Esimemezelweni esibalulekile kusihlwa sangomhlaka-3 Okthoba 2023, kwadalulwa uMklomelo KaNobel kuFiziksi wonyaka ka-2023, kuqashelwa iminikelo evelele yososayensi abathathu abadlale indima ebalulekile njengabaphayona emkhakheni wobuchwepheshe be-attosecond laser.

Igama elithi "i-attosecond laser" livela esikalini sesikhathi esifushane kakhulu esisebenza kuso, ikakhulukazi ngokulandelana kwe-attoseconds, okuhambisana nemizuzwana eyi-10^-18. Ukuze kuqondwe ukubaluleka okujulile kwalolu buchwepheshe, ukuqonda okuyisisekelo kwalokho okushiwo yi-attosecond kubaluleke kakhulu. I-attosecond imelela njengeyunithi yesikhathi emfushane kakhulu, eyakha ingxenye eyodwa kwezigidigidi zengxenye yesigidigidi yomzuzwana ngaphakathi komongo obanzi womzuzwana owodwa. Ukuze sikubeke embonweni, uma singafanisa umzuzwana nentaba ende, i-attosecond ibingafana nohlamvu olulodwa lwesihlabathi olubekwe phansi kwentaba. Kulesi sikhathi esisheshayo, ngisho nokukhanya akukwazi ukunqamula ibanga elilingana nobukhulu be-athomu ngayinye. Ngokusebenzisa ama-attosecond lasers, ososayensi bathola ikhono elingakaze libonwe lokuhlola nokulawula amandla ayinkimbinkimbi ama-electron ngaphakathi kwezakhiwo ze-athomu, njengokuphindaphindwa kokuhamba kancane kohlaka ngohlaka ngokulandelana kwe-cinematic, ngaleyo ndlela bahlole ukusebenzisana kwawo.

Ama-laser e-Attosecondkumelela umvuthwandaba wocwaningo olunzulu kanye nemizamo ehlangene yososayensi, abaye basebenzisa izimiso ze-optics ezingezona eziqondile ukwenza ama-laser asheshayo. Ukufika kwabo kusinikeze indawo entsha yokubuka nokuhlola izinqubo eziguquguqukayo ezenzeka ngaphakathi kwama-athomu, ama-molecule, ngisho nama-electron ezintweni eziqinile.

Ukuze kucaciswe uhlobo lwama-laser e-attosecond futhi kuqashelwe izimfanelo zawo ezingavamile uma kuqhathaniswa nama-laser avamile, kubalulekile ukuhlola ukuhlukaniswa kwawo ngaphakathi "komndeni we-laser" obanzi. Ukuhlukaniswa ngobude be-wavelength kubeka ama-laser e-attosecond ikakhulukazi ngaphakathi kobubanzi bemvamisa ye-ultraviolet kuya kwe-X-ray ethambile, okubonisa ubude bawo obufushane kakhulu ngokungafani nama-laser avamile. Ngokuphathelene nezindlela zokukhipha, ama-laser e-attosecond awela ngaphansi kwesigaba sama-laser acindezelwe, abonakala ngobude bawo obufushane kakhulu be-pulse. Ukuze kudwetshwe ukufaniswa kokucaca, umuntu angacabanga ngama-laser agxiliwe njenge-continuous-wave afana ne-flashlight ekhipha ukukhanya okuqhubekayo, kuyilapho ama-laser acindezelwe efana nokukhanya kwe-strobe, okushintshana ngokushesha phakathi kwezikhathi zokukhanya nobumnyama. Empeleni, ama-laser e-attosecond abonisa ukuziphatha okushukumisayo ngaphakathi kokukhanya nobumnyama, kodwa ukuguquka kwawo phakathi kwalezi zimo ezimbili kwenzeka ngemvamisa emangalisayo, kufinyelela endaweni yama-attosecond.

Ukuhlukaniswa okwengeziwe ngamandla kubeka ama-laser kuma-bracket anamandla aphansi, anamandla aphakathi nendawo, kanye nanamandla aphezulu. Ama-laser e-Attosecond athola amandla aphezulu ngenxa yesikhathi sawo esifushane kakhulu sokushaya kwenhliziyo, okuholela kumandla aphezulu kakhulu (P) - achazwa njengokuqina kwamandla ngesikhathi seyunithi (P=W/t). Nakuba ama-pulse e-laser e-attosecond ngamanye engase angabi namandla amakhulu kakhulu (W), izinga lawo elifinyeziwe lesikhashana (t) liwanikeza amandla aphezulu kakhulu.

Ngokuphathelene nezindawo zokusetshenziswa, ama-laser ahlanganisa ububanzi obuhlanganisa izinhlelo zokusebenza zezimboni, zezokwelapha, nezesayensi. Ama-laser e-Attosecond athola indawo yawo ngokuyinhloko emkhakheni wocwaningo lwesayensi, ikakhulukazi ekuhloleni izinto ezishintsha ngokushesha ngaphakathi kwezindawo zefiziksi nekhemistri, okunikeza ithuba lokufinyelela ezinqubweni ezisheshayo zamandla zomhlaba we-microcosmic.

Ukuhlukaniswa ngezigaba nge-laser medium kuveza ama-laser njenge-gas lasers, i-solid-state lasers, i-liquid lasers, kanye ne-semiconductor lasers. Ukukhiqizwa kwama-attosecond lasers ngokuvamile kuncike ku-gas laser media, kusizakale ngemiphumela ye-optical engeyona i-linear ukuze kuvele ama-harmonics aphezulu.

Ekufinyezweni, ama-laser e-attosecond akha isigaba esiyingqayizivele sama-laser e-short-pulse, ahlukaniswa ubude bawo obufushane kakhulu be-pulse, obuvame ukulinganiswa ngama-attosecond. Ngenxa yalokho, abe ngamathuluzi abalulekile okubuka nokulawula izinqubo ezishintshashintshayo ezisheshayo zama-electron ngaphakathi kwama-athomu, ama-molecule, nezinto eziqinile.

Inqubo Ecacile Yokukhiqizwa Kwe-Laser Ye-Attosecond

Ubuchwepheshe be-laser ye-Attosecond buhamba phambili ekusungulweni kwesayensi, buzigqaja ngezimo eziqinile nezithakazelisayo zokukhiqizwa kwayo. Ukuze sicacise ubunzima bokukhiqizwa kwe-laser ye-attosecond, siqala ngokuchaza kafushane izimiso zayo eziyisisekelo, kulandelwe izingathekiso ezicacile ezithathwe kokuhlangenwe nakho kwansuku zonke. Abafundi abangawazi kahle ubunzima be-physics efanele akudingeki baphelelwe yithemba, njengoba izingathekiso ezilandelayo zihlose ukwenza i-physics eyisisekelo ye-laser ye-attosecond itholakale kalula.

Inqubo yokukhiqiza ama-laser e-attosecond incike kakhulu enkambisweni eyaziwa ngokuthi i-High Harmonic Generation (HHG). Okokuqala, umsebe wama-laser pulses e-femtosecond anamandla aphezulu (imizuzwana eyi-10^-15) ugxile kakhulu ezintweni eziqondiwe yigesi. Kubalulekile ukuqaphela ukuthi ama-laser e-femtosecond, afana nama-laser e-attosecond, abelana ngezici zokuba nezikhathi zokushaya ezimfushane kanye namandla aphezulu. Ngaphansi kwethonya lensimu ye-laser enamandla, ama-electron angaphakathi kwama-athomu egesi akhululwa okwesikhashana kuma-nuclei awo e-athomu, angene okwesikhashana esimweni sama-electron akhululekile. Njengoba la ma-electron eshintshashintsha ngenxa yensimu ye-laser, ekugcineni abuyela futhi ahlangane nama-athomu awo ayinhloko, adale izimo ezintsha zamandla aphezulu.

Phakathi nale nqubo, ama-electron ahamba ngesivinini esiphezulu kakhulu, futhi lapho ehlanganiswa ne-nuclei ye-athomu, akhipha amandla engeziwe ngesimo sokukhishwa okuphezulu kwe-harmonic, okubonakala njengama-photon anamandla aphezulu.

Ama-frequency ala ma-photon anamandla aphezulu asanda kukhiqizwa ayi-integer multiples ye-laser frequency yokuqala, akha lokho okubizwa ngokuthi ama-harmonics e-oda eliphezulu, lapho igama elithi "ama-harmonics" lisho ama-frequency ayi-integral multiples ye-frequency yokuqala. Ukuze uthole ama-laser e-attosecond, kuyadingeka ukuhlunga nokugxila la ma-harmonics e-oda eliphezulu, ukhethe ama-harmonics athile bese uwagxilisa endaweni eqondile. Uma uthanda, amasu okucindezela i-pulse angafinyeza isikhathi sokushaya kwenhliziyo, aveze ama-pulse amafushane kakhulu ebangeni le-attosecond. Ngokusobala, ukukhiqizwa kwama-laser e-attosecond kwakha inqubo eyinkimbinkimbi nenezici eziningi, edinga izinga eliphezulu lobuchwepheshe kanye nemishini ekhethekile.

Ukuze sicacise le nqubo eyinkimbinkimbi, sinikeza ukufana okungokomfanekiso okusekelwe ezimweni zansuku zonke:

Ama-Laser Pulses e-Femtosecond Anamandla Aphezulu:

Cabanga nje une-catapult enamandla kakhulu ekwazi ukuphonsa amatshe ngokushesha ngesivinini esikhulu, njengendima edlalwa ama-laser pulses e-femtosecond anamandla amakhulu.

Izinto Eziqondiwe Ezinegesi:

Cabanga ngamanzi athule afanekisela izinto eziqondiwe zegesi, lapho ithonsi ngalinye lamanzi limelela khona ama-athomu amaningi egesi. Isenzo sokuphonsa amatshe kulo mzimba wamanzi sifana nomthelela wama-laser pulses e-femtosecond anamandla aphezulu ezintweni eziqondiwe zegesi.

Ukunyakaza kwe-Electron kanye nokuhlanganiswa kabusha (Ukuguqulwa Okubizwa Ngokwemvelo):

Lapho ama-laser pulse e-femtosecond ethinta ama-athomu egesi ngaphakathi kwezinto eziqondiwe zegesi, inani elikhulu lama-electron angaphandle livuselelwa okwesikhashana esimweni lapho lisuka khona kuma-athomu awo, lakha isimo esifana ne-plasma. Njengoba amandla esistimu encipha kamuva (njengoba ama-laser pulse evuselelwa ngokwemvelo, anezikhawu zokuma), lawa ma-electron angaphandle abuyela eduze kwawo nama-athomu, ekhipha ama-photon anamandla aphezulu.

Isizukulwane Esiphezulu Se-Harmonic:

Cabanga isikhathi ngasinye lapho ithonsi lamanzi liwela ebusweni bechibi, lidala ama-ripple, afana kakhulu nama-harmonics aphezulu kuma-laser e-attosecond. La ma-ripple anemvamisa ephezulu kanye nama-amplitude kunama-ripple okuqala abangelwa yi-primary femtosecond laser pulse. Ngesikhathi senqubo ye-HHG, umsebe we-laser onamandla, ofana nokuphonsa amatshe njalo, ukhanyisa ithagethi yegesi, efana nobuso bechibi. Le nsimu ye-laser enamandla isunduza ama-electron kugesi, afana nama-ripple, kude nama-athomu awo okuqala bese ewadonsa emuva. Isikhathi ngasinye lapho i-electron ibuyela ku-athomu, ikhipha umsebe we-laser omusha onemvamisa ephezulu, efana namaphethini e-ripple ayinkimbinkimbi kakhulu.

Ukuhlunga Nokugxila:

Ukuhlanganisa yonke le misebe ye-laser esanda kukhiqizwa kuveza ububanzi bemibala ehlukahlukene (amaza noma ubude bamaza), eminye yayo eyakha i-laser ye-attosecond. Ukuze uhlukanise ubukhulu namaza athile, ungasebenzisa isihlungi esikhethekile, njengokukhetha amaza afunwayo, bese usebenzisa ingilazi yokukhulisa ukuze uwagxilise endaweni ethile.

Ukucindezela Kwe-Pulse (uma kudingeka):

Uma uhlose ukusabalalisa ama-ripple ngokushesha nangokufushane, ungasheshisa ukusabalala kwawo usebenzisa idivayisi ekhethekile, unciphise isikhathi i-ripple ngayinye ehlala ngaso. Ukukhiqizwa kwama-laser e-attosecond kuhilela ukusebenzisana okuyinkimbinkimbi kwezinqubo. Kodwa-ke, uma kuhlukaniswa futhi kubonwa ngamehlo, kuba lula ukukuqonda.