Ifilimu encinci ye-lithium niobate kunye nefilimu encinci ye-lithium niobate modulator

Izinto eziluncedo kunye nokubaluleka kwefilimu ebhityileyo i-lithium niobate kwitekhnoloji edibeneyo ye-microwave photon

Itekhnoloji yefoton yeMicrowaveineengenelo ze-bandwidth enkulu yokusebenza, isakhono esinamandla sokusebenza ngokunxuseneyo kunye nelahleko ephantsi yothumelo, enesakhono sokuphula ibhotile yobugcisa benkqubo ye-microwave yemveli kunye nokuphucula ukusebenza kwezixhobo zolwazi zomkhosi zombane ezifana nerada, imfazwe yombane, unxibelelwano kunye nokulinganisa kunye ulawulo. Nangona kunjalo, inkqubo yefoton ye-microwave esekwe kwizixhobo ezicacileyo ineengxaki ezithile ezifana nomthamo omkhulu, ubunzima obunzima kunye nozinzo olulambathayo, oluthintela ngokunzulu ukusetyenziswa kobuchwepheshe be-microwave photon kumaqonga asemkhathini kunye nasemoyeni. Ke ngoko, itekhnoloji yefoton ye-microwave ehlanganisiweyo iba yinkxaso ebalulekileyo yokwaphula usetyenziso lwefoton ye-microwave kwinkqubo yolwazi yombane yomkhosi kwaye inike ukudlala ngokupheleleyo kwiingenelo zobuchwepheshe be-microwave photon.

Okwangoku, itekhnoloji ye-SI-based photonic integration technology kunye ne-INP-based photonic integration technology iye yakhula ngakumbi emva kweminyaka yophuhliso kwinkalo yonxibelelwano lwe-optical, kwaye zininzi iimveliso ezifakwe kwimarike. Nangona kunjalo, usetyenziso lwefoton ye-microwave, kukho iingxaki kwezi ntlobo zimbini zetekhnoloji yokudityaniswa kwe-photon: umzekelo, i-nonlinear electro-optical coefficient ye-Si modulator kunye ne-InP modulator ichasene nomgca ophezulu kunye neempawu ezinkulu ezinamandla ezilandelwa yi-microwave. iteknoloji yefoton; Umzekelo, iswitshi ye-silicon optical eqonda ukutshintsha kwendlela yokubona, nokuba isekwe kwimpembelelo ye-thermal-optical, i-piezoelectric effect, okanye i-carrier injection dispersion effect, ineengxaki zesantya sokutshintsha okucothayo, ukusetyenziswa kwamandla kunye nokusetyenziswa kobushushu, obungenako ukuhlangabezana nokukhawuleza. ukuskena kwe-beam kunye nosetyenziso olukhulu lweefoton ze-microwave.

I-Lithium niobate ibisoloko ilukhetho lokuqala kwisantya esiphezuluukumodareyitha kwe-electro-opticizixhobo ngenxa yempembelelo yayo ebalaseleyo ye-electro-optic. Nangona kunjalo, i-lithium niobate yendabukoimodyuli ye-electro-opticalyenziwe ngezinto ezinkulu ze-lithium niobate crystal, kwaye ubungakanani besixhobo bukhulu kakhulu, obungenako ukukhawulelana neemfuno zetekhnoloji edibeneyo ye-microwave photon. Indlela yokudibanisa izinto ze-lithium niobate kunye ne-linear electro-optical coefficient kwi-microwave edibeneyo ye-teknoloji ye-photon inkqubo ibe yinjongo yabaphandi abafanelekileyo. Ngo-2018, iqela lophando elivela kwiYunivesithi yaseHarvard eUnited States liqale labika itekhnoloji yokudibanisa ifotonic esekelwe kwifilimu encinci ye-lithium niobate kwiNdalo, kuba iteknoloji ineenzuzo zokudityaniswa okuphezulu, i-electro-optical modulation bandwidth, kunye nomgca ophezulu we-electro. -impembelelo ye-optical, yakuba iqalisiwe, yabangela ngokukhawuleza ingqalelo yezemfundo kunye nezoshishino kwintsimi yokuhlanganiswa kweefotoni kunye neefotoni ze-microwave. Ngokwembono yesicelo se-microwave photon, eli phepha liphonononga impembelelo kunye nokubaluleka kobuchwepheshe bokuhlanganiswa kwefotoni esekwe kwifilimu ebhityileyo ye-lithium niobate kuphuhliso lwetekhnoloji ye-microwave photon.

Ifilimu encinci ye-lithium niobate kunye nefilimu encinciimodyuli ye-lithium niobate
Kwiminyaka emibini yakutshanje, uhlobo olutsha lwezinto ze-lithium niobate luye lwavela, oko kukuthi, ifilimu ye-lithium niobate ikhutshwe kwikristale enkulu ye-lithium niobate ngendlela "yokunqunyulwa kwe-ion" kwaye ibophelelwe kwi-Si wafer kunye ne-silica buffer layer. ifom ye-LNOI (i-LiNbO3-On-Insulator) impahla [5], ebizwa ngokuba yifilimu encinci ye-lithium niobate impahla kweli phepha. I-Ridge waveguides enobude obungaphezulu kwe-nanometers engaphezulu kwe-100 inokubekwa kwifilim ebhityileyo ye-lithium niobate ngenkqubo yogcino eyomileyo, kwaye umahluko osebenzayo wesalathiso se-refractive ye-waveguides eyenziweyo unokufikelela ngaphezulu kwe-0.8 (iphezulu kakhulu kunomahluko wesalathiso se-refractive yemveli. i-lithium niobate waveguides ye-0.02), njengoko kubonisiwe kwi-Figure 1. I-waveguide ethintelweyo kakhulu yenza kube lula ukufanisa ibala lokukhanya kunye nebala le-microwave xa uyila imodyuli. Ke, kuluncedo ukufezekisa i-voltage esezantsi yesiqingatha-amaza kunye ne-bandwidth enkulu yokumodareyitha kubude obufutshane.

Imbonakalo yelahleko ephantsi ye-lithium niobate i-submicron waveguide yophula ibhotile ye-voltage ephezulu yokuqhuba ye-lithium niobate electro-optic modulator. Izithuba ze-electrode zingancitshiswa zibe ~ 5 μm, kwaye ukugqithelana phakathi kwentsimi yombane kunye nentsimi ye-optical mode yanda kakhulu, kwaye i-vπ · L iyancipha ukusuka ngaphezu kwe-20 V · cm ukuya ngaphantsi kwe-2.8 V · cm. Ke ngoko, phantsi kombane ofanayo wesiqingatha-amaza, ubude besixhobo bunokuncitshiswa kakhulu xa kuthelekiswa nemodyuli yemveli. Kwangaxeshanye, emva kokuphucula iiparamitha zobubanzi, ubukhulu kunye nekhefu le-electrode ehambayo, njengoko kubonisiwe kulo mzobo, imodyuli inokuba namandla okumodareyitha okungaphezulu kwe-100 GHz.

Umzobo.1 (a) ubalo lwendlela yokusasazwa kunye (b) nomfanekiso wecandelo elinqamlezayo le-LN waveguide

Umzobo 2 (a) i-Waveguide kunye nesakhiwo se-electrode kunye (b) ne-coreplate ye-modulator ye-LN

Ukuthelekiswa kweemodyuli zefilimu ezicekethekileyo ze-lithium niobate kunye neemodyuli zentengiso ze-lithium niobate, iimodyuli ezisekwe kwisilicon kunye neemodyuli ze-indium phosphide (InP) kunye nezinye iimodyuli ezikhoyo ezinesantya esiphezulu se-electro-optical, iiparamitha eziphambili zothelekiso ziquka:
(1) Imveliso yobude besiqingatha sobude be-volt (vπ ·L, V·cm), ukulinganisa ukumodareyitha kobuchule bomodareyitha, okukhona kuncinci ixabiso, kokukhona kuphezulu ukumodareyitha ukusebenza kakuhle;
(2) I-3 dB i-modulation bandwidth (GHz), elinganisa impendulo ye-modulator kwi-high-frequency modulation;
(3) Ilahleko yokufaka i-Optical (dB) kwindawo yokumodareyitha. Inokubonwa kwitheyibhile ukuba ifilimu encinci ye-lithium niobate modulator ineenzuzo ezicacileyo kwi-modulation bandwidth, i-half-wave voltage, ilahleko ye-optical interpolation njalo njalo.

I-silicon, njengelitye lembombo le-optoelectronics edibeneyo, sele iphuhlisiwe ngoku, inkqubo ikhulile, i-miniaturization yayo ihambelana nokuhlanganiswa okukhulu kwezixhobo ezisebenzayo / ezingabonakaliyo, kwaye i-modulator yayo iye yafundiswa ngokubanzi kwaye yafundwa ngokunzulu kwintsimi ye-optical. unxibelelwano. I-electro-optical modulation mechanism ye-silicon yeyona nto ithwala i-depling-tion, inaliti ye-carrier kunye nokuqokelela kwe-carrier. Phakathi kwabo, i-bandwidth ye-modulator ilungile kunye ne-linear degree carrier depletion mechanism, kodwa ngenxa yokuba i-optical field distribution overlapping kunye ne-non-uniformity yengingqi yokunciphisa, esi siphumo siya kwazisa ukugqwesa okungahambi kakuhle kwe-second-order kunye nokuphazamiseka kwe-intermodulation. imigaqo, idityaniswe nefuthe lokufunxa lomthwali ekukhanyeni, okuya kukhokelela ekuncitshisweni kwe-optical modulation amplitude kunye nokuphazamiseka komqondiso.

I-modulator ye-InP ineempembelelo ezibalaseleyo ze-electro-optical, kunye ne-multi-layer quantum well structure inokuqonda i-ultra-high rate kunye ne-low drive modulators yombane kunye ne-Vπ · L ukuya kwi-0.156V · mm. Nangona kunjalo, ukuhluka kwesalathisi se-refractive kunye nentsimi yombane kubandakanya imigqaliselo yomgca kunye neyokungahambelani, kwaye ukwanda kombane wombane kuya kwenza umphumo wesibini uvelele. Ke ngoko, isilicon kunye ne-InP electro-optic modulators kufuneka zisebenzise i-bias ukwenza i-pn junction xa zisebenza, kwaye i-pn junction iya kuzisa ilahleko yokufunxa ekukhanyeni. Nangona kunjalo, ubungakanani bemodyuli yezi zimbini zincinci, ubungakanani bemodyuli ye-InP yorhwebo yi-1/4 yemodyuli ye-LN. Ukusebenza kakuhle kokumodareyitha, kukulungele ukuxinana okuphezulu kunye nomgama omfutshane uthungelwano lwedijithali lothungelwano lwedijithali olufana namaziko edatha. Impembelelo ye-electro-optical ye-lithium niobate ayinayo indlela yokufunxa ukukhanya kunye nelahleko ephantsi, efanelekileyo kumgama omde ohambelanayo.unxibelelwano lwamehlongomthamo omkhulu kunye nezinga eliphezulu. Kwisicelo se-microwave photon, i-electro-optical coefficients ye-Si kunye ne-InP ayinayo i-nonlinear, engafanelekanga kwi-microwave photon system eqhuba umgca ophezulu kunye ne-dynamics enkulu. Izinto ze-lithium niobate zifanelekile kakhulu kwisicelo se-microwave photon ngenxa ye-coefficient yayo ye-electro-optic modulation coefficient.