Ƙarfafa Tattara Hasken Daga Cibiyoyin Launin GaN Ta Amfani da Ruwan Tabarau Mai Kusa da Ma'auni (SIL)

1. Gabatarwa & Bayyani

Wannan rahoton yana nazarin wani muhimmin bincike da ya magance wata matsala ta asali a cikin ilimin haske na quantum na daskararru: rashin ingantaccen cire photon daga semiconductors masu babban ma'auni na refractive. Binciken ya nuna amfani da ruwan tabarau mai kusa da ma'auni (SIL) don haɓaka tattara haske daga cibiyar launi ɗaya a cikin Gallium Nitride (GaN). Babban nasarar ita ce haɓakar ingancin tattara photon sau 4.3 ± 0.1 a zafin daki, tare da ingantaccen ingantaccen ƙudurin hoto na gefe. Wannan aikin ya haɗa fasahar semiconductor na III-nitride mai cikakken ci gaba da kimiyyar bayanai na quantum, yana ba da mafita mai amfani, bayan kera, don haɓaka aikin masu fitar da quantum.

2. Bayanan Baya & Dalili

2.1 Cibiyoyin Launi a matsayin Tushen Hasken Quantum

Cibiyoyin launi su ne lahani na ma'auni na atom a cikin lu'ulu'u waɗanda zasu iya fitar da photon guda ɗaya. Sun haɗa ƙayyadaddun jihohin quantum na atom tare da kwanciyar hankali da haɗakar da mai masaukin daskararru. Dandamali masu nasara sun haɗa da lu'ulu'u (cibiyoyin NV, SiV), silicon carbide, da kuma kwanan nan, hexagonal boron nitride (hBN). Aikinsu, musamman a zafin daki, yana yiwuwa ta hanyar babban bandgap na kayan masaukin, wanda ke hana ionization na zafi na jihohin lantarki na lahani.

2.2 Batun Gallium Nitride (GaN)

GaN ya fice saboda cikakken ci gabansa na masana'antu, wanda LEDs da na'urorin lantarki suka motsa. Wannan cikakken ci gaban yana fassara zuwa manyan kayan aiki masu inganci, ƙarancin farashi, iyawar girma na epitaxial (misali, akan silicon), da ingantattun dabarun sarrafawa. Gano masu fitar da quantum a zafin daki a cikin GaN, kamar yadda aka ruwaito a cikin ayyuka kamar na Nguyen et al. (2019), ya buɗe kofa don amfani da wannan yanayin da ake da shi don ilimin haske na quantum mai ma'auni. Duk da haka, babban ma'auni na refractive na GaN ($n_{GaN} \approx 2.35$ a 815 nm) yana iyakance cire photon sosai saboda cikakken tunani na ciki (TIR).

3. Hanyar Fasaha: Ruwan Tabarau Mai Kusa da Ma'auni (SIL)

3.1 Ka'idar Aiki

Ana sanya SIL mai kusan ma'auni kai tsaye a saman samfurin, tare da sanya mai fitarwa a tsakiyarsa (ma'auni mara lahani). Ruwan tabarau yana ƙara ma'auni na taro (NA) na tsarin tattarawa a ciki na babban ma'auni na kayan. Babban fa'idar ita ce, yana kaucewa mummunan refraction da TIR da ke faruwa a mahadar GaN da iska. Ingantaccen ƙudurin gefe ana bayar da shi ta $λ / (n_{SIL} \cdot NA)$, yana samun fa'ida ta $n_{SIL}$ akan hoto ba tare da SIL ba.

3.2 Zaɓin Kayan: Zirconium Dioxide (ZrO2)

Zaɓin wayo na binciken shine ZrO2 (cubic zirconia) don SIL. Ma'auninsa na refractive ($n_{SIL} \approx 2.13$ a 815 nm) yana "kusa da ma'auni" ga GaN ($n_{GaN} \approx 2.35$). Wannan yana rage asarar tunani na Fresnel a mahadar mai mahimmanci na GaN-SIL. Tsarin reflectance na al'ada shine $R = \left( \frac{n_{GaN} - n_{SIL}}{n_{GaN} + n_{SIL}} \right)^2$. Ga waɗannan ma'auni, $R \approx 0.0025$ ko 0.25%, ma'ana fiye da 99.7% na haske yana wucewa daga GaN zuwa SIL, wani muhimmin abu don ingancin da aka samu.

4. Tsarin Gwaji & Sakamako

4.1 Bayanin Samfurin

Gwajin ya yi amfani da Layer na GaN mai rabin polar da aka girma akan substrate na sapphire. An gano takamaiman cibiyar launi mai haske da ke fitar da haske a kusa da infrared (kusan 815 nm) a zafin daki a matsayin mai fitar da quantum da aka yi niyya.

4.2 Babban Binciken Gwaji

Sakamako na farko shine auna kai tsaye na ƙaruwar adadin photon da aka tattara daga cibiyar launi ɗaya kafin da bayan sanya ZrO2 SIL. An ƙididdige ƙimar haɓaka a matsayin 4.3 ± 0.1. A lokaci guda, hoton confocal ya tabbatar da ingantaccen ingantaccen ƙudurin sararin samaniya.

4.3 Bayanai & Ma'auni na Aiki

Haɓakar Tattara Photon

4.3x

± 0.1

Ma'auni na Refractive (GaN @815nm)

~2.35

Ma'auni na Refractive (ZrO2 SIL @815nm)

~2.13

Reflectance na Mahadar

<0.3%

Bayanin Chati/Zane: Zane na ra'ayi zai nuna tsarin microscopy na confocal. A hagu, ba tare da SIL ba: yawancin photon daga mai fitarwa (digo a cikin GaN) suna fuskantar cikakken tunani na ciki a mahadar GaN da iska, tare da ƙaramin haske kawai yana tserewa. A dama, tare da SIL na ZrO2 mai kusan ma'auni da aka haɗa: mazugi na tserewa ya faɗaɗa sosai a cikin SIL, kuma babban ruwan tabarau na NA yana tattara wannan faɗaɗaɗɗen haske yadda ya kamata. Wani jadawali na biyu zai zana ƙimar adadin photon (y-axis) vs. lokaci ko ƙarfi (x-axis) don alamomi biyu: ƙaramin sigina mai kwanciyar hankali (ba tare da SIL ba) da sigina mai girma sosai, mai kwanciyar hankali (tare da SIL), yana nuna ƙaruwar ~4.3x a sarari.

5. Nazari & Tattaunawa

5.1 Babban Fahimta & Tsarin Hankali

Babban Fahimta: Babban shingen amfani da semiconductors na masana'antu kamar GaN don ilimin haske na quantum ba shine ƙirƙirar mai fitar da quantum ba—shine fitar da photon. Wannan takarda tana ba da ingantacciyar magani, mai ƙarancin rikitarwa. Hankali ba shi da lahani: 1) GaN yana da manyan masu fitarwa amma mummunan cire haske. 2) SILs mafita ce da aka sani a ilimin haske na gargajiya. 3) Ta hanyar daidaita ma'aunin SIL da GaN sosai, sun rage babbar hanyar asara da wasu sukan yi watsi da ita. Sakamakon ba haɓaka kawai ba ne; yana mai canzawa wanda ke sa tsoffin tushen da ba su da haske su zama masu amfani a aikace.

5.2 Ƙarfi & Kurakuran Hanyar

Ƙarfi:

Sauƙi & Sarrafa Bayan: Wannan shine haɓaka "ɗauka da sanya". Kana samun mai fitarwa mai kyau da farko, sannan ka haɓaka shi. Wannan yana guje wa babban haɗarin gazawa da rikitarwa na injiniyan tsarin nanostructures (kamar ginshiƙai ko gratings) a kusa da wurin mai fitarwa da ba a sani ba.
Faɗaɗa & Ƙarfi: Haɓaka yana aiki a faɗin bakan haske, ba kamar tsarin resonant ba. Haka nan yana da kwanciyar hankali na injiniya da zafi.
Amfani da Fasahar Da Ake Da Ita: Yana amfani da ingantattun dabarun microscopy na confocal, ba yana buƙatar kayan aiki na ban mamaki ba.

Kurakurai & Iyakoki:

Ba A Haɗa Shi Ba: Wannan shine giwa a cikin ɗaki. SIL mai girma da ke zaune akan guntu bai dace da haɗakar da'irori na quantum photonic mai ma'auni ba. Kayan aiki ne mai ban sha'awa don bincike na asali da tabbatar da ra'ayi, amma ƙarshen ƙarshe ga samfurin ma'auni na guntu.
Hankalin Daidaitawa: Duk da cewa daidaitawar "gabaɗaya" ta isa, ingantaccen aiki yana buƙatar daidaitaccen sanya mai fitarwa a wurin da ba shi da lahani na SIL, wanda zai iya zama kalubale.
Rashin Cikakken Kayan: Rashin daidaiton ma'auni, ko da yake ƙanƙanta, har yanzu yana haifar da wasu asara. Nemo cikakkiyar daidaiton ma'auni (misali, wani kayan SIL daban ko ƙirar GaN) zai iya tura haɓaka kusa da iyakar ka'idar na ~$n_{SIL}^2$.

5.3 Fahimta Mai Amfani & Tasiri

Ga masu bincike da manajoji na R&D:

Kayan Aiki Nan da Nan don Siffantawa: Kowane dakin aiki akan GaN ko makamantansu masu fitar da quantum masu babban ma'auni ya kamata ya sami saitin SILs masu daidaitaccen ma'auni. Ita ce hanya mafi sauri don tantance kaddarorin na asali na quantum optical na lahani ta hanyar rage asarar tattarawa.
Dabarar Gada: Yi amfani da na'urori masu haɓaka SIL don ƙirƙira aikin quantum cikin sauri (misali, firikwensin, sadarwa) yayin da ƙungiyoyi masu layi daya ke aiki akan mafita masu haɗawa (taper na baya-baya, masu haɗaɗɗen saman meta).
Jagorar Binciken Kayan: Nasarar ta jaddada buƙatar mahimmanci don ba da rahoton ba kawai gano sabbin masu fitarwa ba, amma aikin su bayansa na injiniyan cirewa na asali. Mai fitarwa "mai duhu" tare da SIL na iya zama mai haske.
Damar Mai Sayarwa: Akwai kasuwa don ingantattun SILs masu daidaitaccen ma'auni (ZrO2, GaN, SiC) waɗanda aka keɓance don binciken quantum. Tsaftacewa da daidaitawa da rufi don hana tunani a saman waje suna ƙara ƙima.

Wannan aikin ba kawai yana ba da rahoton lamba ba; yana ba da hanyar aiki don rage haɗari da haɓaka haɓakar kayan aikin quantum bisa manyan semiconductors.

6. Cikakkun Bayanan Fasaha & Tsarin Lissafi

Haɓaka yana da alaƙa da ƙaruwar ingantaccen ma'auni na tattarawa. Matsakaicin rabin kusurwar hasken da aka tattara a cikin semiconductor shine $θ_c = \sin^{-1}(NA / n_{SIL})$. Ba tare da SIL ba, matsakaicin kusurwa a cikin GaN yana iyakance ta hanyar kusurwar mahimmanci don TIR a mahadar GaN da iska: $θ_{c, GaN-air} = \sin^{-1}(1/n_{GaN})$. SIL yana maye gurbin iska da babban ma'auni na matsakaici, yana ba da damar tattara manyan kusurwoyi $θ_c$. Ana iya kiyasin ƙarfin haɓakar ƙarfin da aka tattara don mai fitar da dipole da aka daidaita daidai da mahadar ta hanyar kimanta yawan radiyon sa a cikin kusurwar daskararru da aka tattara. Don hanyar da ba ta da resonant kamar SIL, ƙimar haɓaka $η$ yana daidai da ƙaruwar kusurwar daskararru: $η \propto \frac{1 - \cos(θ_{c, with\ SIL})}{1 - \cos(θ_{c, without\ SIL})}$. Tare da babban manufa na NA da kusancin ma'auni, wannan yana haifar da haɓakar sau da yawa da aka gani.

7. Tsarin Nazari: Misali Mai Amfani

Harka: Kimanta Sabon Mai Fitar da Quantum a SiC. Ƙungiyar bincike ta gano sabon lahani mai fitar da photon guda ɗaya a cikin 4H-SiC ($n \approx 2.6$ a 1100 nm).

Ma'auni na Asali: Yi daidaitaccen taswirar photoluminescence na confocal don gano mai fitarwa guda ɗaya. Yi rikodin lankwasa saturates da ƙimar adadin photon a ƙarƙashin ƙayyadaddun yanayi (misali, 1 mW excitation, takamaiman manufa NA). Wannan shine ma'aunin "ba a haɓaka ba".
Aikace-aikacen SIL: Zaɓi kayan SIL tare da ma'auni na refractive kusa da 2.6. Titanium dioxide (TiO2, rutile, $n \approx 2.5-2.6$) ko kuma hemisphere na SiC da aka girma musamman na iya zama 'yan takara. Saka shi a hankali akan mai fitar da aka gano.
Ma'auni Mai Haɓaka: Maimaita ma'aunin lankwasa saturates. Tsarin nazari ya haɗa da lissafin ƙimar haɓaka: $\text{EF} = \frac{\text{Count Rate}_{\text{with SIL}}}{\text{Count Rate}_{\text{without SIL}}}$.
Fassara: Idan EF ya kai ~6-7, yana daidaita da tsammanin daga ƙaruwar kusurwar daskararru. Idan EF ya yi ƙasa sosai, yana haifar da bincike cikin: ingancin kayan SIL/rashin daidaiton ma'auni, sanya mai fitarwa, ko ayyukan da ba na radiyo ba a cikin mai fitarwa da kansa ya zama sabon abin iyakancewa. Wannan tsarin yana raba iyakokin cirewa da iyakokin na asali na mai fitarwa.

Wannan ingantacciyar hanyar, wacce binciken GaN ya yi wahayi zuwa gare ta, tana ba da ma'auni mai ma'ana, mai ƙima don tantance ainihin yuwuwar kowane sabon mai fitar da quantum na daskararru.

8. Aikace-aikace na Gaba & Hanyoyin Bincike

Tsarin Haɗakar da Hybrid: Duk da yake SILs masu zaman kansu ba a haɗa su ba, ra'ayin zai iya ƙarfafa micro-SILs akan guntu ko filaye masu ruwan tabarau da aka ƙera kai tsaye ko aka haɗa su akan da'irori na haɗakar da hoto (PICs) don haɗa haske daga masu fitarwa zuwa masu jagorar haske.
Samfuran Firikwensin Quantum: Masu fitar da GaN masu haske, masu haɓaka SIL, sun dace don haɓaka ƙananan firikwensin quantum masu ɗaukar hoto, masu aiki a zafin daki (magnetometers, thermometers) don amfani da dakin gwaje-gwaje, inda ɗaukar hoto ya fi mahimmanci fiye da cikakken haɗakar guntu.
Dandalin Gano Kayan: Wannan dabarar za ta zama mahimmanci don tantance sabbin kayan masu faɗin bandgap (misali, oxides, sauran III-nitrides) don lahani na quantum, yayin da take bayyana yuwuwar aikin mai fitarwa cikin sauri.
Ƙirar SIL Mai Ci Gaba: Aikin nan gaba na iya bincika SILs na supersphere don mafi girman NA, ko SILs da aka yi daga kayan da ba na layi ba don haɗa haɓakar tattarawa tare da canza wavelength a cikin kashi ɗaya.

Zuwa Haɗakarwa: Jagorar ƙarshe ita ce fassara ka'idar zahiri na SIL zuwa tsarin nanophotonic—irinsu gratings na bullseye ko masu nuna alama—waɗanda aka ƙera gaba ɗaya a kusa da cibiyar launi, suna ba da fa'idodin cirewa iri ɗaya a cikin tsari mai ma'auni, mai ma'auni.

9. Nassoshi

Aharonovich, I., Englund, D., & Toth, M. (2016). Solid-state single-photon emitters. Nature Photonics, 10(10), 631–641.

Nguyen, M., et al. (2019). Photophysics of point defects in GaN. Physical Review B, 100(16), 165301. (An ambaci a matsayin aikin tushe akan cibiyoyin launin GaN).

Manson, N. B., et al. (2006). NV centers in diamond: Properties and applications. Journal of Physics: Condensed Matter, 18(21), S87.

Castelletto, S., & Boretti, A. (2020). Silicon carbide color centers for quantum applications. Journal of Physics: Photonics, 2(2), 022001.

Bishop, S. G., et al. (2020). Enhanced light collection from a gallium nitride color center using a near index-matched solid immersion lens. Applied Physics Letters, 117, 084001. (Babban takarda da aka bincika).

Lodahl, P., et al. (2015). Chiral quantum optics. Nature, 541(7638), 473–480. (Don mahallin injiniyan mahadar mai fitarwa-photon).

Jami'ar Cardiff, Makarantar Physics da Astronomy. (n.d.). Ƙungiyar Hasken Quantum & Kwayoyin Halitta. An samo daga gidan yanar gizon jami'a. (A matsayin misali na ƙungiyar bincike mai aiki a wannan yanki).