Laser thiab nws cov txheej txheem

1. Lub hauv paus ntsiab lus ntawm laser tiam

Cov qauv atomic zoo li lub hnub ci me me, nrog cov atomic nucleus nyob nruab nrab. Cov electrons tas li tig ib ncig ntawm lub atomic nucleus, thiab lub atomic nucleus tseem tig mus tas li.

Lub nucleus yog tsim los ntawm protons thiab neutrons. Protons raug them zoo thiab neutrons tsis raug them. Tus naj npawb ntawm cov nqi zoo nqa los ntawm tag nrho cov nucleus yog sib npaug rau cov nqi tsis zoo uas nqa los ntawm tag nrho cov electrons, yog li feem ntau atoms yog nruab nrab rau lub ntiaj teb sab nraud.

Raws li qhov loj ntawm ib lub atom muaj kev txhawj xeeb, lub nucleus concentrates feem ntau ntawm lub atom, thiab cov huab hwm coj nyob ntawm tag nrho cov electrons yog heev me me. Nyob rau hauv cov qauv atomic, lub nucleus tsuas yog nyob ib qho chaw me me xwb. Cov electrons tig ib ncig ntawm lub nucleus, thiab cov electrons muaj qhov chaw loj dua rau kev ua si.

Atoms muaj "sab hauv zog", uas muaj ob feem: ib qho yog tias cov electrons muaj lub orbiting ceev thiab ib tug tej yam kinetic zog; Lwm qhov yog tias muaj qhov nrug deb ntawm qhov tsis zoo ntawm cov hluav taws xob hluav taws xob thiab cov khoom siv hluav taws xob zoo, thiab muaj qee qhov peev xwm ntawm lub zog. Cov txiaj ntsig ntawm lub zog kinetic thiab lub zog muaj peev xwm ntawm tag nrho cov electrons yog lub zog ntawm tag nrho cov atom, uas yog hu ua lub zog sab hauv ntawm lub atom.

Tag nrho cov electrons tig ib ncig ntawm lub nucleus; qee zaum ze rau lub nucleus, lub zog ntawm cov electrons no me dua; qee zaum deb ntawm lub nucleus, lub zog ntawm cov electrons loj dua; Raws li qhov tshwm sim tshwm sim, tib neeg faib cov txheej txheem hluav taws xob rau hauv qhov sib txawv ""Qib Zog"; Ntawm ib qho "Qib Zog", tej zaum yuav muaj ntau lub tshuab hluav taws xob orbiting nquag, thiab txhua lub tshuab hluav taws xob tsis muaj lub voj voog ruaj khov, tab sis cov hluav taws xob no txhua tus muaj tib theem ntawm lub zog; "Energy Levels" yog cais los ntawm ib leeg. Yog lawm, lawv raug cais raws li qib zog. Lub tswv yim ntawm "theem zog" tsis tsuas yog faib cov electrons rau hauv qib raws li lub zog, tab sis kuj faib qhov chaw orbiting ntawm electrons mus rau ntau theem. Nyob rau hauv luv luv, ib tug atom tej zaum yuav muaj ntau lub zog, thiab txawv zog theem sib txawv zog; Qee cov electrons orbit nyob rau ntawm "tsawg zog" thiab qee cov electrons orbit ntawm "siab zog".

Niaj hnub no, cov phau ntawv physics hauv tsev kawm ntawv theem nrab tau qhia meej meej txog cov yam ntxwv ntawm qee cov atoms, cov kev cai ntawm kev faib hluav taws xob hauv txhua txheej electron, thiab cov xov tooj ntawm cov hluav taws xob ntawm cov qib sib txawv.

Nyob rau hauv ib qho atomic system, electrons yeej txav mus rau hauv cov khaubncaws sab nraud povtseg, nrog qee cov atoms ntawm lub zog siab thiab qee qhov qis zog; vim hais tias atoms yeej ib txwm cuam tshuam los ntawm ib puag ncig sab nraud (kub, hluav taws xob, hlau nplaum), qib siab hluav taws xob hluav taws xob tsis ruaj khov thiab yuav hloov pauv hloov mus rau qib qis zog, nws cov nyhuv yuav nqus tau, lossis nws yuav ua rau muaj kev cuam tshuam tshwj xeeb thiab ua rau " spontaneous emission." Yog li ntawd, nyob rau hauv lub atomic system, thaum high-zog electrons hloov mus rau qis-zog theem, yuav muaj ob manifestations: "spontaneous emission" thiab "stimulated emission".

Raws li cov hluav taws xob hluav taws xob, cov hluav taws xob hauv lub xeev muaj zog tsis ruaj khov thiab, cuam tshuam los ntawm ib puag ncig sab nraud (kub, hluav taws xob, hluav taws xob, hlau nplaum), spontaneously tsiv mus rau lub xeev qis zog, thiab lub zog ntau dhau yog radiated nyob rau hauv daim ntawv ntawm photons. Cov yam ntxwv ntawm cov hluav taws xob zoo li no yog qhov kev hloov ntawm txhua lub electron yog ua los ntawm nws tus kheej thiab yog random. Lub xeev photon ntawm spontaneous emission ntawm txawv electrons txawv. Lub spontaneous emissions ntawm lub teeb yog nyob rau hauv ib tug "incoherent" lub xeev thiab muaj tawg khiav ri niab cov lus qhia. Txawm li cas los xij, spontaneous hluav taws xob muaj cov yam ntxwv ntawm cov atoms lawv tus kheej, thiab cov spectra ntawm spontaneous hluav taws xob ntawm txawv atoms txawv. Hais txog qhov no, nws ua rau neeg nco txog qhov kev paub hauv physics, "Txhua yam khoom muaj peev xwm ua kom muaj cua sov, thiab cov khoom muaj peev xwm ua kom tsis tu ncua nqus thiab tawm suab hluav taws xob. Cov hluav taws xob hluav taws xob hluav taws xob hluav taws xob los ntawm tshav kub muaj qee qhov kev faib tawm spectrum. Qhov no spectrum Qhov kev faib khoom muaj feem xyuam rau cov khoom ntawm cov khoom nws tus kheej thiab nws qhov kub thiab txias. " Yog li ntawd, yog vim li cas rau lub hav zoov ntawm thermal tawg yog lub spontaneous emission ntawm atoms.

Nyob rau hauv stimuled emission, high-zog electrons hloov mus rau ib tug tsawg-zog theem nyob rau hauv lub "stimulation" los yog "induction" ntawm "photons haum rau tej yam kev mob" thiab radiate ib tug photon ntawm tib zaus raws li qhov teeb meem photon. Qhov loj tshaj plaws ntawm cov hluav taws xob tsim hluav taws xob yog tias cov photons tsim los ntawm cov hluav taws xob tsim hluav taws xob muaj tib lub xeev raws li qhov xwm txheej photons uas tsim hluav taws xob txhawb zog. Lawv nyob hauv lub xeev "coherent". Lawv muaj tib zaus thiab tib qhov kev taw qhia, thiab nws tsis yooj yim sua kom paub qhov txawv ntawm ob. qhov sib txawv ntawm cov. Nyob rau hauv txoj kev no, ib tug photon ua ob zoo tib yam photons los ntawm ib tug stimulated emission. Qhov no txhais tau hais tias lub teeb yog intensified, los yog "amplified".

Tam sim no cia peb txheeb xyuas dua, cov xwm txheej twg yuav tsum tau ua kom tau txais hluav taws xob ntau thiab ntau zaus?

Raws li ib txwm muaj, tus naj npawb ntawm electrons nyob rau hauv siab zog yog ib txwm tsawg dua li cov electrons nyob rau hauv qis zog. Yog tias koj xav tau atoms los tsim cov hluav taws xob tsim hluav taws xob, koj xav kom cov hluav taws xob ntau ntxiv hauv cov hluav taws xob siab, yog li koj xav tau "tswj qhov chaw", uas nws lub hom phiaj yog los txhawb kom muaj zog ntau dhau ntawm cov hluav taws xob qis hluav taws xob dhia mus rau qib siab zog. , yog li tus naj npawb ntawm cov hluav taws xob hluav taws xob siab yuav ntau dua li cov hluav taws xob qis hluav taws xob, thiab "particle tooj thim rov qab" yuav tshwm sim. Ntau lub zog hluav taws xob ntau dhau ntawm cov hluav taws xob hluav taws xob tuaj yeem nyob rau lub sijhawm luv luv. Lub sij hawm yuav dhia mus rau theem qis zog, yog li qhov ua tau ntawm kev txhawb nqa emission ntawm hluav taws xob yuav nce.

Tau kawg, "tswj qhov chaw" yog teem rau txawv atoms. Nws ua rau cov hluav taws xob "resonate" thiab tso cai rau qib qis zog hluav taws xob ntau dua kom dhia mus rau qib siab zog. Cov neeg nyeem tuaj yeem nkag siab yooj yim, laser yog dab tsi? Laser ua li cas? Laser yog "lub teeb hluav taws xob" uas yog "zoo siab" los ntawm atoms ntawm ib yam khoom nyob rau hauv qhov kev txiav txim ntawm ib qho "tswj qhov chaw". Qhov no yog laser.