Ọganihu na oke ultravioletteknụzụ isi iyi
N'ime afọ ndị na-adịbeghị anya, ultraviolet dị elu na-emekọ ihe ọnụ adọtala mmasị dị ukwuu n'ọhịa nke electron dynamics n'ihi ịdị n'otu ha siri ike, oge pulse dị mkpirikpi na ike foton dị elu, ma ejiri ya mee ihe n'ọmụmụ ihe ngosi dị iche iche na ihe ngosi. Site na mmepe nke teknụzụ, nke aìhè isi iyina-etolite n'ụzọ dị elu ugboro ugboro ugboro ugboro, photon flux dị elu, ike photon dị elu na obosara usu dị mkpụmkpụ. Ọganihu a abụghị naanị na-ebuli mkpebi nha nke isi iyi ọkụ ultraviolet dị oke egwu, kamakwa na-enye ohere ọhụrụ maka usoro mmepe teknụzụ n'ọdịnihu. Ya mere, ọmụmụ ihe omimi na nghọta nke nkwughachi ugboro ugboro oke ọkụ ultraviolet dị oke mkpa maka ịmụta na itinye teknụzụ na-egbu egbu.
Maka nha eletrọnịkị spectroscopy na femtosecond na attosecond oge akpịrịkpa, ọnụ ọgụgụ ihe omume ndị a tụrụ n'otu ọkụ anaghị ezughị oke, na-eme ka isi mmalite ọkụ na-emegharị obere oge ezughi oke iji nweta ọnụ ọgụgụ a pụrụ ịdabere na ya. N'otu oge ahụ, isi iyi ọkụ nwere obere flux photon ga-ebelata ogo mgbama na mkpọtụ nke onyonyo onyonyo n'oge obere mkpughe. Site na nchọgharị na nnwale na-aga n'ihu, ndị nchọpụta emela ọtụtụ nkwalite na njikarịcha mkpụrụ na nhazi nnyefe nke ọkụ ọkụ ultraviolet dị elu ugboro ugboro ugboro ugboro. A na-eji teknụzụ nyocha ihe nleba anya dị elu jikọtara ya na isi iyi ọkụ ultraviolet ugboro ugboro ugboro ugboro iji nweta nha nkenke nke usoro ihe yana usoro ike elektrọnik.
Ngwa nke isi iyi ọkụ ultraviolet dị oke egwu, dị ka nha eletrọnịkị spectroscopy (ARPES), chọrọ ọkụ nke oke ọkụ ultraviolet iji mee ka nlele ahụ pụta ìhè. The electrons n'elu nke sample na-enwe obi ụtọ na-aga n'ihu na steeti site oké ultraviolet ìhè, na kinetic ike na emission Angle nke photoelectrons nwere band Ọdịdị ozi nke sample. Onye nyocha eletrọn nwere ọrụ mkpebi nke Angle na-enweta fotoelectrons radiated wee nweta nhazi band n'akụkụ band valence nke sample. N'ihi na obere ugboro ugboro ugboro oké ultraviolet ìhè isi iyi, n'ihi na ya otu usu nwere ọnụ ọgụgụ buru ibu nke photons, ọ ga-akpali a ọnụ ọgụgụ buru ibu nke photoelectrons n'elu sample n'ime obere oge, na Coulomb mmekọrịta ga-eme ka a dị oké njọ gbasaa nkesa nke photoelectron kinetic ike, nke a na-akpọ ohere ụgwọ mmetụta. Iji belata mmetụta nke mmetụta ụgwọ ohere ohere, ọ dị mkpa iji belata photoelectrons dị na nke ọ bụla pulse mgbe ị na-ejigide photon flux mgbe niile, ya mere ọ dị mkpa iji kwọọ ụgbọ ala.laserna ugboro ugboro ugboro ugboro iji mepụta ọkụ ultraviolet dị oke egwu na ugboro ugboro ugboro ugboro.
Teknụzụ ọgbara ọhụrụ nke Resonance na-achọpụta ọgbọ nke nkwekọ dị elu na ugboro ugboro ugboro ugboro
Iji nweta oke ọkụ ọkụ ultraviolet nke nwere nkwughachi ihe ruru 60 MHz, ndị otu Jones na Mahadum British Columbia dị na United Kingdom rụrụ usoro nkwekọ dị elu n'ọgbọ femtosecond resonance enhancement cavity (fsEC) iji nweta isi iyi ọkụ ultraviolet bara uru ma tinye ya n'ọrụ na-edozi oge angular-spectroscopy electron.S. Isi iyi ọkụ ahụ nwere ike ịnyefe foton flux karịa 1011 foton nọmba kwa sekọnd na otu harmonic na nkwughachi nke 60 MHz na oke ike nke 8 ruo 40 eV. Ha jiri sistemu laser ytterbium-doped fiber laser dị ka isi mmalite mkpụrụ maka fsEC, yana njirimara pulse a na-achịkwa site na nhazi sistemu laser ahaziri iji belata mkpọtụ ihe mkpuchi ụgbọ elu (fCEO) ma nọgide na-enwe àgwà mkpakọ pulse dị mma na njedebe nke yinye ampilifaya. Iji nweta nkwalite resonance kwụsiri ike n'ime fsEC, ha na-eji loops njikwa servo atọ maka njikwa nzaghachi, na-eme ka nkwụsi ike na-arụ ọrụ na ogo nnwere onwe abụọ: oge njem okirikiri nke ịgba ígwè pulse n'ime fsEC dabara na oge ọkụ ọkụ laser, na ngbanwe oge nke onye na-ebu ọkụ eletrik n'ihe gbasara envelopu pulse (ya bụ, akpa ụgbọ ala).
Site na iji krypton gas dị ka gas na-arụ ọrụ, ndị otu nyocha nwetara ọgbọ nke harmonics dị elu na fsEC. Ha mere nha Tr-ARPES nke graphite wee hụ ọkụ ọkụ ngwa ngwa yana nchikota ngwa ngwa nke ndị eletrọn na-enweghị obi ụtọ, yana ike nke steeti ndị na-enweghị thermal ozugbo nwere obi ụtọ n'akụkụ ọkwa Fermi n'elu 0.6 eV. Isi iyi ọkụ a na-enye ngwá ọrụ dị mkpa maka ịmụ ihe nhazi eletrọnịkị nke ihe mgbagwoju anya. Otú ọ dị, ọgbọ nke harmonics dị elu na fsEC nwere nnukwu ihe a chọrọ maka ntụgharị uche, nkwụghachi ụgwọ mgbasa ozi, nhazi nke ọma nke ogologo oghere na mkpọchi mmekọrịta, nke ga-emetụta nnukwu mmụba nke oghere resonance. N'otu oge ahụ, nzaghachi na-adịghị ahụ anya nke plasma na ebe etiti oghere bụkwa ihe ịma aka. Ya mere, ugbu a, ụdị ọkụ a aghọbeghị ihe kachasị ultravioletelu harmonic ìhè isi iyi.
Oge nzipu: Eprel-29-2024