Ma hope o ka makahiki 1887, ua hāʻawi ʻo William Thomson physicist Scottish i kāna hiʻohiʻona geometric o ke ʻano o ka ether, kahi i manaʻo ʻia he ʻano ākea āpau, nā haʻalulu e hōʻike mai iā mākou he mau hawewe electromagnetic, me ka mālamalama. ʻOiai ka pau ʻole o ka manaʻo ether, ua hoʻomau ke ʻano geometric, a i ka makahiki 1993, hāʻawi ʻo Denis Ware lāua ʻo Robert Phelan i kahi hiʻohiʻona ʻoi aʻe o kahi hale e hiki ai ke hoʻopiha piha i ka nui. Mai ia manawa mai, makemake nui ʻia kēia ʻano hoʻohālike i ka poʻe makemakika a i ʻole nā mea pena kiʻi, akā ua hōʻike ʻia nā noiʻi hou e hiki ke hoʻokumu i ke kumu o nā ʻenehana e hiki mai ana e hoʻohana i ka māmā ma mua o ka uila. He aha ka ʻōhū Ware-Phelan, he aha ka mea ʻokoʻa, a pehea e hoʻohana ʻia ai e hopu i ka mālamalama? E loaʻa iā mākou nā pane i kēia a me nā nīnau ʻē aʻe ma ka hōʻike o ka hui noiʻi. Hele.
Kumu noiʻi
Literally i ka haneri makahiki aku nei i loko o ka 'epekema kaiaulu aia kekahi manaʻo hoihoi loa e pili ana i kekahi mea o na mea a puni. ʻO kēia kumumanaʻo i manaʻo e wehewehe i ke ʻano o nā hawewe electromagnetic. Ua manaʻo ʻia ua hoʻopuni ka ether i nā mea āpau a ʻo ia ke kumu o kēia mau nalu. ʻO nā ʻike ʻepekema i hahai i ke ʻano ether i luku loa iā ia.
William Thomson
Eia naʻe, i ka makahiki 1887, i ka wā i piha ai ka manaʻo o ka ether i ka ikaika a me ka kaulana, nui nā kānaka ʻepekema i hōʻike i ko lākou mau manaʻo e pili ana i ka hiki ʻana o ka ether ke hoʻopiha i nā wahi āpau. ʻO William Thomson, ʻo ia hoʻi ʻo Lord Kelvin, ʻaʻohe mea ʻē aʻe. E ʻimi ana ʻo ia i hale e hoʻopiha pono ai i ke ākea i ʻole he mau wahi kaawale. Ua kapa ʻia kēia hulina ʻo ka pilikia Kelvin.
He laʻana mua: e noʻonoʻo i kahi pahu i loko o nā kini cola. Ma waena o lākou, ma muli o ke ʻano cylindrical, puka mai nā voids, i.e. wahi hoʻohana ʻole ʻia.
ʻO Thomson, ma waho aʻe o ka manaʻoʻiʻo ʻaʻole i ʻoi aku ka honua ma mua o 40 miliona mau makahiki, ua manaʻo ʻo ia i kahi ʻano geometric hou, i hoʻomaikaʻi ʻia e Denis Ware lāua ʻo Robert Phelan, a no laila ua kapa ʻia ʻo ia ma hope o lākou.
Hoʻokumu ʻia ka hale ʻo Ware-Phelan ma luna o kahi honeycomb e hoʻopiha ana i ka hakahaka me ka polyhedra disjoint, me ka waiho ʻole ʻana i kahi hakahaka. ʻO ka honeycomb, ka mea a mākou e manaʻo mau ai he hexagons mahalo i ka honeycomb, hele maoli mai i nā ʻano like ʻole. Aia nā cubic, octahedral, tetrahedral, rhombic dodecahedral, etc.
Kūlana Ware-Phelan
ʻO ka mea maʻamau e pili ana i nā honeycombs Ware-Phelan ʻo ia ka mea i loaʻa i nā ʻano geometric like ʻole a me nā mea. Ma kona kumu, he hu'ahu'a maika'i ia o nā'ōmole like-nui.
ʻO ke kupuna o kēia huʻa, ʻo ia ka Haku Kelvin i ʻōlelo ai, i kamaʻāina mua iā mākou. Eia nō naʻe, ʻo kāna ʻano he mau honeycombs cubic pōkole. ʻO ka hale Kelvin he ʻano honeycomb convex like ʻole i hana ʻia e kahi octahedron i ʻoki ʻia, ʻo ia ka polyhedron (tetradecahedron) ʻehā mau alo, piha i ka hakahaka, me 6 mau maka huinaha a me 8 mau maka hex.
ʻO kēia koho no ka hoʻonui ʻana i ka hoʻopiha piha ʻana i manaʻo ʻia he kūpono no kahi kokoke i hoʻokahi haneli mau makahiki, a hiki i ka wehe ʻana o Ware lāua ʻo Phelan i kā lāua hale i ka makahiki 1993.
Pentagondodecahedron a me decahedron
ʻO ka ʻokoʻa nui ma waena o ka Ware-Phelan honeycomb a me kāna mea i hana mua ʻia, ʻo ia ka hoʻohana ʻana i ʻelua ʻano o nā mea constituent, akā naʻe, he like ka nui: he pentagondodecahedron (he dodecahedron me ka tetrahedral symmetry) a me ka 14hedron me ka rotational symmetry.
Ma ka hana a mākou e noʻonoʻo nei i kēia lā, ua hoʻoholo ka poʻe ʻepekema mai ke Kulanui ʻo Princeton e hoʻohana i ka pahu Ware-Phelan i nā photonics. ʻO ka mea mua, he mea pono e ʻike inā loaʻa i kēlā mau huʻa nā ʻāpana photonic band gaps (PBGs), ka mea e ālai ai i ka hoʻolaha ʻana o ka mālamalama ma nā ʻaoʻao āpau a no nā polarizations āpau ma luna o kahi ākea o nā alapine.
I kā lākou aʻo ʻana, ua hōʻike nā ʻepekema ʻo kahi pūnaewele photonic 16,9D e pili ana i ka pahu Ware-Phelan e alakaʻi i ka PBG nui (XNUMX%) me kahi kiʻekiʻe kiʻekiʻe. isotropy*, he waiwai nui ia no nā kaapuni photonic.
Isotropy* — mau waiwai kino like ma na aoao a pau.
Ua hana maikaʻi ʻo Kelvin foam a me C15 foam ma ke ʻano o ka PBG, akā ua haʻahaʻa lākou i ke ʻano o Ware-Phelan ma kēia ʻano.
Ua hana ʻia nā haʻawina like ma mua, akā ua kālele lākou i ka huʻa maloʻo ʻelua. A laila ua ʻike ʻia ʻelua mau ʻāpana maloʻo amorphous e hōʻike ana i ka PBG wale nō no ka polarization uila transverse. ʻO ka pilikia, aia ʻelua polarizations ma 3D foam.
ʻOiai nā pilikia e hiki mai ana, hiki ke manaʻo ʻia ʻo 30D foam he mea hoʻohiki i ke kahua o nā photonics, e like me nā mea noiʻi. Aia ke kumu o kēia: ʻO nā kānāwai o Plateau e hōʻoia i ka hana ʻana o nā kihi i nā vertices tetrahedral wale nō. A he mea nui kēia no nā pūnaewele photonic. ʻO kahi hiʻohiʻona koʻikoʻi o kēia he daimana me kahi PBG o XNUMX%.
Loa'a ka waiwai tetrahedral o ka lattice daimana i ka hu'ahu'a, akā 'oko'a kona mau 'ao'ao a me nā lō'ihi like 'ole. Ke waiho wale nei ka ʻike pehea a me ka nui o ka hopena o ia mau ʻokoʻa i nā waiwai photonic.
Inā ʻoi aku ka mānoanoa o nā iwi ʻaoʻao o ka pahu maloʻo 17D, hiki ke hana i nā ʻupena photonic (nā kiʻi ma lalo) e hōʻike ana i nā PBG photonic i haʻi ʻia a hiki i ka XNUMX%, hoʻohālikelike ʻia a ʻoi aku paha i nā hiʻohiʻona maʻamau o nā kristal photonic i hui pū ʻia.
Kiʻi #1: Loaʻa nā ʻupena pahu kiʻi kiʻi ma ka mānoanoa ʻana i nā ʻaoʻao o ka hale Ware-Phelan (hema), Kelvin structure (waena) a me C15 foam ('ākau).
No ka hoʻokō ʻana i ia ʻano hoʻohālike ma ka hoʻomaʻamaʻa, pono e hoʻoheheʻe mua ʻia ka pahu maloʻo a laila uhi ʻia me kahi mea dielectric. Ma keʻano maʻamau, ʻoi aku ka haʻahaʻa o ka PBG o ka foam ma mua o ke aniani photonic, akā hiki ke hoʻokō ʻia kēia hemahema e kekahi mau pono. ʻO ka mea mua, ʻo ka hoʻonohonoho ponoʻī ʻana o ka ʻūhā hiki ke ʻae i ka hana wikiwiki o nā laʻana nui. ʻO ka lua, ʻo nā heterostructures foam photonic, e pili ana i ka noiʻi mua, hiki ke loaʻa i kahi ākea ākea o nā noi.
Nā hopena noiʻi
ʻO ka mea mua, pono e aʻo i ka ʻōpala maloʻo, i wehewehe ʻia he minima kūloko o ka ʻāpana interfacial hoʻokaʻawale * e pili ana i nā kaohi o ka leo, no laila e mālama ka geometry hope i nā kānāwai o Plateau.
Tessellation* - ka hoʻokaʻawale ʻana i ka mokulele i nā ʻāpana ʻāpana e uhi pono i ka mokulele holoʻokoʻa me ka waiho ʻole ʻana i nā āpau.
No ke kūkulu ʻana i nā ʻūhā Ware-Phelan, Kelvin, a me C15, ua hoʻomaka nā ʻepekema me nā tessellations Voronoi paona no nā kristal BCC, A15, a i ʻole C15.
Kiʻi Voronoi
Ua koho ʻia nā ʻāpana i ke ʻano i loaʻa ka leo hoʻokaʻawale a pau.
Ua aʻo ʻia nā ʻupena i hoʻokumu ʻia mai nā ʻaoʻao curved o nā pua a mai nā kihi tessellation pololei o ko lākou mau mua. No ka loiloi ʻana i ka topology o nā ʻano pua a pau, helu helu kani*.
Nā helu kelepona (nā helu helu kani)*Hoʻokumu pinepine ʻia ka nānā ʻana i nā hiʻohiʻona topological o nā mea pūnaewele (nā wai, crystalline a i ʻole nā pūnaewele amorphous) ma luna o ka manaʻo kalakala me ka hoʻohana ʻana i nā nodes no nā mana a me nā mea paʻa no nā pilina interatomic. Hoʻoholo ʻia ka loaʻa ʻole a i ʻole ke ola ʻana o kahi pilina ma waena o nā nodes ʻelua ma ka nānā ʻana i nā hana o ka māhele radial piha a hapa o ka ʻōnaehana. I loko o ka ʻenehana pūnaewele, ua kapa ʻia kahi ʻano o nā nodes a me nā loulou i hoʻopili ʻia i ka moʻo me ka ʻole o ka uhi ʻana he ala. Ma hope o kēia wehewehe ʻana, he ala paʻa wale ke apo. Inā nānā pono ʻoe i kahi node pūnaewele kikoʻī, hiki iā ʻoe ke ʻike hiki i kēia node ke komo i nā apo he nui. Hoʻohālikelike ʻia kēlā me kēia apo e kona mau ʻāpana ponoʻī a hiki ke hoʻokaʻawale ʻia ma muli o nā pilina ma waena o nā nodes a me nā loulou e hana ai.
ʻO ke ala mua e wehewehe ai i ke apo na Shirley W. King. No ke aʻo ʻana i ka hoʻohui ʻana o ka aniani SiO2, wehewehe ʻo ia i ke apo ma ke ala pōkole loa ma waena o nā hoalauna ʻelua o kahi node i hāʻawi ʻia.
Ma ka hihia o ke aʻo ʻana e noʻonoʻo ʻia nei, ua helu ʻia ka helu o nā apo pōkole loa i kēlā me kēia vertex i loko o kahi pūnaehana.
He 2 mau huinaha a me 4 hexagons ma ka piko hoʻokahi keena o ke kŘkohu Kelvin, akā he mau helehelena pentagonal a hexagonal wale nō ka TCP (tetrahedrally close-packed) (nā awelika: 5.2 a me 0.78 ma Ware-Phelan foam; 5.3 a me 0.71 ma C15 foam). ʻO Voronoi tessellations A15 a me C15 nā hale TCP me ka helu nui a me ka liʻiliʻi loa o nā kihi (f) no 1 keena. No laila, ʻo ka ʻōnaehana Ware-Phelan ka nui o nā maka (f = 13 + 1/2), a ʻo C15 ka helu liʻiliʻi loa o nā maka (f = 13 + 1/3).
I ka pau ʻana o kā lākou hoʻomākaukau ʻana, ua hoʻomaka ka poʻe ʻepekema e hoʻohālike i kahi pūnaewele photonic e pili ana i nā iwi ʻaoʻao maloʻo, ʻo ia hoʻi. ʻupena kiʻi kiʻi. Ua ʻike ʻia ma kahi waiwai PBG o 20% ka hoʻokō ʻana o ka ʻōnaehana i hoʻonui ʻia, akā ma ka 15% e lilo ka pahu Ware-Phelan i paʻa. No kēia kumu, ʻaʻole i noʻonoʻo ka poʻe ʻepekema i ka ʻūhā pulu, kahi o nā palena o ka Plateau he tricuspid cross-sections. Akā, ʻo ka manaʻo nui ma luna o nā hale ʻūhā maloʻo, kahi e hiki ai i nā ʻepekema ke hoʻonui mālie i ka mānoanoa o nā iwi ʻaoʻao.
Eia kekahi, ʻo kēlā me kēia ʻaoʻao ka axis medial o ka spherocylinder (capsule), kahi o ka radius kahi ʻāpana hoʻokani.
Hoʻomanaʻo mai ka poʻe noiʻi iā mākou ʻaʻole ʻo ia mau ʻupena puaʻa ma ke ʻano maoli, akā no ka maʻalahi o kā lākou hōʻike e kapa ʻia lākou he "foam" a i ʻole "foam network."
I ka wā o ka simulation, ua mālama ʻia ka ʻāpana ɛ (dielectric contrast) - ka māhele o nā mea hoʻomau dielectric o nā mea me nā waiwai insulation kiʻekiʻe a haʻahaʻa. Manaʻo ʻia ka ʻokoʻa dielectric ma waena o 13 a me 1, ka mea maʻamau i hoʻohana ʻia i ka palapala ma ke ʻano he maʻamau i ka hoʻohālikelike ʻana i ka hana o nā hoʻolālā mea photonic like ʻole.
No kēlā me kēia pūnaewele, ua hoʻonui ʻia ka radius o nā ʻaoʻao (spherocylinders) no ka lakene kiʻekiʻe o ka ʻāpana band a me kona waena: ∆ω/ωm, kahi ∆ω ʻo ia ka laulā alapinepine, a ωm — ka pinepine i loko o ka ʻāpana.
Kiʻi #2: ʻO ke kinona kiʻi kiʻi o Ware-Phelan foam (ʻulaʻula), Kelvin foam (uliuli), a me C15 foam ('ōmaʻomaʻo).
A laila, ua ana ʻia nā nui PBG a ʻike ʻia: 7.7% no ka pahu Kelvin, 13.0% no ka pahu C15 a me 16.9% no ka pahu Ware-Phelan. Hoʻonui ka liʻiliʻi ʻāpana i ka nui PBG ma 0.7%, 0.3 a i ʻole 1.3%.
E like me ka maopopo ʻana mai ka nānā ʻana, ʻoi aku ka nui o nā PBG pūnaewele TCP ma mua o nā pūnaewele Kelvin. ʻO nā pūnaewele TCP ʻelua, ʻo Ware-Phelan foam ka nui o ka bandgap nui, ʻo ia paha ma muli o ka liʻiliʻi liʻiliʻi o ka lōʻihi o ka loulou. Manaʻo ka poʻe ʻepekema ʻo ka ʻokoʻa o nā lōʻihi pili i ke kumu nui i kā lākou ʻōnaehana, i.e. ma Ware-Phelan foam, ʻoi aku ka liʻiliʻi o ka PBG ma mua o ke daimana (31.6%) a i ʻole ma ka ʻōnaehana Laves (28.3%).
ʻO kahi hiʻohiʻona koʻikoʻi i ka photonics ka isotropy o PBG, kahi e hiki ai ke hana i nā alakaʻi nalu o ke ʻano like ʻole. ʻO nā quasicrystals Photonic, a me nā pūnaewele photonic amorphous, ʻoi aku ka isotropic ma mua o nā kristal photonic maʻamau.
ʻO ke ʻano o ka foam-photonic ma lalo o ke aʻo ʻana he kiʻekiʻe o ka isotropy. Aia ma lalo ke kumu no ka hoʻoholo ʻana i ka coefficient anisotropy (ʻo ia hoʻi, ke degere o ka ʻokoʻa i nā waiwai o kekahi kaiapuni) PBG (А):
A: = (√Var[ωHDB]+Var[ωLAB]) / ωm
Ua ʻike ʻia ka ʻūhā C15 he anisotropy haʻahaʻa loa (1.0%), a ukali ʻia e ka huʻa Weir-Phelan (1.2%). No laila, ua isotropic nui kēia mau hale.
Akā ʻo ka ʻōnaehana Kelvin e hōʻike ana i kahi coefficient anisotropy o 3.5%, kahi kokoke loa i ka ʻōnaehana Laves (3.4%) a me ke daimana (4.2%). Eia nō naʻe, ʻaʻole ʻoi aku ka maikaʻi o kēia mau hōʻailona, no ka mea, aia nō nā ʻōnaehana cubic maʻalahi me kahi coefficient anisotropy o 8.8% a me nā pūnaewele daimana hexagonal me 9.7%.
I ka hoʻomaʻamaʻa, i ka wā e pono ai e hoʻokō i ka waiwai PBG kiʻekiʻe, i kekahi manawa pono e hoʻololi i kekahi mau ʻāpana kino o ka hale. I kēia hihia, ʻo kēia ʻāpana ka radius o nā spherocylinders. Ua hana nā kānaka ʻepekema i nā helu makemakika kahi i hoʻoholo ai lākou i ka pilina ma waena o ke kāʻei kiʻi photonic a me kona laulā ma ke ʻano he hana. ɛ. No kēlā me kēia waiwai i loaʻa, ua hoʻonui ʻia ka radius e hoʻonui i ka ∆ω/ωm.
Kiʻi Helu 3: ka hoʻohālikelike o ∆ω/ωm o nā ʻupena pahu i aʻo ʻia (C15, Kelvin, Weir-Phelan) a me nā hale ʻē aʻe (diamond, hexagonal diamond, Laves, SC - cubic maʻamau).
Mālama ʻo Weir-Phelan foam i nā nui PBG ʻae ʻia o 8% a hiki i ka hoʻohālikelike dielectric ɛ≈9, a ua hoʻonui ʻia ka radius e hoʻokō i ka waiwai PBG kiʻekiʻe o 15%. Nalo nā PBG i ka wā ɛ < 6.5. E like me ka mea i manaʻo ʻia, ʻo ka hale daimana ka PBG nui loa ma waena o nā hale a pau i aʻo ʻia.
No ka ʻike kikoʻī hou aku me nā nuances o ke aʻo ʻana, manaʻo wau e nānā и iāia.
Epilogue
ʻO ke kumu nui o ka hoʻokō ʻana i kēia noiʻi ʻana ʻo ka makemake e pane i ka nīnau inā hiki i nā ʻoihana pua ke hōʻike i ka PBG piha. ʻO ka hoʻololi ʻana i nā ʻaoʻao o nā hale ʻūhā maloʻo i loko o nā pūnaewele photonic ua hōʻike ʻia hiki iā lākou.
I kēia manawa, ʻaʻole i hoʻopaʻa ʻia ka foam. ʻOiaʻiʻo, aia nā haʻawina e hāʻawi i nā hopena maikaʻi e pili ana i nā pūnaewele amorphous, akā ua lawe ʻia lākou ma nā mea liʻiliʻi loa. ʻAʻole maopopo ke ʻano o ka ʻōnaehana i ka piʻi ʻana o kona mau ana.
Wahi a nā mea kākau o ka noiʻi, ua wehe kā lākou hana i nā mea he nui no nā mea hou e hiki mai ana. He mea maʻamau ka foam ma ke ʻano a he maʻalahi ke hana ʻana, e hoʻohiwahiwa ana i kēia hale no nā hana pono.
Kāhea ka poʻe ʻepekema i ka Pūnaewele ʻo ia kekahi o nā noi nui loa o kā lākou noiʻi. E like me ka ʻōlelo a ka poʻe noiʻi, ʻaʻole hou ka hoʻouna ʻana i ka ʻikepili ma luna o ka fiber optical, akā hoʻololi mau ʻia ka māmā i uila ma kona wahi e hele ai. Hiki i nā mea ʻenehana bandgap Photonic ke kuhikuhi pololei i ka mālamalama ma mua o nā uwea fiber optic maʻamau a hiki ke lawelawe ma ke ʻano he transistors optical e hana i nā helu me ka hoʻohana ʻana i ka māmā.
No ka nani o nā hoʻolālā, nui nō ka hana e hana ʻia. Eia naʻe, ʻaʻole hiki i ka paʻakikī o ka hana noiʻi a me ka paʻakikī o ka hoʻokō ʻana i nā hoʻokolohua hiki ke lanakila i ka hoihoi o nā ʻepekema a me ko lākou makemake e hoʻomaikaʻi i ka honua o ka ʻenehana.
Mahalo no ka nānā ʻana, noho ʻimi a hauʻoli maikaʻi i ka hopena pule a pau! 🙂
Mahalo no kou noho pū ʻana me mākou. Makemake ʻoe i kā mākou ʻatikala? Makemake ʻoe e ʻike i nā mea hoihoi hou aʻe? E kākoʻo iā mākou ma ke kau ʻana i kahi kauoha a i ʻole ka ʻōlelo ʻana i nā hoaaloha, , 30% ho'ēmi no nā mea hoʻohana Habr ma kahi kūʻokoʻa kūʻokoʻa o nā kikowaena helu komo, i hana ʻia e mākou no ʻoe: (loaʻa me RAID1 a me RAID10, a hiki i 24 cores a hiki i 40GB DDR4).
ʻO Dell R730xd 2 mau manawa maʻalahi? Eia wale nō ma Netherlands! Dell R420 - 2x E5-2430 2.2Ghz 6C 128GB DDR3 2x960GB SSD 1Gbps 100TB - mai $99! Heluhelu e pili ana
Source: www.habr.com