01 Daim Ntawv Qhia
Optical nyias zaj duab xis (ib zaug / ntau- txheej txheej lossis gratings) yog siv dav hauv cov duab, laser systems, cov cuab yeej kho mob thiab aerospace. Hom-locking thiab chirped pulse amplification (CPA) cov tswv yim tsav picosecond/femtosecond ultrafast lasers, txawm hais tias nthuav kev siv xws li cov khoom siv vim lub siab ncov siab, kuj ua rau laser-vim kev puas tsuaj vim tsis yog -thermal photon{5}}electron interactions, etc. ib qho tseem ceeb limiting yam rau lifespan ntawm optical Cheebtsam. Hlau zaj duab xis gratings, nrog rau lawv broad reflectivity, yog ib qho tseem ceeb nyob rau hauv scenarios xws li CPA laser pulse compression, tab sis cov kev tshawb fawb uas twb muaj lawm tsis tau kom meej soj ntsuam cov kev sib raug zoo ntawm mem tes ntev (tshwj xeeb tshaj yog cov ntsiab lus nyob ze rau qhov tsawg kawg nkaus kev puas tsuaj), ntau pulses thiab kev puas tsuaj pib, los yog tsis txaus txiav txim siab lub sij hawm ntawm lub sij hawm hloov ntawm cov khoom nyob rau hauv lub zos electric teb. Yog li, qhov kev tshawb fawb no, los ntawm kev suav cov theoretical thiab kev sim, tshawb xyuas cov txheej txheem kev puas tsuaj ntawm txhuas zaj duab xis gratings (AMG) nyob rau hauv 2-15 ps picosecond laser irradiation, txhais cov kev puas tsuaj raws li qhov tsawg kawg nkaus laser fluence uas induces mus tas li morphological hloov, thaum lub 'cumulative effect' hais txog cov thermal hloov pauv los ntawm cov khoom siv hluav taws xob los yog cov khoom siv hluav taws xob rov ua dua.
02 Phau Ntawv Qhia Tag Nrho
Txoj kev tshawb no tsom mus rau AMG, txheeb xyuas lub sijhawm pulse ntawm picosecond lasers thiab cov txiaj ntsig kev puas tsuaj ntawm ntau lub pulses: Ua ntej, kev sib txuas ua ke nruj heev -wave analysis (RCWA) yog siv los simulate lub zog hluav taws xob hauv cheeb tsam kev faib tawm, txheeb xyuas cov grating ridges raws li qhov chaw tsis muaj zog tshaj plaws; ces, ob- kub qauv (TTM) characterizes lub ultrafast dynamics ntawm electrons thiab lattices, ua ke nrog txhuas tsis xws li latent tshav kub ntawm fusion, los kwv yees ib zaug -mem tes thiab multi- mem tes puas thresholds; kev sim, lub platform nrog lub sijhawm tiag tiag - lub sijhawm ntsuas kev ntsuas tau teeb tsa los ntsuas qhov kev puas tsuaj pib siv 2-15 ps tunable mem tes dav lasers, nrhiav qhov qis tshaj AMG kev puas tsuaj ntawm 10 ps (tus nqi sim 0.0705 J / cm²), thaum siv 1 krad pulse repetition 10 kHz Kev sim, nws tau pom tias qhov kev puas tsuaj loj zuj zus zuj zus nrog cov mem tes ntau ntxiv (poob rau 0.0346 J / cm² ntawm 1000 pulses), thiab kev puas tsuaj morphology (ablation, spattering, thiab lwm yam) ua rau cov pulses ntau zuj zus. Lub hauv paus ntawm txoj kev tshawb no yog tsim kom muaj kev sib raug zoo ntawm cov mem tes tsis muaj (pulse width, naj npawb) thiab AMG kev puas tsuaj, muab theoretical thiab sim kev txhawb nqa rau kev txhim kho laser-resistant optical coatings.
03 Graphical Analysis
Daim duab 1 intuitively qhia tau hais tias lub zog tseem ceeb ntawm cov txheej txheem ntawm kev sib cuam tshuam ntawm picosecond laser thiab txhuas zaj duab xis grating (AMG). Raws li pom, thaum lub laser ultrafast yog tshwm sim, cov dawb electrons nyob rau hauv cov hlau ua ntej sai sai nqus photon zog thiab zoo siab heev, tsim ib tug high - kub electron system; Tom qab ntawd, cov electrons zoo siab hloov lub zog mus rau lub lattice ib kauj ruam dhau los ntawm electron-phonon coupling thiab phonon-phonon scattering txheej txheem, thaum kawg ua rau kev hloov pauv hauv lattice kub. Cov txheej txheem no rhuav tshem cov thermal sib npaug ntawm cov hluav taws xob thiab cov lattice thiab yog lub zog tseem ceeb ntawm laser- ntxias kev puas tsuaj, muab lub cev lub cev rau kev tsim kho tom ntej ntawm ob- qauv kub (TTM).
Daim duab 2, raws li kev sib koom ua ke nruj heev-wave tsom (RCWA), qhia tau hais tias ntawm lub wavelength ntawm 1030 nm, qhov hluav taws xob siv hluav taws xob yog siab dua ntawm cov grating ridges, tsim "kub chaw" uas qhia txog qhov yuav pib cov ntsiab lus ntawm kev puas tsuaj. AMG kis tau tus mob, xav txog, thiab nqus spectra qhia tau hais tias nce lub sij hawm grating txhim kho lub zog nqus ntawm cov wavelengths sib txawv, ua rau muaj kev pheej hmoo ntawm cov khoom puas. SEM cov duab qhia pom kev puas tsuaj ntawm AMG lub kaum sab xis, ua raws li qhov chaw hluav taws xob "kub" qhov chaw, ua pov thawj qhov tseeb ntawm RCWA simulations.
Daim duab 3 quantifies lub evolution ntawm electron thiab lattice kub nyob rau hauv AMG nyob rau hauv picosecond laser raug siv ib tug ob- kub qauv: ntawm ib tug 10 ps mem tes dav, thaum lub laser zog ceev mus txog 0.076 J / cm², lub lattice kub nce mus rau lub melting point 3 ntawm txhuas (semulated) ib zaug -pulse puas pib rau 10 ps; ntawm lub zog ruaj khov, lub ncov hluav taws xob kub rau 2 ps luv mem tes yog siab dua li ntawd rau 15 ps ntev mem tes (raws li luv pulses tso lub zog sai dua thiab mloog zoo electron zog); nyob rau hauv 10 ps mem tes dav nrog 1 kHz repetition tus nqi, qhov kev puas tsuaj tom qab 10 pulses poob mus rau 0.0598 J / cm² vim thermal tsub zuj zuj, uas yog qis dua ib zaug -mem tes pib.
Hauv daim duab 4, kev teeb tsa kev sim ua tiav kev tswj hwm ntawm laser tsis thiab tiag- lub sijhawm soj ntsuam kev puas tsuaj los ntawm lub zog tswj module tsim los ntawm 2-15 ps tunable mem tes dav laser qhov chaw, ib nrab -wave phaj thiab ib lub polarizer, nrog rau qhov tseeb - lub sijhawm saib xyuas qhov system; qhov nkhaus qhia tau hais tias nyob rau hauv 2-15 ps mem tes dav dav, AMG kev puas tsuaj pib qis tshaj ntawm 10 ps (tus nqi sim 0.0705 J / cm², zoo ib yam nrog tus nqi simulated ntawm 0.076 J / cm²); subfigure (c) qhia tau hais tias nyob rau hauv ib tug 10 ps mem tes dav, raws li tus naj npawb ntawm pulses nce los ntawm 1 mus rau 1000, lub AMG kev puas tsuaj cheeb tsam maj mam nthuav thiab cov khoom splattering yuav loj zuj zus, kom meej meej reflecting lub multipulse tsub zuj zuj nyhuv.
Xaus:
Txoj kev tshawb no sib txuas txoj kev xav (RCWA + TTM) thiab cov kev sim kom paub meej qhov kev puas tsuaj ntawm AMG nyob rau hauv picosecond lasers: RCWA txheeb xyuas cov kab ridges raws li qhov chaw tsis muaj zog, TTM zoo simulates electron -lattice dynamics los kwv yees kev puas tsuaj rau qhov pib, thiab kev sim paub meej tias 10 qhov kev puas tsuaj los ntawm qhov tsawg tshaj plaws ntawm cov teebmeem electron- phonon so, lattice thermal diffusion limitation, thiab ib ntus absorption). Muaj cov txiaj ntsig tseem ceeb hauv qab 1 kHz multi-pulse irradiation, nrog rau qhov kev puas tsuaj tsawg zuj zus thiab kev puas tsuaj morphological zuj zus ntxiv raws li cov pulses nce ntxiv. Txawm hais tias TTM tsis ua tiav tag nrho cov txiaj ntsig kev sim vim yog tsis quav ntsej cov khoom tsis xws luag, theem hloov pauv hloov pauv (xws li evaporation), thiab cov teebmeem ntawm cov neeg kho tshuab (xws li thermal stress), nws tseem muab ib qho kev sib koom ua ke rau kev sib koom ua ke ntawm cov yeeb yaj kiab hlau thiab ultrafast lasers. Cov kev tshawb pom no yog cov kev taw qhia tseem ceeb rau kev txhim kho lub durability ntawm siab -lub zog laser tshuab thiab precision optical Cheebtsam, tsim laser kev tiv thaiv nyob rau hauv aerospace thiab industrial laser ua, thiab muab pov thawj tseem ceeb rau optimizing cov ntaub ntawv thiab cov qauv ntawm laser{10}}resistant films.
