Ọtụtụ ndị na-egwu egwuregwu gburugburu ụwa bụ ndị nwetagoro oge Xbox 360 maara nke ọma ọnọdụ mgbe njikwa ha ghọrọ ite frying nke ha nwere ike frying na akwa. Ọnọdụ dị otú ahụ dị mwute na-eme ọ bụghị nanị na consoles egwuregwu, kamakwa na ekwentị, laptọọpụ, mbadamba na ọtụtụ ihe ndị ọzọ. Na ụkpụrụ, ihe fọrọ nke nta ka ọ bụrụ ngwaọrụ eletrọnịkị ọ bụla nwere ike ịnweta ujo thermal, nke nwere ike iduga ọ bụghị naanị na ọdịda ya na iwe nke onye nwe ya, kamakwa na "ọganihu ọjọọ" nke batrị na nnukwu mmerụ ahụ. Taa, anyị ga-amata ọmụmụ ihe nke ndị ọkà mmụta sayensị na Mahadum Stanford, dị ka Nick Fury si na-atọ ọchị, mepụtara ọta nke na-echebe akụkụ electronic ndị na-ekpo ọkụ ọkụ site na ikpo ọkụ na, n'ihi ya, na-egbochi mmebi ha. Kedu ka ndị ọkà mmụta sayensị siri nwee ike ịmepụta ọta okpomọkụ, kedu ihe bụ isi ihe ya na otú ọ dị irè? Anyị na-amụta maka nke a na ihe ndị ọzọ site na akụkọ nke otu nyocha. Gaa.
Ntọala nyocha
A mara nsogbu nke ikpo oke ọkụ ruo ogologo oge, ndị ọkà mmụta sayensị na-edozi ya n'ụzọ dịgasị iche iche. Ụfọdụ n'ime ihe ndị kasị ewu ewu bụ iji iko, plastik na ọbụna n'ígwé nke ikuku, nke na-eje ozi dị ka ụdị mkpuchi nke radieshon thermal. N'ime eziokwu nke oge a, enwere ike imeziwanye usoro a site n'ibelata ọkpụrụkpụ nke oyi akwa nchebe na ọtụtụ atom na-enweghị atụfu ihe mkpuchi ọkụ ya. Nke ahụ bụ kpọmkwem ihe ndị nchọpụta ahụ mere.
N'ezie, anyị na-ekwu maka nanomaterials. Otú ọ dị, ojiji ha na-ekpo ọkụ na-ekpo ọkụ bụ ihe mgbagwoju anya na mbụ n'ihi na ogologo ikuku nke coolants (phonon*) dị mkpụmkpụ nke ukwuu karịa nke elektrọn ma ọ bụ foton.
Fonon* - ihe dị iche iche, nke bụ ọnụ ọgụgụ nke mmegharị mkpọtụ nke atọm kristal.
Tụkwasị na nke ahụ, n'ihi ọdịdị bosonic nke phonons, ọ gaghị ekwe omume ijikwa ha site na voltaji (dị ka a na-eme ya na ndị na-ebu ụgwọ), nke na-emekarị ka ọ sie ike ịchịkwa nnyefe okpomọkụ na ihe siri ike.
Na mbụ, ihe ndị na-ekpo ọkụ nke ihe siri ike, dị ka ndị nchọpụta na-echetara anyị, na-achịkwa site na fim nanolaminate na superlatices n'ihi nsogbu nhazi na nnukwu njupụta dị elu, ma ọ bụ site na silicon na germanium nanowires n'ihi ike ịgbasa phonon.
N'ọtụtụ ụzọ mkpuchi ọkụ nke akọwara n'elu, ndị ọkà mmụta sayensị ji obi ike dị njikere ịkọwapụta ihe dị n'akụkụ abụọ, nke ọkpụrụkpụ ya adịghị agafe ọtụtụ atom, nke na-eme ka ọ dị mfe ịchịkwa n'ọtụtụ atom. N'ime ọmụmụ ihe ha, ha ji van der Waals (vdW) Mgbakọ nke akwa 2D dị gịrịgịrị iji nweta nguzogide okpomọkụ dị elu n'oge usoro heterostructure ha.
Ndị agha Van der Waals * - ike mmekọrịta intermolecular / interatomic nwere ike nke 10-20 kJ / mol.
Usoro ọhụrụ ahụ mere ka o kwe omume ịnweta nguzogide okpomọkụ na vdW heterostructure na ọkpụrụkpụ nke 2 nm, tụnyere nke ahụ na oyi akwa nke SiO2 (silicon dioxide) na ọkpụrụkpụ nke 300 nm.
Tụkwasị na nke ahụ, iji vdW heterostructures emewo ka o kwe omume ịnweta njikwa ọkụ na ọkwa atomiki site na nhazi nke XNUMXD monolayers dị iche iche nwere ụdị njupụta atọ dị iche iche na ụdị vibrational.
Ya mere, ka anyị ghara ịdọrọ ụfụ nke pusi ma ka anyị malite ịtụle nsonaazụ nke nchọpụta a dị ịtụnanya.
Nsonaazụ nyocha
Nke mbụ, ka anyị mata njirimara microstructural na anya nke vdW heterostructures ejiri mee ihe n'ọmụmụ ihe a.
Foto #1
Na onyonyo a 1 na-egosi eserese akụkụ nke akụkụ anọ nke heterostructure nke nwere (site n'elu ruo na ala): graphene (Gr), MoSe2, MoS2, WSe22 na mkpụrụ SiO2/Si. Iji nyochaa ọkwa niile n'otu oge, jiri Raman laser* na ogologo ebili mmiri nke 532 nm.
Raman laser* - ụdị nke laser nke isi usoro nke mmụba ọkụ bụ ịgbasa Raman.
Raman gbasasịa, N'aka nke ya, bụ mgbasa nke na-adịghị ahụkebe nke radieshon anya na ụmụ irighiri ihe, nke na-esonyere mgbanwe dị ịrịba ama na ugboro nke radieshon.
A na-eji ọtụtụ ụzọ iji kwado microstructural, thermal na eletriki homogeneity nke heterostructures: scanning transfer electron microscopy (STEM), photoluminescence spectroscopy (PL), Kelvin probe microscopy (KPM), scanning thermal microscopy (SThM), yana Raman spectroscopy na temometa .
Image Image 1b na-egosi anyị ụdịdị dị iche iche nke Raman nke Gr/MoSe2/MoS2/WSe22 heterostructure na mkpụrụ SiO2/Si n'ebe akara ya na ntụpọ uhie. Ihe nkata a na-egosi mbinye aka nke monolayer ọ bụla n'usoro oyi akwa, yana mbinye aka nke mkpụrụ Si.
Na 1c-1f E gosipụtara onyonyo STEM gbara ọchịchịrị nke Gr/MoSe2/MoS2/WSe22 heterostructure (1c) na Gr/MoS2/WSe22 heterostructures (1d-1f) n'ụzọ dị iche iche lattice. Onyonyo STEM na-egosi oghere vdW dị nso na-enweghị mmetọ ọ bụla, na-enye ohere ka a na-ahụ anya nke ọma n'ogo nke ihe ndị a. A kwadoro ọnụnọ nke njikọ interlayer n'elu nnukwu ebe nyocha site na iji photoluminescence (PL) spectroscopy (1g). A na-ebelata akara ngosi fotoluminescent nke ọkwa onye ọ bụla n'ime heterostructure ma e jiri ya tụnyere mgbama nke monolayer dịpụrụ adịpụ. A na-akọwa nke a site na usoro nnyefe ego interlayer n'ihi mmekọrịta dị nso na interlayer, nke na-esiwanye ike mgbe ọ kwụsịrị.
Foto #2
Iji tụọ okpomọkụ na-erugharị perpendicular na ụgbọ elu atọm nke heterostructure, a na-ahazi ọtụtụ ọkwa n'ụdị ngwaọrụ eletriki anọ. N'elu oyi akwa nke graphene kọntaktị palladium (Pd) electrodes ma ejiri ya dị ka igwe ọkụ maka nha temometa Raman.
Usoro ikpo ọkụ eletrik a na-enye ọnụ ọgụgụ ziri ezi nke ike ntinye. Usoro kpo oku ọzọ nwere ike ime, ngwa anya, ga-esikwu ike imejuputa n'ihi amaghị nke ọnụọgụ absorption nke ọkwa nke onye ọ bụla.
Na 2 na-egosi sekit nha nyocha anọ, na 2b na-egosi n'elu echiche nke Ọdịdị a na-anwale. Nhazi oge 2c na-egosi njirimara mbufe okpomọkụ maka ngwaọrụ atọ, nke nwere naanị graphene na abụọ nwere Gr/WSe22 na Gr/MoSe2/WSe22. Ụdị dị iche iche na-egosipụta omume ambipolar nke graphene, nke jikọtara ya na enweghị ọdịiche nke band.
Achọpụtakwara na njikwa na ikpo ọkụ dị ugbu a na-eme na elu elu (graphene), ebe ọ bụ na eletrik eletrik ya bụ ọtụtụ iwu nke ịdị elu karịa nke MoS2 na WSe22.
Iji gosipụta ịdị n'otu nke ngwaọrụ ndị a nwalere, a na-ewere nha site na iji Kelvin probe microscopy (KPM) na nyocha microscopy thermal (SThM). Na eserese ahụ 2d A na-egosiputa nha KPM na-egosipụta nkesa nwere ike ịdị n'ahịrị. E gosipụtara nsonaazụ nyocha SthM na 2s. N'ebe a, anyị na-ahụ maapụ nke ọwa Gr / MoS2 / WSe22 na-ekpo ọkụ eletrik, yana ọnụnọ nke otu na kpo oku elu.
Usoro nyocha nke akọwara n'elu, karịsịa SthM, kwadoro homogeneity nke ihe owuwu a na-amụ, ya bụ, ịdị n'otu ya, n'ihe gbasara okpomọkụ. Nzọụkwụ ọzọ bụ iji Raman spectroscopy (ya bụ, Raman spectroscopy) nyochaa okpomọkụ nke ọ bụla n'ime ihe ndị mejupụtara ya.
A nwalere ngwaọrụ atọ niile, nke ọ bụla nwere mpaghara ~40 µm2. N'okwu a, ike kpo oku gbanwere site na 9 mW, na ike laser etinyere n'okpuru ~ 5 μW nwere ebe ntụpọ laser nke ~ 0.5 μm2.
Foto #3
Na eserese ahụ 3 mmụba nke okpomọkụ (∆T) nke oyi akwa ọ bụla na mkpụrụ na-ahụ anya ka ike ọkụ na Gr / MoS2 / WSe22 heterostructure na-abawanye.
Mkpọda nke ọrụ linear maka ihe ọ bụla (oyi akwa) na-egosi nkwụsị ọkụ (Rth = ∆T / P) n'etiti onye ọ bụla oyi akwa na ikpo ọkụ. N'iburu nkesa nkesa kpo oku n'elu ebe ahụ, enwere ike nyochaa ihe mgbochi okpomọkụ site na ala ruo n'elu oyi akwa, mgbe a na-edozi ụkpụrụ ha site na mpaghara ọwa (WL).
L na W bụ ogologo ọwa na obosara, nke dị ukwuu karịa ọkpụrụkpụ nke mkpụrụ SiO2 na ogologo ọkụ ọkụ n'akụkụ, nke bụ ~ 0.1 μm.
Yabụ, anyị nwere ike nweta usoro maka nguzogide thermal nke mkpụrụ Si, nke ga-adị ka nke a:
Rth, Si ≈ (WL) 1/2 / (2kSi)
N'ọnọdụ a kSi ≈ 90 W m-1 K-1, nke bụ ihe a na-atụ anya ka ọkụ na-eme ka ọ bụrụ ihe na-eme ka ọ dị elu.
Ihe dị iche n'etiti Rth, WSe2 na Rth, Si bụ nchikota nke thermal eguzogide nke 2 nm oké SiO100 na thermal ókè-eguzogide (TBR) nke WSe2 / SiO2 interface.
N'ijikọta akụkụ niile dị n'elu ọnụ, anyị nwere ike ịmepụta na Rth, MoS2 - Rth, WSe2 = TBRMoS2/Wse2, na Rth, Gr - Rth, MoS2 = TBRGr/MoS2. Ya mere, site na eserese 3 ọ ga-ekwe omume wepụ uru TBR maka nke ọ bụla n'ime WSe2/SiO2, MoS2/WSe2 na Gr/MoS2 interfaces.
Na-esote, ndị ọkà mmụta sayensị tụlere mkpokọta okpomọkụ nke ihe niile heterostructures, tụrụ site na iji Raman spectroscopy na thermal microscopy.3b).
Bilayer na trilayer heterostructures na SiO2 gosipụtara nguzogide okpomọkụ dị irè na nso nke 220 ruo 280 m2 K / GW na ọnụ ụlọ okpomọkụ, nke kwekọrọ na nguzogide thermal nke SiO2 na ọkpụrụkpụ nke 290 ruo 360 nm. N'agbanyeghị eziokwu na ọkpụrụkpụ nke heterostructures a na-amụ adịghị gafere 2 nm (1d-1f), conductivity ha thermal bụ 0.007-0.009 W m-1 K-1 na ụlọ okpomọkụ.
Foto #4
Onyonyo # 4 na-egosi nha nke akụkụ anọ niile yana elele ókèala thermal (TBC) nke oghere ha, nke na-enye anyị ohere inyocha ogo mmetụta nke oyi akwa ọ bụla na nguzogide okpomọkụ a tụrụ na mbụ (TBC = 1 / TBR).
Ndị nyocha ahụ kwuru na nke a bụ nha TBC nke mbụ maka oghere dị nso n'etiti monolayers dị iche iche (2D/2D), kpọmkwem n'etiti WSe2 na SiO2 monolayers.
TBC nke monolayer WSe2/SiO2 interface dị ala karịa nke interface WSe2/SiO2 multilayer, nke na-abụghị ihe ijuanya ebe ọ bụ na monolayer nwere ụdị ụda ụda na-ehulata nke ukwuu dị maka nnyefe. N'ikwu ya n'ụzọ dị mfe, TBC nke interface n'etiti 2D n'ígwé dị ala karịa TBC nke interface n'etiti 2D oyi akwa na 3D SiO2 mkpụrụ (XNUMXD SiOXNUMX).4b).
Maka ịmatakwu nke ọma na nuances nke ọmụmụ ihe, ana m akwado ile anya и nye ya.
Epilogue
Nnyocha a, dị ka ndị ọkà mmụta sayensị n'onwe ha na-ekwu, na-enye anyị ihe ọmụma nwere ike itinye n'ọrụ na mmejuputa atomiki thermal interfaces. Ọrụ a gosipụtara ohere nke ịmepụta metamaterials na-ekpo ọkụ na-ekpo ọkụ nke na-adịghị ahụ n'okike. Tụkwasị na nke ahụ, ọmụmụ ihe ahụ gosikwara na ọ ga-ekwe omume na-ebupụta nha okpomọkụ nke ihe ndị dị otú ahụ, n'agbanyeghị ọnụ ọgụgụ atomic nke n'ígwé.
Heterostructures akọwara n'elu nwere ike ịghọ ihe ndabere maka ultra-light na kọmpat thermal "shield", nke nwere ike, dịka ọmụmaatụ, wepụ okpomọkụ site na ebe ọkụ na ngwá electronic. Tụkwasị na nke a, enwere ike iji nkà na ụzụ a na ndị na-emepụta ọkụ ọkụ ma ọ bụ ngwaọrụ na-achịkwa ọkụ, na-abawanye arụmọrụ ha.
Ọmụmụ ihe a na-akwado ọzọ na sayensị ọgbara ọhụrụ nwere mmasị siri ike n'ụkpụrụ nke "ịrụ ọrụ dị na thimble," nke a na-apụghị ịkpọ echiche nzuzu, nyere obere ihe onwunwe nke mbara ala na ọganihu na-aga n'ihu na-achọ ụdị nkà na ụzụ ọhụrụ.
Daalụ maka nlebara anya gị, na-achọ ịmata ihe ma nwee ọmarịcha izu onye ọ bụla! 🙂
Daalụ maka ịnọnyere anyị. Akụkọ anyị ọ masịrị gị? Chọrọ ịhụ ọdịnaya na-atọ ụtọ karị? Kwado anyị site n'itinye iwu ma ọ bụ ịkwado ndị enyi, Mbelata 30% maka ndị ọrụ Habr na analog pụrụ iche nke sava ọkwa ntinye, nke anyị chepụtara maka gị: (dị na RAID1 na RAID10, ruo 24 cores na ruo 40GB DDR4).
Dell R730xd ugboro abụọ dị ọnụ ala? Naanị ebe a na Netherlands! Dell R420 - 2x E5-2430 2.2Ghz 6C 128GB DDR3 2x960GB SSD 1Gbps 100TB - sitere na $99! Gụkwuo banyere ya
isi: www.habr.com