Eyodwai-laser ekhawulezayoinxalenye yokuqala
Iimpawu ezizodwa ze-ultrafastiilaser
I-ultra-short pulse duration of ultrafast lasers inika ezi nkqubo iipropathi ezizodwa ezohlula kwiilaser ze-long-pulse okanye i-continuous-wave (CW). Ukuze uvelise i-pulse emfutshane, i-bandwidth ye-spectrum ebanzi iyafuneka. Ubume be-pulse kunye ne-wavelength esembindini imisela ubuncinci bobubanzi be-bandwidth efunekayo ukuvelisa iipulse zobude bexesha elithile. Ngokuqhelekileyo, olu lwalamano luchazwe ngokwexesha lemveliso ye-bandwidth (TBP), ephuma kumgaqo wokungaqiniseki. I-TBP yokubetha kweGaussian inikwa ngale fomula ilandelayo :TBPGaussian=ΔτΔν≈0.441
Δτ lixesha lokubetha kwentliziyo kwaye Δv ngumda wokujikeleza. Eyona nto, i-equation ibonisa ukuba kukho ubudlelwane obuphambeneyo phakathi kwe-spectrum bandwidth kunye nobude be-pulse, oku kuthetha ukuba njengoko ubude be-pulse buyancipha, i-bandwidth efunekayo ukuvelisa ukuba i-pulse yanda. Umzobo woku-1 ubonisa ubuncinci be-bandwidth efunekayo ukuxhasa amaxesha amaninzi ahlukeneyo epulse.
Umzobo 1: Ubuncinci be-bandwidth ye-spectral efunekayo ukuxhasaimithambo laserof 10 ps (green), 500 fs (bhlowu), kunye 50 fs (bomvu)
Imingeni yobuchwephesha yee-laser ezikhawulezayo
I-bandwidth ye-spectral ebanzi, amandla aphezulu, kunye nobude bexesha elifutshane le-laser ye-ultrafast kufuneka ilawulwe ngokufanelekileyo kwinkqubo yakho. Rhoqo, esinye sezona zisombululo zilula kule miceli mngeni kukuphuma okubanzi kweelaser. Ukuba uye wasebenzisa ngokuphambili i-pulse okanye i-laser-wave eqhubekayo kwixesha elidlulileyo, isitokhwe sakho esikhoyo samalungu okukhanya asinakukwazi ukubonakalisa okanye ukuhambisa i-bandwidth epheleleyo yee-ultrafast pulses.
Umda womonakalo weLaser
I-Ultrafast optics nayo ihluke kakhulu kwaye inzima kakhulu ukuhamba nge-laser umonakalo we-laser (LDT) xa kuthelekiswa nemithombo ye-laser eqhelekileyo. Xa i-optics ibonelelwai-nanosecond pulsed lasers, Amaxabiso e-LDT adla ngokulandelelana kwe-5-10 J/cm2. Kwi-ultrafast optics, amaxabiso alo bukhulu ayenzekanga, njengoko amaxabiso e-LDT kunokwenzeka ukuba abe ngokomyalelo we-<1 J/cm2, edla ngokusondela ku-0.3 J/cm2. Ukwahluka okubalulekileyo kwe-LDT amplitude phantsi kobude be-pulse eyahlukeneyo sisiphumo somonakalo we-laser osekelwe kubude be-pulse. Kuba lasers nanosecond okanye ngaphezului-pulsed lasers, eyona ndlela iphambili eyenza umonakalo kukufudumala kwe-thermal. Izinto zokwaleka kunye ne-substrate ye-izixhobo zamehlofunxa iifotoni zesiganeko kwaye uzifudumeze. Oku kunokukhokelela ekugqwethekeni kwe-crystal lattice yemathiriyeli. Ukwandiswa kobushushu, ukuqhekeka, ukunyibilika kunye noxinzelelo lwelattice zezona ndlela ziqhelekileyo zomonakalo wobushushu kweziimithombo laser.
Nangona kunjalo, kwii-lasers ze-ultrafast, ubude be-pulse ngokwawo bukhawuleza kunexesha lokudluliselwa kobushushu ukusuka kwi-laser ukuya kwi-lattice yezinto eziphathekayo, ngoko ke umphumo we-thermal awuyena nobangela uphambili womonakalo owenziwe nge-laser. Endaweni yoko, amandla aphezulu e-laser ye-ultrafast aguqula indlela yokulimala ibe yinkqubo engahambelaniyo efana ne-multi-photon absorption kunye ne-ionization. Kungenxa yoko le nto kungenakwenzeka ukuba unciphise nje ukulinganisa kwe-LDT ye-nanosecond pulse ukuya kwi-ultrafast pulse, kuba indlela yokulimala yomzimba yahlukile. Ke ngoko, phantsi kweemeko ezifanayo zokusetyenziswa (umzekelo, ubude bamaza, ixesha lokubetha kwentliziyo, kunye nesantya sokuphinda-phinda), isixhobo esibonayo esinomgangatho ophezulu ngokwaneleyo we-LDT siya kuba sesona sixhobo sibalaseleyo sokubona isicelo sakho. I-Optics evavanyiweyo phantsi kweemeko ezahlukeneyo ayimelanga ukusebenza kwangempela kwe-optics efanayo kwinkqubo.
Umzobo 1: Iinkqubo zokwenza umonakalo we-laser kunye nobude be-pulse eyahlukeneyo
Ixesha lokuposa: Jun-24-2024