Qhov tshwj xeeb ultrafast laser ntu ob

Tshwj xeeblaser ceev heevib feem ob

Kev tawg thiab kev nthuav dav ntawm lub plawv dhia: Kev ncua sij hawm ntawm pawg neeg
Ib qho ntawm cov teeb meem kev siv tshuab nyuaj tshaj plaws uas ntsib thaum siv ultrafast lasers yog tswj lub sijhawm ntawm cov ultra-short pulses pib tso tawm los ntawmlaserCov pulses ceev heev yog qhov yooj yim rau kev cuam tshuam lub sijhawm, uas ua rau cov pulses ntev dua. Qhov cuam tshuam no zuj zus tuaj thaum lub sijhawm ntawm thawj lub pulse luv dua. Txawm hais tias cov lasers ceev heev tuaj yeem tso tawm cov pulses nrog lub sijhawm ntawm 50 vib nas this, lawv tuaj yeem ua kom loj dua hauv lub sijhawm los ntawm kev siv daim iav thiab lub lens los xa cov pulse mus rau qhov chaw, lossis txawm tias tsuas yog xa cov pulse los ntawm huab cua.

Qhov kev cuam tshuam lub sijhawm no yog ntsuas siv kev ntsuas hu ua pawg qeeb dispersion (GDD), tseem hu ua thib ob-txheej txheem dispersion. Qhov tseeb, kuj tseem muaj cov lus hais siab dua-txheej txheem dispersion uas yuav cuam tshuam rau lub sijhawm faib ntawm ultrafart-laser pulses, tab sis hauv kev xyaum, nws feem ntau txaus los tshuaj xyuas qhov cuam tshuam ntawm GDD. GDD yog tus nqi nyob ntawm zaus uas yog linearly proportional rau qhov tuab ntawm ib yam khoom. Cov khoom siv kis xws li lens, qhov rai, thiab cov khoom siv feem ntau muaj cov nqi GDD zoo, uas qhia tau tias thaum cov pulses compressed tuaj yeem muab cov khoom siv kis ntev dua li cov uas tso tawm los ntawmcov tshuab laserCov khoom uas muaj zaus qis dua (piv txwv li, cov wavelengths ntev dua) kis tau sai dua li cov khoom uas muaj zaus siab dua (piv txwv li, cov wavelengths luv dua). Thaum lub pulse hla dhau ntau dua thiab ntau dua cov khoom, cov wavelength hauv lub pulse yuav txuas ntxiv mus ntxiv thiab ntxiv mus rau lub sijhawm. Rau lub sijhawm luv dua ntawm lub pulse, thiab yog li ntawd cov bandwidths dav dua, qhov cuam tshuam no yog qhov ua rau muaj kev cuam tshuam loj heev thiab tuaj yeem ua rau lub sijhawm pulse distortion.

Cov ntawv thov laser ceev heev
kev ntsuas spectroscopy
Txij li thaum muaj cov khoom siv laser ceev heev, spectroscopy tau yog ib qho ntawm lawv cov chaw siv tseem ceeb. Los ntawm kev txo lub sijhawm pulse mus rau femtoseconds lossis txawm tias attoseconds, cov txheej txheem dynamic hauv physics, chemistry thiab biology uas keeb kwm tsis yooj yim sua kom pom tam sim no tuaj yeem ua tiav. Ib qho ntawm cov txheej txheem tseem ceeb yog kev txav mus los ntawm atomic, thiab kev soj ntsuam ntawm kev txav mus los ntawm atomic tau txhim kho kev nkag siab txog kev tshawb fawb ntawm cov txheej txheem tseem ceeb xws li kev co molecular, kev sib cais molecular thiab kev hloov pauv zog hauv cov protein photosynthetic.

kev thaij duab ntawm lub cev
Cov lasers ultrafast uas muaj zog tshaj plaws txhawb nqa cov txheej txheem nonlinear thiab txhim kho kev daws teeb meem rau kev thaij duab biological, xws li multi-photon microscopy. Hauv lub kaw lus multi-photon, txhawm rau tsim kom muaj lub teeb liab nonlinear los ntawm cov khoom siv biological lossis lub hom phiaj fluorescent, ob lub photons yuav tsum sib tshooj hauv qhov chaw thiab lub sijhawm. Lub tshuab nonlinear no txhim kho kev daws teeb meem ntawm kev thaij duab los ntawm kev txo cov teeb liab fluorescence keeb kwm yav dhau los uas ua rau muaj kev cuam tshuam rau kev kawm ntawm cov txheej txheem ib-photon. Lub keeb kwm yav dhau los ntawm lub teeb liab yooj yim tau piav qhia. Thaj chaw me me ntawm lub tshuab microscope multiphoton kuj tiv thaiv kev lom phototoxicity thiab txo qhov kev puas tsuaj rau cov qauv.

Daim Duab 1: Ib daim duab piv txwv ntawm txoj kev teeb pom kev hauv kev sim siv lub tshuab microscope ntau lub photon

Kev ua cov khoom siv laser
Cov khoom siv laser ceev ceev kuj tau hloov pauv laser micromachining thiab cov khoom siv ua vim yog txoj hauv kev tshwj xeeb uas ultrashort pulses cuam tshuam nrog cov khoom siv. Raws li tau hais ua ntej, thaum tham txog LDT, lub sijhawm ultrafast pulse yog sai dua li lub sijhawm ntawm kev sib kis cua sov mus rau hauv lub lattice ntawm cov khoom siv. Ultrafast lasers tsim cov cheeb tsam cuam tshuam cua sov me dua licov lasers pulsed nanosecond, ua rau qhov kev txiav tsawg dua thiab kev siv tshuab kom raug dua. Lub hauv paus ntsiab lus no kuj siv tau rau kev siv kho mob, qhov twg qhov kev txiav ultrafart-laser kom raug dua pab txo qhov kev puas tsuaj rau cov ntaub so ntswg ib puag ncig thiab txhim kho kev paub ntawm tus neeg mob thaum phais laser.

Attosecond pulses: yav tom ntej ntawm ultrafast lasers
Raws li kev tshawb fawb txuas ntxiv mus rau kev txhim kho ultrafast lasers, cov teeb pom kev tshiab thiab zoo dua nrog lub sijhawm luv dua ntawm lub zog tau raug tsim. Txhawm rau kom nkag siab txog cov txheej txheem lub cev sai dua, ntau tus kws tshawb fawb tab tom tsom mus rau kev tsim cov attosecond pulses - txog li 10-18 s hauv qhov ntau ntawm ultraviolet (XUV) wavelength. Attosecond pulses tso cai rau kev taug qab ntawm kev txav mus los ntawm electron thiab txhim kho peb txoj kev nkag siab ntawm cov qauv hluav taws xob thiab quantum mechanics. Txawm hais tias kev koom ua ke ntawm XUV attosecond lasers rau hauv cov txheej txheem kev lag luam tseem tsis tau ua tiav zoo, kev tshawb fawb thiab kev nce qib hauv thaj teb yuav luag thawb cov thev naus laus zis no tawm ntawm chav kuaj thiab mus rau hauv kev tsim khoom, zoo li tau ua rau femtosecond thiab picosecond.cov chaw laser.