Laser yophatikizika komanso yolimba yapakati pa infrared (MIR) pa 6.45 um yokhala ndi mphamvu zambiri zotulutsa komanso mtundu wamtengo wapafupi wa Gaussian umawonetsedwa kHz imapezedwa pogwiritsa ntchito ZnGeP2 (ZGP) Optical parametric oscillator (OPO) 。Iyi ndi mphamvu yapamwamba kwambiri pa 6.45 um ya laser iliyonse yolimba kwambiri momwe tingadziwire.Mtengo wapakati wa mtengo wamtengo umayesedwa kukhala M2=1.19.
Kuphatikiza apo, kukhazikika kwamphamvu kwamphamvu kumatsimikiziridwa, ndi kusinthasintha kwamphamvu kosakwana 1.35% rms kupitilira 2 h, ndipo laser imatha kuthamanga bwino kwa maola opitilira 500. Kuphatikiza apo, kuwonongeka kwa chikole kumawunikidwa kwa nthawi yoyamba, monga momwe tikudziwira, ndipo zotsatira zake zikuwonetsa kuti laser ya MIR ili ndi kuthekera kwabwino kwambiri kochotsa ma elekitironi, kupangitsa kuti ikhale m'malo mwa ma elekitironi aulere.©2022 Optica Publishing Group

https://doi.org/10.1364/OL.446336

Mid-infrared (MIR) 6.45 um laser radiation imatha kugwiritsidwa ntchito m'madipatimenti amankhwala olondola kwambiri chifukwa chaubwino wake wokhala ndi kutsika kocheperako komanso kuwonongeka pang'ono [1】.Malaza a ma elekitironi aulere (FELs), ma laser strontium vapor, gasi Ma lasers a Raman, ndi ma laser olimba a boma ozikidwa pa oscillator optical paramet-ric oscillator (OPO) kapena kusiyana kwa frequency generation (DFG) amagwiritsidwa ntchito kwambiri 6.45 um laser sources. application.
Kafukufuku adawonetsa kuti ma lasers a 6.45 um solid-state amatulutsa mitundu yaying'ono yotentha yotentha m'matenda achilengedwe komanso kuti kuya kwake kumakhala kozama kuposa kwa FEL pansi pamikhalidwe yomweyi, zomwe zimatsimikizira kuti zimatha. kugwiritsidwa ntchito ngati njira ina yabwino kwa ma FEL pochotsa minofu yachilengedwe [2】.Kuphatikiza apo, ma lasers olimba-boma ali ndi ubwino wokhala ndi mawonekedwe ophatikizika, kukhazikika kwabwino, komanso

kugwiritsira ntchito piritsi, kuwapangitsa kukhala zida zodalirika zopezera gwero la kuwala kwa a6.45μn.Monga zidziwikiratu, makristalo osakhala amtundu wa infrared amatenga gawo lofunikira pakusinthira pafupipafupi komwe amagwiritsidwa ntchito kuti akwaniritse ma laser a MIR apamwamba kwambiri. Zoyenera kupanga ma lasers a MIR.Makhiristo awa amaphatikiza ma chalcogenides ambiri, monga AgGaS2 (AGS) 【3,41, LiInS2 (LIS) 【5,61, LilnSe2 (LISe) 【7】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】, ndi BaGaSe (BGSe) 【10-12】, komanso mankhwala a phosphorous CdSiP2 (CSP) 【13-16】 ndi ZnGeP2 (ZGP) 【17】; awiri otsirizawa onse ali ndi maubwenzi akuluakulu osagwirizanitsa. Mwachitsanzo, ma radiation a MIR amatha kupezeka pogwiritsa ntchito CSP-OPOs.Komabe, ma CSP-OPO ambiri amagwira ntchito pamlingo wanthawi yayitali (pico-ndi femtosecond) ndipo amapoperedwa ndi pafupifupi 1 um mode-zokhoma lasers. SPOPO) machitidwe ali ndi dongosolo lovuta ndipo ndi okwera mtengo.Mphamvu zawo zambiri ndizotsika kuposa 100 mW pafupi ndi 6.45 um【13-16】.Poyerekeza ndi CSP crystal, ZGP ili ndi laser yowonongeka kwambiri.kusunga (60 MW/cm2), apamwamba matenthedwe conductiv-ity (0.36 W/cm K), ndi wofananira nonlinear coefficient (75pm/V) . kugwiritsa ntchito mphamvu 【18-221.Mwachitsanzo, chibowo chathyathyathya-lathyathyathya ZGP-OPO chokhala ndi machunidwe osiyanasiyana a 3.8-12.4 um chopopedwa ndi 2.93 um laser chinawonetsedwa.Kuphatikizika kwamphamvu kwapang'onopang'ono kwa kuwala kosagwira ntchito pa 6.6 um kunali 1.2 mJ 【201.Kwa kutalika kwake kwa 6.45 um, mphamvu ya maxi-mum single-pulse ya 5.67 mJ pa kubwerezabwereza kwa 100 Hz inapezedwa pogwiritsa ntchito mphete ya OPO yopanda ndondomeko yochokera ku crystal ya ZGP.Ndi kubwerezabwereza kwa 100 Hz. mafupipafupi a 200Hz, mphamvu yotulutsa mphamvu ya 0.95 W inafikiridwa 【221.Monga momwe tikudziwira, iyi ndi mphamvu yapamwamba kwambiri yomwe imapezeka pa 6.45 um.Kafukufuku amene alipo akusonyeza kuti mphamvu yapamwamba ndiyofunika kuti minofu ikhale yogwira mtima [23】.Choncho, kupangidwa kwa gwero la laser lamphamvu kwambiri la 6.45 um kungakhale kofunikira kwambiri popititsa patsogolo mankhwala achilengedwe.Mu Kalata iyi, timapereka lipoti losavuta, lokhazikika-lokhazikika la MIR 6.45 um laser lomwe lili ndi mphamvu zambiri zotulutsa ndipo limachokera pa ZGP-OPO yomwe imapopedwa ndi nanosecond (ns)-pulse 2.09 um

Mphamvu yapakati yotulutsa ya 6.45 um laser imafika ku 1.53 W yokhala ndi kugunda m'lifupi pafupifupi 42ns pa kubwerezabwereza kwa 10 kHz, ndipo ili ndi mtengo wabwino kwambiri wamtengo. Ntchitoyi ikuwonetsa kuti laser ndi njira yabwino yochotsera minofu yeniyeni, chifukwa imakhala ngati laser scalpel.Kukonzekera koyesera kumajambulidwa mu Fig.1.ZGP-OPO imapopedwa ndi LD-pumped 2.09 um Ho:YAG laser yomwe imapereka 28 W ya mphamvu yapakati pa 10 kHz. FWHM) komanso pafupifupi mtengo wamtengo wapatali wa M2 wa pafupifupi 1.7.MI ndi M2 ndi magalasi awiri a 45 okhala ndi zokutira zomwe zimawunikira kwambiri pa 2.09 um. F2 = 100 mm) amagwiritsidwa ntchito polumikizira mtengo ndi m'mimba mwake pafupifupi 3.5 mm mu crystal ya ZGP. An Optical isolator (ISO) imagwiritsidwa ntchito poletsa mtengo wa mpope kubwerera ku gwero la mpope la 2.09 um. (HWP) pa 2.09 um imagwiritsidwa ntchito poyang'anira polarization ya nyali ya mpope.M3 ndi M4 ndi magalasi a OPO patsekeke, okhala ndi CaF2 yathyathyathya yomwe imagwiritsidwa ntchito ngati gawo lapansi.Galasi lakutsogolo M3 ndi anti-reflection TACHIMATA (98%) mtengo ndi zowoneka bwino kwambiri (98%) za 6.45 um idler ndi 3.09 um sign ma wave.um ndi 3.09 um ndipo amalola kufalitsa pang'ono kwa 6.45 um idler.Krustalo ya ZGP imadulidwa pa6-77.6 ° andp = 45 ° pamtundu-JⅡ gawo lofananira 【2090.0 (o) 6450.0 (o)+3091.9 (e)】, yomwe ili yoyenera kwambiri pamtundu wina wapang'onopang'ono wokhala ndi mafunde ang'onoang'ono ang'onoang'ono okhala ndi mafunde ang'onoang'ono ang'onoang'ono. Kukula kwa kristalo wa ZGP ndi 5mm x 6 mm x 25 mm, ndipo ndi yopukutidwa ndi anti-reflection yokutidwa kumbali zonse ziwiri za mafunde atatu omwe ali pamwambawa. yokhazikika mumadzi otentha amkuwa ndi kuziziritsa kwa madzi (T = 16) . Kutalika kwa patsekeke ndi 27 mm. Nthawi yozungulira ya OPO ndi 0.537 ns ya laser mpope. -on-I njira 【17】.Kuwonongeka kwa kristalo wa ZGP kunayesedwa kuti ndi 0.11 J/cm2 pa 10 kHz.mukuyesaku, molingana ndi kuchuluka kwamphamvu kwamphamvu kwa 1.4 MW/cm2, komwe kumakhala kochepa chifukwa cha ndi osauka ❖ kuyanika khalidwe.Mphamvu yotulutsa ya kuwala kopangidwa mopanda ntchito imayesedwa ndi mita ya mphamvu (D, OPHIR, 1 uW mpaka 3 W), ndipo kutalika kwa mawonekedwe a kuwala kumawunikidwa ndi spectrometer (APE, 1.5-6.3 m). kupeza mphamvu linanena bungwe lalikulu 6.45 um, ife optim-mize mapangidwe magawo a OPO.A manambala kayeseleledwe ikuchitika kutengera atatu yoweyula kusakaniza chiphunzitso ndi paraxial kufalitsa cquations 【24,25】; mu kayeseleledwe, ife gwiritsani ntchito magawo omwe akugwirizana ndi zoyeserera ndikuyerekeza kugunda kwamphamvu ndi mbiri ya Gaussian mumlengalenga ndi nthawi.

transmittance, mphamvu yapampope, komanso mphamvu zotulutsa zimakongoletsedwa ndi kuwongolera kachulukidwe kampopi m'bowo kuti akwaniritse mphamvu yotulutsa mphamvu panthawi imodzi ndikupewa kuwonongeka kwa kristalo wa ZGP ndi zinthu zowoneka. W ya ntchito ya ZGP-OPO.Zotsatira zofananira zikuwonetsa kuti pomwe cholumikizira chomwe chili ndi ma transmittance a 50% chimagwiritsidwa ntchito, kuchuluka kwamphamvu kwamphamvu kwambiri kumangokhala 2.6 x 10 W/cm2 mu ZGP kulira-tal, komanso mphamvu zotulutsa. Zoposa 1.5 W zitha kupezeka. Chithunzi 2 chikuwonetsa mgwirizano pakati pa mphamvu yotulutsa yoyezera ya osagwira ntchito pa 6.45 um ndi mphamvu ya mpope yochitika. Zitha kuwoneka kuchokera ku Chithunzi 2 kuti mphamvu yotulutsa ya wosasamala imawonjezeka monyanyira ndi Mphamvu ya mpope ya zochitika. Kufikira kwa mpope kumafanana ndi mphamvu ya mpope ya 3.55WA pazipita kutulutsa mphamvu zopanda ntchito za 1.53 W imapezeka pa mphamvu ya mpope ya pafupifupi 18.7 W, yomwe imagwirizana ndi kutembenuka kwa kuwala kwa kuwalaf pafupifupi 8.20%% ndi quantum conversion cfliciency of 25.31%.Pa chitetezo cha nthawi yayitali, laser imayendetsedwa pafupi ndi 70% ya mphamvu zake zazikulu zotuluka. zomwe zikuwonetsedwa muzolemba (a) mu Fig.2. Zimapezeka kuti kusinthasintha kwa mphamvu yoyezera kumakhala kochepa kuposa 1.35% rms mu 2 h, komanso kuti laser imatha kugwira ntchito bwino kwa maola oposa 500. Amayezedwa m'malo mwa waulength chifukwa cha kutalika kwa kutalika kwa spectrometer (APE, 1.5-6.3 um) yomwe imagwiritsidwa ntchito poyesera.Kutalikirana kwa chizindikiro kumakhala pakati pa 3.09 um ndipo m'lifupi mwake ndi pafupifupi 0.3 nm, monga momwe tawonetsera. mkati (b) wa Fig.2.Kutalikirana kwapakati kwa munthu wosagwira ntchito kumaganiziridwa kuti ndi 6.45um.Kuthamanga kwa mpweya wa munthu wosagwira ntchito kumazindikiridwa ndi photodetector (Thorlabs,PDAVJ10) ndipo amalembedwa ndi oscilloscope ya digito (Tcktronix), (Mawonekedwe a mawonekedwe a oscilloscope akuwonetsedwa mu Fig.3 ndikuwonetsa kugunda kwapakati pafupifupi 42 ns.ndi 41.18% yocheperapo kwa 6.45 um idler poyerekeza ndi 2.09 um pump pulse chifukwa cha kupindula kwakanthawi kochepa kwa njira yosinthira pafupipafupi. 6.45 um idler amayezedwa ndi mtengo wa laser

analyzer (Spiricon, M2-200-PIII) pa 1 W ya mphamvu yotulutsa, monga momwe tawonetsera mu Fig.4. Miyezo yoyezedwa ya M2 ndi M, 2 ndi 1.32 ndi 1.06 pamodzi ndi x axis ndi y axis, motsatira, motsatira chiwerengero cha mtengo wamtengo wapatali wa M2 = 1.19. The insct of Fig.4 imasonyeza mawonekedwe awiri (2D) amtengo wapatali, omwe ali ndi pafupi ndi Gaussian spatial mode. kuyesa kwa umboni wa mfundo zokhuza laser ablation ya porcine brain ikuchitika. Lens ya f = 50 imagwiritsidwa ntchito kuyang'ana 6.45 um pulse beam mpaka m'chiuno chozungulira pafupifupi 0.75 mm. imayikidwa pa cholinga cha laser beam. Kutentha kwa pamwamba (T) kwa minofu yachilengedwe monga ntchito ya malo ozungulira r imayesedwa ndi thermocamera (FLIR A615) synchronously panthawi ya ablation. , 2, 4, 6, 10, ndi 20 s pa mphamvu ya laser ya I W. Pa nthawi iliyonse yamagetsi, malo asanu ndi limodzi amapangidwa: r = 0,0.62,0.703,1.91,3.05, ndi 4.14 mm m'mbali mwa njira yozungulira potengera malo apakati a malo owala, monga momwe tawonetsera mkuyu. pa malo ablation pa minofu kumawonjezeka ndi kuwonjezeka walitsa nthawi.The apamwamba kutentha-T pa malo mfundo r = 0 ndi 132.39,160.32,196.34;

205.57,206.95, ndi 226.05C kwa nthawi walitsa wa 1,2,4,6,10, ndi 20 s, motero. Thermal conduction theory for biological tissue126】ndi chiphunzitso cha laser propagation mu biological tissue 【27】yophatikizidwa ndi magawo a kuwala a porcine brain 1281.
Kuyerekeza kumachitika potengera mtengo wa Gaussian. mawonekedwe a cylinder for simula-tion.Zigawo zomwe zimagwiritsidwa ntchito poyerekezera zikufotokozedwa mwachidule mu Table 1. Mipiringidzo yolimba yomwe ikuwonetsedwa mu Fig.5 ndi yofanana ndi yogawa kutentha kwa radial molingana ndi malo ablation pamtunda wa minofu kwa kuwala kosiyana siyana. durations.Amawonetsa mbiri ya kutentha kwa Gaussian kuchokera pakati kupita ku periphery.Zikuwonekera kuchokera ku Fig.5 kuti deta yoyesera imagwirizanitsa bwino ndi zotsatira zofananitsa.Zikuwonekeranso kuchokera ku Fig.5 kuti kutentha kofanana pakati pa malo apakati. Kafukufuku wam'mbuyomu wasonyeza kuti ma cell omwe ali mu minofu amakhala otetezeka pakanthawi kochepa.55C, zomwe zikutanthauza kuti maselo amakhalabe achangu m'madera obiriwira (T <55C) a ma curve mu Fig.5. The yellow zone of each curve (55C)60C) .Izo zikhoza kuwonedwa mu Fig.5 kuti yoyerekeza ablation radii pa T = 60 ° Care0.774,0.873,0.993,1.071,1.198 ndi 1.364 mm, motero, kwa nthawi walitsa wa 1,2,4,6, 10, ndi 20s, pamene zoyerekeza ablation radii paT = 55C ndi0.805,0.908,1.037,1.134,1.271, ndi 1.456 mm, motero. 2.394,3.098,3.604,4.509,ndi5.845 mm2 kwa 1,2,4,6,10,ndi 20s wa walitsa, motero.Dera ndi chikole kuwonongeka m'dera akupezeka 0.003,0.0040.006,0.013,0.013, ndi 0.027 mm2. Zitha kuwoneka kuti madera a laser ablation ndi madera owonongeka akuwonjezeka ndi nthawi ya kuyatsa.Timatanthauzira chiwongoladzanja cha kuwonongeka kwa chiwongoladzanja kukhala chiŵerengero cha malo owonongeka kwa 55C s T60C. Chiŵerengero cha kuwonongeka kwa chikole chimapezeka. kukhala 8.17%, 8.18%, 9.06%, 12.11%, 12.56%, ndi 13.94% kwa nthawi zosiyanasiyana walitsa, kutanthauza kuti chikole kuwonongeka kwa zimakhala ablated ndi yaying'ono.Chotero, mabuku experimental deta ndi zotsatira zofananira zikuwonetsa kuti laser yaying'ono, yamphamvu, yolimba-yonse 6.45 um ZGP-OPO imapereka kuchotseratu minofu yachilengedwe. MIR pulsed 6.45 um laser source kutengera njira ya ns ZGP-OPO. Mphamvu yayikulu kwambiri ya 1.53 W idapezedwa ndi mphamvu yayikulu ya 3.65kW komanso mtundu wapakati wa mtengo wa M2=1.19. Pogwiritsa ntchito ma radiation a 6.45 um MIR, a kuyesera umboni wa mfundo pa laser ablation ya minofu inachitidwa.Kugawidwa kwa kutentha pa minofu yowonongeka kunayesedwa moyesera komanso mongoyerekeza. Deta yoyezedwa inagwirizana bwino ndi zotsatira zofananira. Komanso, kuwonongeka kwa chikole kunayesedwa mwachidziwitso. Zotsatira izi zimatsimikizira kuti piritsi lathu la MIR pulse laser pa 6.45 um limapereka kuchotseratu ma biological tissucs ndipo lili ndi kuthekera kwakukulu kokhala chida chothandiza mu sayansi ya zamankhwala ndi zachilengedwe, chifukwa chitha kulowa m'malo mwa FEL yayikulu kwambiri.laser scalpel.