ʻO nā mea lithium niobate kiʻi lahilahi a me ka modulator lithium niobate kiʻi lahilahi

Nā pōmaikaʻi a me ke koʻikoʻi o ka lithium niobate kiʻi ʻoniʻoni i loko o ka ʻenehana photon microwave

ʻenehana photon microwaveLoaʻa iā ia nā pōmaikaʻi o ka bandwidth hana nui, ikaika ka hana like ʻana a me ka haʻahaʻa haʻahaʻa haʻahaʻa haʻahaʻa, hiki ke wāwahi i ka bottleneck ʻenehana o ka ʻōnaehana microwave kahiko a hoʻomaikaʻi i ka hana o nā lako ʻike uila e like me ka radar, ke kaua uila, kamaʻilio a me ke ana a me ka mana. Eia nō naʻe, ʻo ka ʻōnaehana photon microwave e pili ana i nā ʻenehana discrete kekahi mau pilikia e like me ka nui o ka leo, ke kaumaha kaumaha a me ka paʻa maikaʻi ʻole, ka mea e kaohi nui ai i ka hoʻohana ʻana o ka ʻenehana photon microwave ma nā lewa a me ka lewa. No laila, ke lilo nei ka ʻenehana photon microwave i mea kākoʻo koʻikoʻi e wāwahi i ka noi ʻana o ka microwave photon i loko o ka ʻōnaehana ʻikepili uila a hāʻawi i ka pāʻani piha i nā pono o ka ʻenehana photon microwave.

I kēia manawa, ua lilo ka ʻenehana hoʻohui photonic i hoʻokumu ʻia i ka SI a me ka ʻenehana hoʻohui photonic i hoʻokumu ʻia e INP ma hope o nā makahiki o ka hoʻomohala ʻana i ke kahua o ka kamaʻilio optical, a ua hoʻokomo ʻia ka nui o nā huahana i ka mākeke. Eia naʻe, no ka hoʻohana ʻana i ka microwave photon, aia kekahi mau pilikia i kēia mau ʻano ʻenehana hoʻohui photon: no ka laʻana, ʻo ka coefficient electro-optical nonlinear o Si modulator a me InP modulator ke kūʻē i ka linearity kiʻekiʻe a me nā hiʻohiʻona ikaika nui i hahai ʻia e ka ʻenehana photon microwave; No ka laʻana, ʻo ka silicon optical switch e ʻike ana i ka hoʻololi ʻana i ke ala optical, inā paha e pili ana i ka hopena thermal-optical, piezoelectric hopena, a i ʻole ka hopena o ka lawe ʻana i ka dispersion, loaʻa nā pilikia o ka wikiwiki o ka hoʻololi ʻana, ka hoʻohana ʻana i ka mana a me ka hoʻohana ʻana i ka wela, ʻaʻole hiki ke hoʻokō i ka nānā ʻana i ke kukui wikiwiki a me ka nui o nā noi microwave photon.

ʻO Lithium niobate ke koho mua loa no ka wikiwiki kiʻekiʻeelectro-optic modulationnā mea waiwai ma muli o kāna hopena electro-optic linear maikaʻi loa. Eia naʻe, ʻo ka lithium niobate maʻamauelectro-optical modulatorhana ʻia me ka nui lithium niobate crystal material, a ʻo ka nui o ka hāmeʻa he nui loa, ʻaʻole hiki ke hoʻokō i nā pono o ka ʻenehana photon microwave. Pehea e hoʻohui ai i nā mea lithium niobate me ka linear electro-optical coefficient i loko o ka ʻōnaehana ʻenehana photon microwave i hoʻohui ʻia i ka pahuhopu o nā mea noiʻi kūpono. I ka makahiki 2018, ua hōʻike mua kahi hui noiʻi mai ke Kulanui ʻo Harvard ma ʻAmelika Hui Pū ʻIa i ka ʻenehana hoʻohui photonic e pili ana i ka lithium niobate kiʻi ʻoniʻoni ma Nature, no ka mea, ʻo ka ʻenehana i nā pono o ka hoʻohui kiʻekiʻe, ka bandwidth modulation electro-optical nui, a me ka linearity kiʻekiʻe o ka hopena electro-optical, hoʻokahi i hoʻokuʻu ʻia, ua hoʻomaka koke ia i ka hoʻonaʻauao a me ka ʻoihana ʻenehana i ke kula o ka photonic integration a me ka microwave photonic. Mai ka hiʻohiʻona o ka noi ʻana i ka microwave photon, ke nānā nei kēia pepa i ka mana a me ke koʻikoʻi o ka ʻenehana hoʻohui photon e pili ana i ka lithium niobate kiʻi ʻoniʻoni ma ka hoʻomohala ʻana i ka ʻenehana photon microwave.

ʻO nā mea lithium niobate kiʻi lahilahi a me nā kiʻi lahilahilithium niobate modulator
I nā makahiki ʻelua i hala iho nei, ua puka mai kahi ʻano mea hou o ka lithium niobate, ʻo ia hoʻi, ua exfoliated ka kiʻi lithium niobate mai ka nui o ka lithium niobate crystal ma ke ʻano o ka "ion slicing" a hoʻopaʻa ʻia i ka wafer Si me kahi papa silica buffer e hoʻokumu ai i LNOI (LiNbO3-On-Insulator) mea [5], i kapa ʻia ʻo ka mea liʻiliʻi liʻiliʻi. Hiki ke kiʻi ʻia nā alakaʻi nalu Ridge me ke kiʻekiʻe ma mua o 100 nanometers ma luna o nā mea lithium niobate kiʻi ʻoniʻoni ʻoniʻoni ma o ke kaʻina hana etching maloʻo maloʻo, a ʻo ka ʻokoʻa ʻokoʻa refractive kūpono o nā alakaʻi nalu i hana ʻia hiki ke piʻi aku ma mua o 0.8 (ʻoi aku ka kiʻekiʻe ma mua o ka ʻokoʻa ʻokoʻa refractive index o ka lithium niobate waveguides kahiko o 0.02), e like me ka mea i hōʻike ʻia ma ka Figure ikaika. kahua māmā me ke kahua microwave i ka hoʻolālā ʻana i ka modulator. No laila, ʻoi aku ka maikaʻi o ka loaʻa ʻana o ka haʻahaʻa haʻahaʻa haʻahaʻa haʻahaʻa haʻahaʻa haʻahaʻa a me ka bandwidth modulation ʻoi aku ka lōʻihi.

ʻO ka hiʻohiʻona o ka haʻahaʻa haʻahaʻa lithium niobate submicron waveguide e haki i ka bottleneck o ka uila hoʻokele kiʻekiʻe o ka lithium niobate electro-optic modulator. Hiki ke hoʻemi ʻia ka spacing electrode i ~ 5 μm, a ua hoʻonui nui ʻia ka overlap ma waena o ke kahua uila a me ke kahua mode optical, a ua emi ka vπ ·L mai ka 20 V·cm a i lalo o 2.8 V·cm. No laila, ma lalo o ka hapalua hawewe like, hiki ke hoʻemi nui ʻia ka lōʻihi o ka mea hoʻohālikelike me ka modulator kuʻuna. I ka manawa like, ma hope o ka hoʻonui ʻana i nā ʻāpana o ka laulā, ka mānoanoa a me ka wā o ka electrode nalu hele, e like me ka mea i hōʻike ʻia ma ke kiʻi, hiki i ka modulator ke loaʻa ka mana o ka bandwidth modulation ultra-kiʻekiʻe ma mua o 100 GHz.

Fig.1 （a） ka hoʻohele ʻana i ke ʻano helu a me （b） kiʻi o ka ʻāpana kea o ka alakaʻi nalu LN.

Fig.2 （a） Waveguide and electrode structure and （b） coreplate of LN modulator

ʻO ka hoʻohālikelike ʻana i nā modulators lithium niobate kiʻi ʻoniʻoni me nā modulators pāʻoihana lithium niobate, nā modulators-based silicon a me nā modulators indium phosphide (InP) a me nā modulators electro-optical kiʻekiʻe kiʻekiʻe e kū nei, ʻo nā ʻāpana nui o ka hoʻohālikelike ʻana:
(1) Hapa-halu volt-lōʻihi huahana (vπ ·L, V·cm), ana i ka pono modulation o ka modulator, ka liʻiliʻi o ka waiwai, ʻoi aku ka kiʻekiʻe o ka pono modulation;
(2) 3 dB modulation bandwidth (GHz), e ana i ka pane o ka modulator i ka modulation kiʻekiʻe;
(3) Nalo hoʻokomo ʻia (dB) ma ka ʻāpana modulation. Hiki ke ʻike ʻia mai ka papa ʻaina ʻo ka ʻoniʻoni ʻoniʻoni lithium niobate modulator i loaʻa nā pōmaikaʻi i ka bandwidth modulation, ka hapalua hawewe, ka nalowale o ka interpolation optical a pēlā aku.

ʻO Silicon, e like me ka pōhaku kihi o ka optoelectronics i hoʻohui ʻia, ua hoʻomohala ʻia a hiki i kēia manawa, ua oʻo ke kaʻina hana, ʻo kona miniaturization ka mea kūpono i ka hoʻohui nui ʻana o nā mea hana / passive, a ua aʻo nui ʻia kona modulator i ke kahua o ka kamaʻilio optical. ʻO ka mīkini hoʻololi electro-optical o ke silika ka mea nui o ka lawe ʻana i ka depling-tion, ka lawe ʻana a me ka hōʻiliʻili lawe. Ma waena o lākou, ʻoi aku ka maikaʻi o ka bandwidth o ka modulator me ka linear depletion carrier depletion mechanism, akā no ka mea, ʻoi aku ka nui o ka māhele ʻana o ka optical field me ka like ʻole o ka ʻāpana depletion, e hoʻolauna kēia hopena i ka distortion nonlinear second-order distortion a me nā huaʻōlelo intermodulation distortion ʻekolu, i hui pū ʻia me ka hopena absorption o ka mea lawe i ke kukui, e alakaʻi ai i ka hōʻemi ʻana i ka hōʻailona o ka optical modulator.

He mau hopena electro-optical ko ka InP modulator, a hiki i ka multi-layer quantum well structure ke hoʻomaopopo i ka ultra-high rate a me ka haʻahaʻa hoʻokele uila modulators me Vπ·L a hiki i 0.156V · mm. Eia nō naʻe, ʻo ka hoʻololi ʻana o ka index refractive me ke kahua uila e pili ana i nā huaʻōlelo linear a me nā huaʻōlelo nonlinear, a ʻo ka hoʻonui ʻana i ka ikaika o ke kahua uila e ʻike nui ʻia ka hopena o ke kauoha lua. No laila, pono e hoʻopili i nā modulators electro-optic silicon a me InP e hoʻokumu i ka hui pn i ka wā e hana ai lākou, a na ka hui pn e lawe mai i ka nalowale absorption i ka mālamalama. Eia naʻe, liʻiliʻi ka nui modulator o kēia mau mea ʻelua, ʻo ka nui modulator InP pāʻoihana ʻo 1/4 o ka modulator LN. ʻO ka maikaʻi o ka modulation kiʻekiʻe, kūpono no ke kiʻekiʻe kiʻekiʻe a me ka lōʻihi pōkole digital optical transmission network e like me nā kikowaena data. ʻO ka hopena electro-optical o ka lithium niobate ʻaʻohe māmā absorption mechanical a me ka haʻahaʻa haʻahaʻa, kūpono ia no ka lōʻihi lōʻihi.kamaʻilio ʻike makame ka mana nui a me ka uku kiʻekiʻe. I loko o ka noi microwave photon, nā electro-optical coefficients o Si a me InP he nonlinear, ʻaʻole kūpono ia no ka ʻōnaehana photon microwave e ʻimi nei i ka linearity kiʻekiʻe a me nā dynamics nui. He kūpono loa ka mea lithium niobate no ka noi ʻana i ka microwave photon ma muli o kāna ʻano hoʻololi electro-optic modulation coefficient.