Nā holomua i ka ʻenehana kumu kukui ultraviolet

ʻO nā holomua i ka ultraviolet loaʻenehana kumu māmā

I nā makahiki i hala iho nei, ua hoʻokipa nui ʻia nā kumu kumu harmonic kiʻekiʻe ultraviolet i ke kahua o ka dynamics electron ma muli o ko lākou coherence ikaika, ka lōʻihi o ka pulse a me ka ikehu photon kiʻekiʻe, a ua hoʻohana ʻia i nā haʻawina spectral a me nā kiʻi.Me ka holomua o ka ʻenehana, kēiakumu kukuike ulu nei i ke alapine o ka hana hou ʻana, ʻoi aku ka kiʻekiʻe o ka photon flux, ka ikehu photon kiʻekiʻe a me ka laulā puʻupuʻu pōkole.ʻAʻole wale kēia holomua i ka hoʻonā ana ʻana o nā kumu kukui ultraviolet loa, akā hāʻawi pū kekahi i nā mea hou no nā ʻano hoʻomohala ʻenehana e hiki mai ana.No laila, ʻo ka noiʻi hohonu a me ka hoʻomaopopo ʻana i ke kiʻekiʻe repetition frequency extreme ultraviolet light source he mea koʻikoʻi no ka haku a hoʻohana ʻana i ka ʻenehana ʻoki.

No nā ana electron spectroscopy ma ka femtosecond a me ka attosecond manawa unahi, ʻaʻole lawa ka helu o nā hanana i ana ʻia i ka kukuna hoʻokahi, no laila ʻaʻole lawa nā kumu kukui refrequency no ka loaʻa ʻana o nā ʻikepili hilinaʻi.I ka manawa like, ʻo ke kumu māmā me ka photon flux haʻahaʻa e hōʻemi i ka ratio signal-to-noise o ke kiʻi microscopic i loko o ka manawa hōʻike palena.Ma o ka ʻimi hoʻomau ʻana a me nā hoʻokolohua, ua hana nā mea noiʻi i nā hoʻomaikaʻi he nui i ka hoʻonui ʻana i ka hua a me ka hoʻolālā hoʻoili ʻana o ke kukui uila ultraviolet kiʻekiʻe.Ua hoʻohana ʻia ka ʻenehana loiloi spectral holomua i hui pū ʻia me ke kiʻekiʻe repetition frequency extreme ultraviolet light source no ka hoʻokō ʻana i ke ana kikoʻī kiʻekiʻe o ka hoʻolālā waiwai a me ke kaʻina hana uila uila.

ʻO nā noi o nā kumu kukui ultraviolet loa, e like me ke ana ʻana o ka angular resolved electron spectroscopy (ARPES), pono i kahi kukuna kukui ultraviolet loa e hoʻomālamalama i ka hāpana.ʻO nā electrons ma ka ʻili o ka hāpana e hauʻoli i ke kūlana hoʻomau e ke kukui ultraviolet loa, a ʻo ka ʻenekini kinetic a me ka hoʻokuʻu ʻana Angle o nā photoelectrons i loaʻa ka ʻike o ka hoʻolālā band o ka hāpana.E loaʻa i ka mea kālai uila me ka hana hoʻonā Angle i nā photoelectrons i hoʻomālamalama ʻia a loaʻa i ke ʻano hui ma kahi kokoke i ke kaula valence o ka hāpana.No ka haʻahaʻa repetition alapine (frequency repetition frequency extreme ultraviolet light source), no ka mea, he nui nā photon i loko o kona puʻupuʻu hoʻokahi, e hoʻohauʻoli ia i ka nui o nā photoelectrons ma ka ʻaoʻao hāpana i ka manawa pōkole, a ʻo ka pilina Coulomb e lawe mai i kahi ākea koʻikoʻi o ka puʻunaue. o ka ikehu kinetic photoelectron, ka mea i kapaia ka hopena o ke kau wahi.I mea e hōʻemi ai i ka hopena o ka hopena o ka uku o ka lewa, pono e hōʻemi i nā photoelectrons i loko o kēlā me kēia pulse me ka mālama ʻana i ka flux photon mau, no laila pono e hoʻokele i ka.laserme ke alapine repetition kiʻekiʻe e hana i ke kumu kukui ultraviolet loa me ke alapine repetition kiʻekiʻe.

Hoʻomaopopo ka ʻenehana hoʻonui i ka resonance i ka hoʻokumu ʻana o nā harmonics kiʻekiʻe ma MHz repetition frequency.
No ka loaʻa ʻana o kahi kumu kukui ultraviolet ʻoi loa me ka helu hou ʻana a hiki i 60 MHz, ua hana ka hui Jones ma ke Kulanui o British Columbia ma United Kingdom i ka hanauna harmonic kiʻekiʻe i loko o kahi femtosecond resonance enhancement cavity (fsEC) e hoʻokō i kahi hana kūpono. kumu kukui ultraviolet loa a hoʻohana ʻia i nā hoʻokolohua ʻano ʻike electron i hoʻoholo ʻia i ka manawa (Tr-ARPES).Hiki i ke kumu kukui ke hāʻawi i kahi kiʻi kiʻi kiʻi ʻoi aku ma mua o 1011 mau helu kiʻi i kēlā me kēia kekona me kahi harmonic hoʻokahi i ka helu hoʻopiʻi o 60 MHz ma ka laulā ikehu o 8 a 40 eV.Ua hoʻohana lākou i ka ytterbium-doped fiber laser system ma ke ʻano he kumu hua no fsEC, a hoʻomalu i nā hiʻohiʻona pulse ma o ka hoʻolālā ʻōnaehana laser maʻamau e hōʻemi i ka walaʻau lawe envelop offset frequency (fCEO) a mālama i nā hiʻohiʻona puʻupuʻu maikaʻi ma ka hope o ke kaulahao amplifier.No ka hoʻokō ʻana i ka hoʻonui ʻana i ka resonance paʻa i loko o ka fsEC, hoʻohana lākou i ʻekolu mau puka mana servo no ka hoʻoponopono ʻana i ka manaʻo, e hopena i ka hoʻoikaika ikaika ʻana i ʻelua degere o ke kūʻokoʻa: ʻo ka manawa huakaʻi o ke kaʻa uila i loko o ka fsEC e pili ana i ka manawa pulse laser, a me ka hoʻololi ʻana o ka pae. o ka mea lawe uwila e pili ana i ka envelope pulupulu ('o ia ho'i, ka mahele enveloppe lawe, ϕCEO).

Ma ka hoʻohana ʻana i ke kinoea krypton e like me ke kinoea hana, ua hoʻokō ka hui noiʻi i ka hana o nā harmonics kiʻekiʻe ma fsEC.Ua hana lākou i nā ana Tr-ARPES o ka graphite a ua nānā i ka thermiation wikiwiki a me ka hoʻohui hou ʻana o nā heluna electron non-thermally hauʻoli, a me ka dynamics o nā mokuʻāina hoʻohiwahiwa ʻole kokoke i ka pae Fermi ma luna o 0.6 eV.Hāʻawi kēia kumu kukui i mea hana koʻikoʻi no ke aʻo ʻana i ke ʻano uila o nā mea paʻakikī.Eia nō naʻe, ʻo ka hana o nā harmonics kiʻekiʻe i ka fsEC he mau koi kiʻekiʻe loa no ka reflectivity, dispersion compensation, hoʻoponopono maikaʻi o ka lōʻihi o ka lua a me ka laka synchronization, e hoʻopilikia nui i ka hoʻonui ʻana o ka lua i hoʻonui ʻia.I ka manawa like, he paʻakikī hoʻi ka pane ʻana o ka pae nonlinear o ka plasma ma ke kiko kiko o ka lua.No laila, i kēia manawa, ʻaʻole i lilo kēia ʻano kumu kukui i ka ultraviolet extreme mainstreamkumu kukui harmonic kiʻekiʻe.