Kev sib txuas lus optical band, ultra-thin optical resonator

Kev sib txuas lus optical band, ultra-thin optical resonator
Cov khoom siv kho qhov muag tuaj yeem nrhiav qhov chaw tshwj xeeb ntawm cov nthwv dej ntawm lub teeb hauv qhov chaw tsawg, thiab muaj cov ntawv thov tseem ceeb hauv kev sib cuam tshuam ntawm lub teeb thiab cov khoom,kev sib txuas lus pom kev, kev pom kev zoo, thiab kev sib koom ua ke ntawm lub teeb. Qhov loj ntawm lub resonator feem ntau nyob ntawm cov yam ntxwv ntawm cov khoom siv thiab qhov wavelength ua haujlwm, piv txwv li, silicon resonators ua haujlwm hauv qhov ze infrared band feem ntau xav tau cov qauv kho qhov muag ntawm ntau pua nanometers thiab siab dua. Nyob rau hauv xyoo tas los no, ultra-thin planar optical resonators tau nyiam ntau qhov kev saib xyuas vim lawv cov kev siv tau hauv cov xim qauv, holographic imaging, lub teeb teb tswj thiab optoelectronic khoom siv. Yuav ua li cas kom txo qhov tuab ntawm planar resonators yog ib qho ntawm cov teeb meem nyuaj uas cov kws tshawb fawb ntsib.
Txawv ntawm cov ntaub ntawv semiconductor ib txwm muaj, 3D topological insulators (xws li bismuth telluride, antimony telluride, bismuth selenide, thiab lwm yam) yog cov ntaub ntawv tshiab nrog cov hlau tiv thaiv topologically thiab cov xeev insulator. Lub xeev nto yog tiv thaiv los ntawm symmetry ntawm lub sijhawm inversion, thiab nws cov electrons tsis tawg los ntawm cov khoom tsis muaj hlau nplaum, uas muaj cov kev cia siab tseem ceeb hauv kev suav quantum qis zog thiab cov khoom siv spintronic. Tib lub sijhawm, cov ntaub ntawv topological insulator kuj qhia cov khoom siv optical zoo heev, xws li cov ntsuas refractive siab, cov nonlinear lojkho qhov muagcoefficient, dav spectrum ua haujlwm, tunability, yooj yim kev koom ua ke, thiab lwm yam, uas muab lub platform tshiab rau kev paub txog kev tswj lub teeb thiabcov khoom siv hluav taws xob optoelectronic.
Ib pab pawg tshawb fawb hauv Suav teb tau tawm tswv yim ib txoj kev rau kev tsim cov khoom siv kho qhov muag ultra-thin los ntawm kev siv thaj chaw loj loj bismuth telluride topological insulator nanofilms. Lub qhov muag pom tau tias muaj cov yam ntxwv ntawm kev nqus resonance hauv qhov ze infrared band. Bismuth telluride muaj cov refractive index siab heev ntawm ntau dua 6 hauv cov kab sib txuas lus kho qhov muag (siab dua li cov refractive index ntawm cov ntaub ntawv refractive index siab ib txwm muaj xws li silicon thiab germanium), yog li ntawd qhov tuab ntawm qhov muag tuaj yeem ncav cuag ib-nees nkaum ntawm qhov resonance wavelength. Tib lub sijhawm, lub resonator kho qhov muag tau tso rau ntawm ib-dimensional photonic crystal, thiab qhov tshiab electromagnetically induced transparency effect tau pom nyob rau hauv cov kab sib txuas lus kho qhov muag, uas yog vim muaj kev sib txuas ntawm lub resonator nrog Tamm plasmon thiab nws qhov kev cuam tshuam puas tsuaj. Cov lus teb spectral ntawm cov nyhuv no nyob ntawm qhov tuab ntawm lub resonator kho qhov muag thiab muaj zog rau qhov kev hloov pauv ntawm ambient refractive index. Cov haujlwm no qhib txoj hauv kev tshiab rau kev paub txog qhov muag ultrathin, cov khoom siv insulator topological spectrum kev tswj hwm thiab cov khoom siv optoelectronic.
Raws li pom hauv daim duab 1a thiab 1b, lub tshuab hluav taws xob kho qhov muag feem ntau yog tsim los ntawm cov bismuth telluride topological insulator thiab cov nanofilms nyiaj. Cov bismuth telluride nanofilms uas npaj los ntawm magnetron sputtering muaj thaj chaw loj thiab tiaj tus zoo. Thaum lub thickness ntawm bismuth telluride thiab cov zaj duab xis nyiaj yog 42 nm thiab 30 nm, feem, lub qhov muag pom kev zoo heev hauv 1100 ~ 1800 nm (Daim Duab 1c). Thaum cov kws tshawb fawb koom ua ke lub qhov muag no rau ntawm lub photonic siv lead ua los ntawm cov pawg sib txawv ntawm Ta2O5 (182 nm) thiab SiO2 (260 nm) txheej (Daim Duab 1e), ib lub hav dej nqus tau sib txawv (Daim Duab 1f) tshwm sim ze ntawm lub ncov nqus resonant thawj (~ 1550 nm), uas zoo ib yam li cov nyhuv transparency electromagnetically tsim los ntawm cov kab ke atomic.

Cov khoom siv bismuth telluride tau piav qhia los ntawm kev siv lub tshuab kuaj hluav taws xob thiab ellipsometry. Daim duab 2a-2c qhia txog cov duab micrographs ntawm kev siv hluav taws xob (cov duab zoo siab) thiab cov qauv diffraction hluav taws xob xaiv ntawm bismuth telluride nanofilms. Nws tuaj yeem pom los ntawm daim duab tias cov nanofilms bismuth telluride uas tau npaj tseg yog cov khoom siv polycrystalline, thiab qhov kev loj hlob tseem ceeb yog (015) lub dav hlau siv lead ua. Daim duab 2d-2f qhia txog qhov ntsuas refractive ntawm bismuth telluride ntsuas los ntawm ellipsometer thiab lub xeev nto thiab lub xeev refractive index. Cov txiaj ntsig qhia tau tias qhov coefficient extinction ntawm lub xeev nto yog ntau dua li qhov ntsuas refractive hauv qhov ntau ntawm 230 ~ 1930 nm, qhia txog cov yam ntxwv zoo li hlau. Qhov ntsuas refractive ntawm lub cev yog ntau dua 6 thaum lub wavelength ntau dua 1385 nm, uas siab dua li ntawm silicon, germanium thiab lwm yam khoom siv ntsuas refractive siab hauv cov kab no, uas tso lub hauv paus rau kev npaj cov resonators optical ultra-thin. Cov kws tshawb fawb taw qhia tias qhov no yog thawj zaug tau tshaj tawm txog kev paub txog lub topological insulator planar optical cavity nrog lub thickness ntawm tsuas yog kaum tawm nanometers hauv optical communication band. Tom qab ntawd, lub spectrum absorption thiab resonance wavelength ntawm ultra-thin optical cavity tau ntsuas nrog lub thickness ntawm bismuth telluride. Thaum kawg, qhov cuam tshuam ntawm cov nyiaj zaj duab xis tuab ntawm electromagnetically induced transparency spectra hauv bismuth telluride nanocavity / photonic crystal structures raug tshawb nrhiav.

Los ntawm kev npaj cov yeeb yaj kiab nyias nyias ntawm bismuth telluride topological insulators, thiab siv qhov ntsuas refractive siab heev ntawm Bismuth telluride cov ntaub ntawv hauv ze infrared band, lub planar optical cavity nrog tuab ntawm kaum tawm nanometers tau txais. Lub ultra-thin optical cavity tuaj yeem paub txog kev nqus lub teeb resonant zoo hauv ze infrared band, thiab muaj txiaj ntsig tseem ceeb rau kev tsim cov khoom siv optoelectronic hauv optical communication band. Lub thickness ntawm bismuth telluride optical cavity yog linear rau resonant wavelength, thiab yog me dua li ntawm silicon thiab germanium optical cavity zoo sib xws. Tib lub sijhawm, bismuth telluride optical cavity yog koom ua ke nrog photonic crystal kom ua tiav qhov cuam tshuam optical anomalous zoo ib yam li electromagnetically induced transparency ntawm atomic system, uas muab ib txoj hauv kev tshiab rau kev tswj spectrum ntawm microstructure. Txoj kev tshawb fawb no ua lub luag haujlwm tshwj xeeb hauv kev txhawb nqa kev tshawb fawb ntawm cov ntaub ntawv topological insulator hauv kev tswj lub teeb thiab cov khoom siv optical.