Takaitaccen Bayani:Mun ƙirƙiro jagorar wave na lithium tantalate mai tushen insulator mai nauyin 1550 nm tare da asarar 0.28 dB/cm da kuma ingancin resonator na zobe mai nauyin miliyan 1.1. An yi nazarin aikace-aikacen χ(3) mara layi a cikin photonics marasa layi. Fa'idodin lithium niobate akan insulator (LNoI), wanda ke nuna kyawawan halaye marasa layi na χ(2) da χ(3) tare da ƙaƙƙarfan ɗaurewar gani saboda tsarin "insulator-on", ya haifar da ci gaba mai mahimmanci a cikin fasahar jagorar waveguide don masu daidaita ultrafast da haɗakar photonics marasa layi [1-3]. Baya ga LN, an kuma binciki lithium tantalate (LT) a matsayin kayan photonic marasa layi. Idan aka kwatanta da LN, LT yana da mafi girman matakin lalacewar gani da kuma faɗaɗɗen taga mai bayyana haske [4, 5], kodayake sigogin gani, kamar ma'aunin refractive da ma'aunin marasa layi, suna kama da na LN [6, 7]. Saboda haka, LToI ya yi fice a matsayin wani abu mai ƙarfi da za a iya amfani da shi don aikace-aikacen photonic marasa layi na wutar lantarki mai ƙarfi. Bugu da ƙari, LToI yana zama babban abu don na'urorin tacewa na acoustic wave (SAW), waɗanda ake amfani da su a cikin fasahar wayar hannu mai sauri da mara waya. A cikin wannan mahallin, wafers na LToI na iya zama kayan da aka fi amfani da su don aikace-aikacen photonic. Duk da haka, zuwa yau, an ba da rahoton wasu na'urori kaɗan na photonic bisa ga LToI, kamar su microdisk resonators [8] da electro-optic phase shifters [9]. A cikin wannan takarda, mun gabatar da jagorar LToI mai ƙarancin asara da aikace-aikacensa a cikin resonator zobe. Bugu da ƙari, muna ba da halayen χ(3) marasa layi na jagorar LToI.
Muhimman Abubuwa:
• Yana bayar da wafers LToI mai inci 4 zuwa 6, wafers masu sirara na lithium tantalate, tare da kauri na saman Layer daga 100 nm zuwa 1500 nm, ta amfani da fasahar cikin gida da hanyoyin da suka tsufa.
• SINOI: Wafers ɗin silicon nitride mai ƙarancin asara.
• SICOI: Abubuwan da aka yi da silicon carbide mai kauri mai kauri mai kyau don da'irori masu haɗakar silicon carbide.
• LTOI: Mai ƙarfi ga lithium niobate, wafers ɗin lithium tantalate mai siriri.
• LNOI: LNOI mai inci 8 yana tallafawa samar da kayayyaki masu girman gaske na lithium niobate.
Masana'antu akan Insulator Waveguides:A cikin wannan binciken, mun yi amfani da wafers LToI mai inci 4. Layin LT na sama wani nau'in LT ne mai jujjuyawar Y-cut LT na kasuwanci mai girman 42° don na'urorin SAW, wanda aka haɗa kai tsaye zuwa wani sinadari na Si tare da Layer thermal oxide mai kauri 3 µm, yana amfani da tsarin yankewa mai wayo. Hoto na 1(a) yana nuna saman wafer LToI, tare da kauri saman LT na 200 nm. Mun tantance ƙaiƙayin saman Layer LT na sama ta amfani da na'urar microscopy ta atomic force (AFM).
Siffa ta 1.(a) Kallon saman wafer LToI, (b) Hoton AFM na saman layer ɗin LT na sama, (c) Hoton PFM na saman layer ɗin LT na sama, (d) Sashen giciye na jagorar wave na LToI, (e) An ƙididdige bayanin yanayin TE na asali, da kuma (f) Hoton SEM na tsakiyar jagorar wave na LToI kafin a ajiye saman layer na SiO2. Kamar yadda aka nuna a Hoto na 1 (b), ƙaiƙayin saman bai wuce 1 nm ba, kuma ba a lura da layukan karce ba. Bugu da ƙari, mun bincika yanayin polarization na saman layer ɗin LT ta amfani da na'urar auna ƙarfin amsawar piezoelectric (PFM), kamar yadda aka nuna a Hoto na 1 (c). Mun tabbatar da cewa an kiyaye polarization iri ɗaya ko da bayan tsarin haɗin gwiwa.
Ta amfani da wannan substrate na LToI, mun ƙera jagorar waveguide kamar haka. Da farko, an ajiye wani Layer na abin rufe fuska na ƙarfe don yin LT ɗin bushewa daga baya. Sannan, an yi lithography na electron beam (EB) don ayyana tsarin tsakiya na waveguide a saman Layer na abin rufe fuska na ƙarfe. Na gaba, mun canja tsarin juriya na EB zuwa Layer na abin rufe fuska na ƙarfe ta hanyar etching bushe. Bayan haka, an samar da core na LToI waveguide ta amfani da etching na plasma na electron cyclotron resonance (ECR). A ƙarshe, an cire Layer na abin rufe fuska na ƙarfe ta hanyar tsari mai danshi, kuma an sanya wani Layer na SiO2 mai rufewa ta amfani da ajiyar tururin sinadarai da aka inganta a cikin plasma. Hoto na 1 (d) yana nuna ɓangaren giciye na jagorar waveguide na LToI. Jimlar tsayin tsakiya, tsayin farantin, da faɗin tsakiya sune 200 nm, 100 nm, da 1000 nm, bi da bi. Lura cewa faɗin tsakiya yana faɗaɗa zuwa 3 µm a gefen jagorar waveguide don haɗa fiber na gani.
Siffa ta 1 (e) tana nuna rarrabawar ƙarfin gani da aka ƙididdige na yanayin lantarki mai wucewa ta asali (TE) a 1550 nm. Siffa ta 1 (f) tana nuna hoton na'urar hangen nesa ta lantarki (SEM) na tsakiyar jagorar LToI kafin a ajiye saman layin SiO2.
Halayen Jagoran Raƙuman Ruwa:Da farko mun kimanta halayen asarar layi ta hanyar shigar da hasken TE-polarized daga tushen fitar da iska mai ƙarfin 1550 nm mai ƙarfin radadi zuwa cikin jagororin raƙuman LToI masu tsayi daban-daban. An samo asarar yaɗuwa daga gangaren dangantakar da ke tsakanin tsawon jagorar raƙuman ruwa da watsawa a kowane tsawon raƙuman ruwa. Asarar yaɗuwar da aka auna sune 0.32, 0.28, da 0.26 dB/cm a 1530, 1550, da 1570 nm, bi da bi, kamar yadda aka nuna a Hoto na 2 (a). Jagororin raƙuman LToI da aka ƙera sun nuna ƙarancin asara daidai da jagororin raƙuman LNoI na zamani [10].
Na gaba, mun tantance rashin daidaituwar χ(3) ta hanyar canjin tsawon raƙuman ruwa da aka samar ta hanyar haɗa raƙuman ruwa huɗu. Mun shigar da hasken famfon raƙuman ruwa mai ci gaba a 1550.0 nm da kuma hasken sigina a 1550.6 nm cikin jagorar raƙuman ruwa mai tsawon mm 12. Kamar yadda aka nuna a Hoto na 2 (b), ƙarfin siginar raƙuman haske mai haɗuwa da lokaci (idler) ya ƙaru tare da ƙaruwar ƙarfin shigarwa. Shigarwa a Hoto na 2 (b) yana nuna yanayin fitarwa na cakuda raƙuman ruwa huɗu. Daga alaƙar da ke tsakanin ƙarfin shigarwa da ingancin juyawa, mun kiyasta sigar mara layi (γ) ta kasance kusan 11 W^-1m.
Hoto na 3.(a) Hoton na'urar hangen nesa ta zobe da aka ƙera. (b) Siginar watsawa ta zobe mai sigogi daban-daban na gibi. (c) Siginar watsawa da aka auna da kuma wanda aka sanya wa Lorentzian na'urar hangen nesa ta zobe mai gibi na 1000 nm.
Na gaba, mun ƙera resonator na zobe na LToI kuma muka kimanta halayensa. Hoto na 3 (a) yana nuna hoton na'urar hangen nesa ta resonator na zobe da aka ƙera. Resonator na zobe yana da tsarin "wasan tsere", wanda ya ƙunshi yanki mai lanƙwasa tare da radius na 100 µm da kuma yanki madaidaiciya na 100 µm a tsawonsa. Faɗin rata tsakanin zobe da tsakiyar jagorar raƙuman bas ya bambanta a cikin ƙaruwa na 200 nm, musamman a 800, 1000, da 1200 nm. Hoto na 3 (b) yana nuna siginar watsawa don kowane rata, yana nuna cewa rabon ɓacewa yana canzawa tare da girman rata. Daga waɗannan siginar, mun ƙaddara cewa rata na 1000 nm yana ba da kusan yanayin haɗin kai mai mahimmanci, saboda yana nuna mafi girman rabon ɓacewa na -26 dB.
Ta amfani da resonator mai haɗakarwa, mun kimanta ingancin factor (Q factor) ta hanyar haɗa layin watsawa tare da lanƙwasa na Lorentzian, inda muka sami factor na ciki na Q na miliyan 1.1, kamar yadda aka nuna a Hoto na 3 (c). A saninmu, wannan shine gwaji na farko na resonator zobe na LToI mai haɗin waveguide. Abin lura shi ne, ƙimar Q factor da muka samu ya fi na resonators na microdisk na LToI mai haɗin fiber [9].
Kammalawa:Mun ƙirƙiro jagorar wave na LToI tare da asarar 0.28 dB/cm a 1550 nm da kuma ma'aunin Q na zobe mai ƙarfin Q na miliyan 1.1. Aikin da aka samu ya yi daidai da na jagorar wave na LNoI mai ƙarancin asara ta zamani. Bugu da ƙari, mun bincika rashin daidaituwar χ(3) na jagorar wave na LToI da aka ƙera don aikace-aikacen da ba na layi ba.
Lokacin Saƙo: Nuwamba-20-2024