O se tasi o meatotino sili ona tāua o se modulator opitika o lona saoasaoa o le modulation poʻo le bandwidth, lea e tatau ona vave tutusa ma le saoasaoa o mea eletise o loʻo maua. O transistors o loʻo i ai le tele o felauaiga e sili atu i le 100 GHz ua uma ona faʻaalia i le tekinolosi silicon 90 nm, ma o le a faʻateleina atili le saoasaoa pe a faʻaitiitia le laʻititi o le foliga [1]. Peitaʻi, o le bandwidth o modulators faʻavae i le silicon i aso nei e faʻatapulaʻaina. E leai se χ(2)-nonlinearity o le Silicon ona o lona fausaga crystalline centro-symmetric. O le faʻaaogaina o le strained silicon ua iʻu ai i ni taunuuga manaia [2], ae o nonlinearities e leʻi faʻatagaina ai ni masini aoga. O lea la, o loʻo faʻalagolago pea silicon photonic modulators faʻaonaponei i le free-carrier dispersion i pn poʻo pin junctions [3–5]. Ua faʻaalia o forward biased junctions e faʻaalia ai se oloa voltage-length e maualalo e pei o le VπL = 0.36 V mm, ae o le saoasaoa o le modulation e faʻatapulaʻaina e le dynamics o minority carriers. Ae ui i lea, o fua faatatau o faʻamaumauga e 10 Gbit/s ua faʻatupuina i le fesoasoani a le faʻamamafa muamua o le faʻailoga eletise [4]. I le faʻaaogaina o fesoʻotaʻiga faʻafeagai, ua faʻateleina le bandwidth i le tusa ma le 30 GHz [5,6], ae o le oloa o le voltagelength na siʻitia i le VπL = 40 V mm. Ae paga lea, o ia plasma effect phase modulators e gaosia ai le modulation o le malosi e le manaʻomia [7], ma latou te tali atu e le laina i le voltage faʻaaogaina. Ae ui i lea, o faʻatulagaga faʻaleleia atili e pei o le QAM e manaʻomia ai se tali laina ma le pure phase modulation, ma avea ai le faʻaaogaina o le electro-optic effect (Pockels effect [8]) e matua manaʻomia lava.
2. Faiga SOH
Talu ai nei, ua fautuaina le auala e fa'aaogaina ai le silicon-organic hybrid (SOH) [9–12]. O se fa'ata'ita'iga o se SOH modulator o lo'o fa'aalia i le Ata 1(a). E aofia ai se slot waveguide e ta'ita'ia ai le optical field, ma ni silicon strips se lua e fa'afeso'ota'i fa'aeletise ai le optical waveguide i electrodes u'amea. O electrodes o lo'o i fafo atu o le optical modal field e 'alo'ese ai mai le optical losses [13], Ata 1(b). O le masini ua ufiufiina i se mea fa'aola eletise-optic lea e fa'atumuina tutusa ai le slot. O le modulating voltage e feavea'i e le metallic electrical waveguide ma pa'u'ū ifo i luga o le slot fa'afetai i le conductive silicon strips. Ona suia lea e le electric field le index of refraction i le slot e ala i le ultra-fast electro-optic effect. Talu ai o le slot e lautele i le fa'atonuga o le 100 nm, o ni nai volts e lava lea e fa'atupu ai ni modulating fields malolosi tele e tutusa ma le malosi dielectric o le tele o meafaitino. O le fausaga e maualuga le modulation efficiency talu ai o lo'o fa'apotopoto uma le modulating ma le optical fields i totonu o le slot, Ata 1(b) [14]. E moni, o faʻatinoga muamua o SOH modulators ma le sub-volt operation [11] ua uma ona faʻaalia, ma ua faʻaalia le sinusoidal modulation e oʻo atu i le 40 GHz [15,16]. Peitaʻi, o le luʻitau i le fausiaina o le maualalo-voltage high-speed SOH modulators o le fatuina lea o se connecting strip e maualuga le conductivity. I se equivalent circuit, e mafai ona faʻatusalia le slot e se capacitor C ma conductive strips e resistors R, Fig. 1(b). O le RC time constant e tutusa e fuafua ai le bandwidth o le masini [10,14,17,18]. Ina ia faʻaitiitia le resistance R, ua fautuaina e faʻapipiʻi le silicon strips [10,14]. E ui o le doping e faʻateleina ai le conductivity o silicon strips (ma o lea e faʻateleina ai le optical losses), e totogi e se tasi se faʻasalaga faʻaopoopo o le gau ona o le electron mobility e faʻaleagaina e le impurity scattering [10,14,19]. E le gata i lea, o taumafaiga lata mai o le gaosiga na faʻaalia ai le maualalo o le conductivity e leʻi mafaufauina.
O le Beijing Rofea Optoelectronics Co., Ltd. o loʻo i le "Silicon Valley" a Saina - Beijing Zhongguancun, o se kamupani tekonolosi maualuga ua tuuto atu i le auauna atu i faʻalapotopotoga suʻesuʻega i totonu ma fafo, faʻalapotopotoga suʻesuʻega, iunivesite ma tagata faigaluega suʻesuʻega faasaienisi faʻapisinisi. O la matou kamupani e tele lava ina faʻatinoina suʻesuʻega tutoʻatasi ma atinaʻe, mamanu, gaosiga, faʻatau atu oloa optoelectronic, ma tuʻuina atu fofo fou ma auaunaga faʻapolofesa ma faʻapitoa mo tagata suʻesuʻe faasaienisi ma inisinia tau alamanuia. Ina ua mavae tausaga o le faʻafouga tutoʻatasi, ua fausia ai se faʻasologa mauoa ma lelei atoatoa o oloa photoelectric, lea e faʻaaogaina lautele i pisinisi a le malo, militeri, felauaiga, eletise, tupe, aʻoaʻoga, fomaʻi ma isi pisinisi.
Matou te tulimatai atu i le galulue faʻatasi ma oe!
Taimi na lafoina ai: Mati-29-2023