Cov khoom siv lithium tantalate (LTOI) nyias-zaj duab xis tab tom tshwm sim ua lub zog tshiab tseem ceeb hauv kev sib xyaw ua ke optics. Xyoo no, ntau cov haujlwm siab ntawm LTOI modulators tau luam tawm, nrog rau cov wafers LTOI zoo uas muab los ntawm Xibfwb Xin Ou los ntawm Shanghai Institute of Microsystem thiab Information Technology, thiab cov txheej txheem waveguide etching zoo tsim los ntawm Xibfwb Kippenberg pawg ntawm EPFL, Switzerland. Lawv cov kev sib koom tes tau ua rau pom cov txiaj ntsig zoo kawg. Tsis tas li ntawd, cov pab pawg tshawb fawb los ntawm Zhejiang University coj los ntawm Xibfwb Liu Liu thiab Harvard University coj los ntawm Xibfwb Loncar kuj tau tshaj tawm txog cov modulators LTOI ceev ceev, ruaj khov siab.
Ua ib tug txheeb ze ze ntawm lithium niobate nyias-zaj duab xis (LNOI), LTOI khaws cia qhov kev hloov pauv ceev ceev thiab cov yam ntxwv qis-poob ntawm lithium niobate thaum tseem muab cov txiaj ntsig xws li tus nqi qis, birefringence qis, thiab txo cov teebmeem photorefractive. Kev sib piv ntawm cov yam ntxwv tseem ceeb ntawm ob yam khoom tau nthuav tawm hauv qab no.
◆ Kev zoo sib xws ntawm Lithium Tantalate (LTOI) thiab Lithium Niobate (LNOI)
①Cov ntsuas kev cuam tshuam:2.12 piv rau 2.21
Qhov no txhais tau hais tias qhov ntev ntawm ib hom waveguide, qhov khoov vojvoog, thiab qhov loj ntawm cov khoom siv passive raws li ob qho khoom siv zoo sib xws, thiab lawv cov kev ua haujlwm fiber coupling kuj sib piv tau. Nrog rau kev ua kom zoo ntawm waveguide, ob qho khoom siv tuaj yeem ua tiav qhov poob ntawm<0.1 dB/cm. EPFL tshaj tawm tias waveguide poob ntawm 5.6 dB/m.
②Coefficient ntawm Electro-optic:30.5 teev tsaus ntuj/V piv rau 30.9 teev tsaus ntuj/V
Qhov kev ua haujlwm ntawm kev hloov kho yog sib piv rau ob qho khoom siv, nrog rau kev hloov kho raws li Pockels effect, tso cai rau bandwidth siab. Tam sim no, LTOI modulators muaj peev xwm ua tiav 400G ib txoj kab kev ua tau zoo, nrog rau bandwidth tshaj 110 GHz.
③Qhov sib txawv ntawm Bandgap:3.93 eV piv rau 3.78 eV
Ob qho tib si cov ntaub ntawv muaj lub qhov rais dav dav, txhawb nqa cov ntawv thov los ntawm qhov pom mus rau infrared wavelengths, tsis muaj kev nqus hauv cov kab sib txuas lus.
④Tus lej thib ob ntawm Nonlinear Coefficient (d33):21 teev tsaus ntuj/V piv rau 27 teev tsaus ntuj/V
Yog tias siv rau cov ntawv thov nonlinear xws li tiam harmonic thib ob (SHG), tiam sib txawv zaus (DFG), lossis tiam sib sau ua ke zaus (SFG), qhov kev hloov pauv ntawm ob yam khoom yuav tsum zoo sib xws.
◆ Qhov Zoo ntawm Tus Nqi ntawm LTOI piv rau LNOI
①Tus nqi qis dua ntawm kev npaj wafer
LNOI xav tau He ion implantation rau kev sib cais txheej, uas muaj qhov ua haujlwm ionization qis. Qhov sib piv, LTOI siv H ion implantation rau kev sib cais, zoo ib yam li SOI, nrog rau kev ua haujlwm delamination ntau dua 10 npaug ntau dua LNOI. Qhov no ua rau muaj qhov sib txawv ntawm tus nqi rau 6-nti wafers: $ 300 vs. $ 2000, txo tus nqi 85%.
②Nws twb tau siv dav hauv kev lag luam khoom siv hluav taws xob rau cov ntxaij lim dej acoustic(750,000 units txhua xyoo, siv los ntawm Samsung, Apple, Sony, thiab lwm yam).
◆ Cov txiaj ntsig ntawm kev ua tau zoo ntawm LTOI vs LNOI
①Tsawg dua qhov tsis zoo ntawm cov khoom siv, qhov cuam tshuam photorefractive tsis muaj zog, kev ruaj khov ntau dua
Thaum xub thawj, LNOI modulators feem ntau pom tias muaj qhov tsis sib xws, feem ntau yog vim muaj kev sib sau ua ke ntawm cov nqi los ntawm qhov tsis zoo ntawm qhov interface waveguide. Yog tias tsis kho, cov khoom siv no yuav siv sijhawm txog ib hnub kom ruaj khov. Txawm li cas los xij, ntau txoj hauv kev tau tsim los daws qhov teeb meem no, xws li siv cov hlau oxide cladding, substrate polarization, thiab annealing, ua rau qhov teeb meem no feem ntau tswj tau tam sim no.
Qhov sib txawv, LTOI muaj tsawg dua qhov tsis zoo ntawm cov khoom siv, ua rau muaj kev cuam tshuam tsawg dua. Txawm tias tsis muaj kev ua tiav ntxiv, nws qhov chaw ua haujlwm tseem ruaj khov. Cov txiaj ntsig zoo sib xws tau tshaj tawm los ntawm EPFL, Harvard, thiab Zhejiang University. Txawm li cas los xij, qhov kev sib piv feem ntau siv cov modulators LNOI tsis kho, uas tej zaum yuav tsis ncaj ncees tag nrho; nrog kev ua tiav, kev ua tau zoo ntawm ob qho khoom siv yuav zoo sib xws. Qhov sib txawv tseem ceeb yog LTOI xav tau tsawg dua cov kauj ruam ua tiav ntxiv.
②Birefringence qis dua: 0.004 vs 0.07
Qhov kev sib xyaw ua ke ntawm lithium niobate (LNOI) ntau dhau tuaj yeem ua rau muaj kev cov nyom ntau, tshwj xeeb tshaj yog thaum cov waveguide khoov tuaj yeem ua rau muaj kev sib txuas hom thiab kev sib xyaw hom. Hauv LNOI nyias nyias, qhov khoov hauv waveguide tuaj yeem hloov TE lub teeb mus rau hauv TM lub teeb ib feem, ua rau kev tsim cov khoom siv passive nyuaj, xws li cov lim dej.
Nrog LTOI, qhov birefringence qis dua tshem tawm qhov teeb meem no, ua rau nws yooj yim dua los tsim cov khoom siv passive ua haujlwm siab. EPFL kuj tau tshaj tawm cov txiaj ntsig zoo, siv LTOI qhov birefringence qis thiab tsis muaj hom-crossing los ua tiav ultra-wide-spectrum electro-optic frequency comb generation nrog kev tswj hwm dispersion tiaj tus hla ntau yam spectral. Qhov no ua rau muaj 450 nm comb bandwidth zoo kawg nkaus nrog ntau dua 2000 comb kab, ntau zaus loj dua qhov uas tuaj yeem ua tiav nrog lithium niobate. Piv rau Kerr optical frequency combs, electro-optic combs muab qhov zoo ntawm kev tsis muaj threshold thiab ruaj khov dua, txawm hais tias lawv xav tau lub zog microwave input siab.
③Qhov Kev Puas Tsuaj Zoo Dua ntawm Qhov Muag
Qhov kev puas tsuaj ntawm qhov muag ntawm LTOI yog ob npaug ntawm LNOI, muab qhov zoo dua hauv kev siv nonlinear (thiab tej zaum yav tom ntej Coherent Perfect Absorption (CPO) daim ntawv thov). Cov theem fais fab tam sim no ntawm cov khoom siv kho qhov muag tsis zoo li yuav ua rau lithium niobate puas tsuaj.
④Cov nyhuv Raman qis
Qhov no kuj tseem siv rau cov ntawv thov nonlinear. Lithium niobate muaj Raman effect muaj zog, uas hauv Kerr optical frequency comb applications tuaj yeem ua rau Raman lub teeb tsis xav tau thiab tau txais kev sib tw, tiv thaiv x-cut lithium niobate optical frequency combs kom tsis txhob mus txog lub xeev soliton. Nrog LTOI, Raman effect tuaj yeem raug tshem tawm los ntawm kev tsim crystal orientation, tso cai rau x-cut LTOI kom ua tiav soliton optical frequency comb generation. Qhov no ua rau muaj kev sib koom ua ke ntawm soliton optical frequency combs nrog high-speed modulators, ib qho feat tsis ua tiav nrog LNOI.
◆ Vim li cas ho tsis tau hais txog Thin-Film Lithium Tantalate (LTOI) ua ntej?
Lithium tantalate muaj qhov kub Curie qis dua li lithium niobate (610 ° C vs. 1157 ° C). Ua ntej txoj kev loj hlob ntawm heterointegration technology (XOI), lithium niobate modulators tau tsim los ntawm kev siv titanium diffusion, uas yuav tsum tau annealing ntawm ntau tshaj 1000 ° C, ua rau LTOI tsis haum. Txawm li cas los xij, nrog rau kev hloov pauv niaj hnub no mus rau kev siv cov insulator substrates thiab waveguide etching rau modulator tsim, qhov kub Curie 610 ° C yog ntau dua li txaus.
◆ Puas Yog Thin-Film Lithium Tantalate (LTOI) Yuav Hloov Thin-Film Lithium Niobate (TFLN)?
Raws li kev tshawb fawb tam sim no, LTOI muaj cov txiaj ntsig zoo hauv kev ua haujlwm tsis siv neeg, kev ruaj khov, thiab tus nqi tsim khoom loj, tsis muaj qhov tsis zoo. Txawm li cas los xij, LTOI tsis dhau lithium niobate hauv kev ua haujlwm modulation, thiab cov teeb meem ruaj khov nrog LNOI muaj cov kev daws teeb meem paub. Rau kev sib txuas lus DR modules, muaj qhov xav tau tsawg kawg nkaus rau cov khoom siv tsis siv neeg (thiab silicon nitride tuaj yeem siv yog tias xav tau). Tsis tas li ntawd, kev nqis peev tshiab yuav tsum tau rov tsim cov txheej txheem wafer-level etching, cov txheej txheem heterointegration, thiab kev sim kev ntseeg siab (qhov nyuaj nrog lithium niobate etching tsis yog waveguide tab sis ua tiav cov txiaj ntsig siab wafer-level etching). Yog li ntawd, txhawm rau sib tw nrog lithium niobate txoj haujlwm tau tsim, LTOI yuav tsum tau tshawb pom cov txiaj ntsig ntxiv. Txawm li cas los xij, kev kawm, LTOI muaj peev xwm tshawb fawb tseem ceeb rau kev sib xyaw ua ke ntawm cov kab ke hauv-chip, xws li octave-spanning electro-optic combs, PPLT, soliton thiab AWG wavelength division devices, thiab array modulators.
Lub sijhawm tshaj tawm: Kaum Ib Hlis-08-2024