub catapult muaj zog heev uas muaj peev xwm pov pob zeb sai sai nrog qhov ceev loj heev, zoo li lub luag haujlwm ntawm cov pulses laser femtosecond siab.

Cov Khoom Siv Gas:

Xav txog ib lub pas dej uas nyob ntsiag to uas yog lub cim ntawm cov khoom siv roj, qhov twg txhua tee dej sawv cev rau ntau lub atoms roj. Qhov kev ua ntawm kev thawb cov pob zeb mus rau hauv lub cev dej no zoo ib yam li qhov cuam tshuam ntawm cov pulses femtosecond laser siab rau cov khoom siv roj.

Kev Txav Mus Los thiab Kev Sib Sau Ua Ke ntawm Cov Hluav Taws Xob (Kev Hloov Pauv Lub Cev):

Thaum cov femtosecond laser pulses cuam tshuam rau cov roj atoms hauv cov khoom siv roj, ntau cov electrons sab nraud tau raug txhawb nqa ib ntus rau lub xeev uas lawv tawm ntawm lawv cov atomic nuclei, tsim ib lub xeev zoo li plasma. Thaum lub zog ntawm lub cev txo qis (vim tias cov laser pulses yog inherently pulsed, muaj cov sijhawm ntawm kev tso tseg), cov electrons sab nraud no rov qab mus rau lawv qhov chaw nyob ze ntawm cov atomic nuclei, tso tawm cov photons muaj zog siab.

Kev Tsim Harmonic Siab:

Xav txog txhua zaus uas ib tee dej poob rov qab rau ntawm lub pas dej, nws tsim cov ripples, zoo li cov harmonics siab hauv attosecond lasers. Cov ripples no muaj cov zaus thiab qhov loj dua li cov ripples thawj zaug uas tshwm sim los ntawm lub zog laser femtosecond thawj zaug. Thaum lub sijhawm HHG, lub teeb laser muaj zog, zoo li cov pob zeb pov tseg tas li, ci lub hom phiaj roj, zoo li lub pas dej saum npoo av. Lub zog laser no ua rau cov electrons hauv cov roj, zoo li cov ripples, tawm ntawm lawv cov atoms niam txiv thiab tom qab ntawd rub lawv rov qab. Txhua zaus uas ib lub electron rov qab mus rau lub atom, nws tso tawm lub teeb laser tshiab nrog cov zaus siab dua, zoo li cov qauv ripple nyuaj dua.

Kev lim thiab kev tsom mus rau:

Kev sib xyaw ua ke tag nrho cov teeb laser tshiab no ua rau muaj ntau yam xim (zaus lossis wavelengths), qee qhov ntawm cov no tsim cov laser attosecond. Txhawm rau cais cov qhov loj me thiab zaus tshwj xeeb, koj tuaj yeem siv cov lim tshwj xeeb, zoo li xaiv cov ripples xav tau, thiab siv lub iav loj kom tsom lawv rau thaj chaw tshwj xeeb.

Kev nias lub plawv dhia (yog tias tsim nyog):

Yog tias koj lub hom phiaj xav kom cov ripples nthuav dav sai dua thiab luv dua, koj tuaj yeem ua kom lawv nthuav dav sai dua siv cov cuab yeej tshwj xeeb, txo lub sijhawm uas txhua lub ripple kav ntev. Kev tsim cov attosecond lasers cuam tshuam nrog kev sib koom ua ke ntawm cov txheej txheem. Txawm li cas los xij, thaum tawg thiab pom, nws yuav nkag siab ntau dua.