Ama-pulse e-Attosecondkwembula izimfihlo zokulibaziseka kwesikhathi
Ososayensi e-United States, ngosizo lwe-attosecond pulses, baveze ulwazi olusha mayelanaumphumela we-photoelectric: iukukhishwa kwe-photoelectricUkulibaziseka kufinyelela kumasekhondi angu-700, isikhathi eside kakhulu kunalokho obekulindelwe ngaphambilini. Lolu cwaningo lwakamuva luphonsela inselelo amamodeli emfundiso akhona futhi lusiza ekuqondeni okujulile ukusebenzisana phakathi kwama-electron, okuholela ekuthuthukisweni kobuchwepheshe obufana nama-semiconductor namaseli elanga.
Umphumela we-photoelectric ubhekisela esimweni sokuthi lapho ukukhanya kukhanya ku-molecule noma i-athomu ebusweni bensimbi, i-photon ixhumana ne-molecule noma i-athomu bese ikhipha ama-electron. Lo mphumela awusona nje esinye sezisekelo ezibalulekile ze-quantum mechanics, kodwa futhi unomthelela omkhulu kwi-physics yesimanje, i-chemistry kanye nesayensi yezinto ezibonakalayo. Kodwa-ke, kulo mkhakha, lokho okubizwa ngokuthi isikhathi sokulibaziseka kwe-photoemission kube yisihloko esiphikisanayo, futhi amamodeli ahlukahlukene emfundiso ayichaze ngamazinga ahlukene, kodwa akukho ukuvumelana okuhlanganisiwe okwakhiwe.
Njengoba insimu yesayensi ye-attosecond ithuthuke kakhulu eminyakeni yamuva nje, leli thuluzi elivelayo linikeza indlela engakaze ibonwe yokuhlola umhlaba omncane. Ngokulinganisa ngokunembile izenzakalo ezenzeka ngezikali zesikhathi esifushane kakhulu, abacwaningi bayakwazi ukuthola ulwazi olwengeziwe mayelana nokuziphatha okuguquguqukayo kwezinhlayiya. Ocwaningweni lwakamuva, basebenzise uchungechunge lwama-pulse e-X-ray anamandla aphezulu akhiqizwa umthombo wokukhanya ohlangene eStanford Linac Center (SLAC), owahlala ingxenye eyodwa kweziyizigidigidi zomzuzwana (attosecond), ukuze benze ama-electron ayinhloko abe yi-ion futhi "akhiphe" i-molecule ejabule.
Ukuze bahlaziye kabanzi izindlela zala ma-electron akhishwe, basebenzise ama-excited ngamanyeukushaya kwe-laserukukala izikhathi zokukhishwa kwama-electron ngezindlela ezahlukene. Le ndlela yabavumela ukubala ngokunembile umehluko obalulekile phakathi kwezikhathi ezahlukene ezibangelwa ukusebenzisana phakathi kwama-electron, okuqinisekisa ukuthi ukubambezeleka kungafinyelela kuma-attosecond angu-700. Kubalulekile ukuqaphela ukuthi lokhu kutholwa akugcini nje ngokuqinisekisa eminye imibono yangaphambilini, kodwa futhi kuphakamisa imibuzo emisha, okwenza imibono efanele idinga ukuhlolwa kabusha nokubuyekezwa.
Ngaphezu kwalokho, lolu cwaningo luqokomisa ukubaluleka kokulinganisa nokuhumusha lokhu kubambezeleka kwesikhathi, okubalulekile ekuqondeni imiphumela yokuhlola. Ku-protein crystallography, i-medical imaging, kanye nezinye izinhlelo zokusebenza ezibalulekile ezihilela ukusebenzisana kwe-X-ray nezinto, le datha izoba yisisekelo esibalulekile sokwenza ngcono izindlela zobuchwepheshe kanye nokuthuthukisa ikhwalithi ye-imaging. Ngakho-ke, ithimba lihlela ukuqhubeka nokuhlola amandla kagesi ezinhlobo ezahlukene zama-molecule ukuze kwembulwe ulwazi olusha mayelana nokuziphatha kwe-elekthronikhi ezinhlelweni eziyinkimbinkimbi kakhulu kanye nobudlelwano bazo nesakhiwo sama-molecule, okubeka isisekelo sedatha esiqinile sokuthuthukiswa kobuchwepheshe obuhlobene esikhathini esizayo.
Isikhathi sokuthunyelwe: Septhemba-24-2024