研究内容 Research

従来のエレクトロニクスでは、チャージ(電荷)の制御により情報処理が行われてきました。これに対してスピントロニクスは、チャージだけでなくスピン(磁性)を制御することにより情報処理を行っていくものです。半導体を用いる代表的なスピントロニクス素子は、InAs・InGaAs・InSb・InGaSb など大きなスピン軌道結合を有する半導体ナローチャネルと強磁性体金属電極からなるスピン電界効果トランジスタです。本研究室では、このスピン電界効果トランジスタに着目し、その構成要素となる半導体ナノワイヤ構造および半導体-強磁性体複合構造に関する実験的研究を行っています。

The information technology supported by the electronics is based on controlling electric charge. The spintronics is controlling not only electric charge but also spin direction for the future information technology. The most typical spintronic device using a semiconductor (SC) is spin field-effect transistor (spin-FET), which consists of a SC narrow channel having large spin-orbit coupling (InAs, InGaAs, InSb, InGaSb etc.) and ferromagnetic metal (FM) electrodes. According to the background, we investigate SC nanowire structures and SC-FM hybrid structures for spintronic applications.

ナノ構造成長 Nanostructure growth

分子線エピタキシー(MBE)装置や電気化学堆積(ECD)装置を使って、マイクロメートル(μm)からナノメートル(nm)のサイズで長さ・幅・厚さが制御された、半導体ナノワイヤ構造や半導体-強磁性体複合構造を成長しています。
We grow semiconductor nanowire structures and semiconductor-ferromagnetic metal hybrid structures using molecular beam epitaxy (MBE) and electrochemical deposition (ECD). 

ナノデバイス作製 Nanodevice fabrication

電子線リソグラフィー(EBL)装置や電界電離型ガスイオン源集束イオンビーム(GFIS-FIB)装置を使って、成長した試料をマイクロメートル(μm)からナノメートル(nm)のサイズの微細加工することでナノデバイスを作製しています。
We fabricate various nanodevices from the grown samples using electron beam lithography (EBL) and gas field ion source focused ion beam (GFIS-FIB).

ナノデバイス測定 Nanodevice characterization

超伝導マグネットやロックインアンプを使って、極低温(~1.5K)・強磁場(~8T)で作製したナノデバイスを電気的に測定しています。そして、測定結果を解析し、その中での電子やスピンの振舞について知見を得ています。
We electrically measure the fabricated nanodevices under low temperature (~1.5K) and high magnetic field (~8T) using a superconducting magnet and lock-in amplifier. We analyze the measurement results and find out electron and spin behaviors in the nanodevices.

実験設備 Facilities

クラス1000クリーンルーム Class 1000 Clean Room

クラス10クリーンルーム Class 10 Clean Room

分子線エピタキシー装置 Molecular Beam Epitaxy

電気化学堆積装置 Electro-Chemical Deposition

マスクレスアライナー装置 Mask-Less Aligner

電子線リソグラフィー装置 Electron Beam Lithography

電界電離型ガスイオン源集束イオンビーム装置 Gas Field Ion Source Focused Ion Beam

超伝導量子干渉型磁束計 Superconducting QUantum Interference Device Magnetometer

ホール効果測定装置 Hall Effect Measurement System

超伝導マグネット Super-Conducting Magnet

ロックインアンプ Lock-In Amplifiers

走査型電子顕微鏡 Scanning Electron Microscope

論文 Papers

  1. C. Helman , A. Camjayi, E. Islam, M. Akabori, L. Thevenard ,C. Gourdon, and M. Tortarolo
    "Anomalous Hall effect in MnAs: Intrinsic contribution due to Berry curvature"
    Phys. Rev. B, Vol. 103, pp. 134408-1-6 (2021).
    [アルゼンチンCAC、フランスCNRSとの共同研究]

  2. D. Q. Tran, Md. E. Islam, K. Higashimine, M. Akabori
    "Self-catalyst growth and characterization of wurtzite GaAs/InAs core/shell nanowires"
    J. Crystal Growth, Vol. 564, pp. 126126-1-7 (2021).
    [修了生のTranさんとIslamさんの研究成果]

  3. M. Mori, M. Akabori, M. Tomitori, T. Masuda
    "Non-thermal liquid-to-solid Si conversion induced by electron beam irradiation"
    Jpn. J. Appl. Phys.,  Vol. 60, pp. SBBM03-1-5 (2021). 
    [増田研、富取研との共同研究]

  4. T. Iwasaki, O. G. Agbonlahor, M. Muruganathan, M. Akabori, Y. Morita, S. Moriyama, S. Ogawa, Y. Wakayama, H. Mizuta, S. Nakaharai
    “Room-temperature negative magnetoresistance of helium ion-irradiated defective graphene in the strong Anderson localization regime”
    Carbon, Vol. 175, pp. 87-92 (2021)
    [NIMS、群馬大、AIST、水田研との共同研究]

  5. M. N. Dang, H. T. Nguyen, T. V. Nguyen, T. V. Thu, H. Le, M. Akabori, N. Ito, H. Y. Nguyen, L. T. Le, H. T. Nguyen, T. V. Nguyen, H. N. Phan
    “One-pot synthesis of manganese oxide/graphene composites via plasma-enhanced electrochemical exfoliation process for supercapacitors”
    Nanotechnology, Vol. 31, pp. 345401-1-10 (2020).
    [ベトナム日越大、ベトナムVASTとの共同研究]

  6. H. Oomae, K. Sato, M. Shinoda, M. I. Faris bin Ishak, H. Toyota, M. Akabori, H. Kizaki, S. Nakamura, J. T. Asubar, N. Uchitomi
    “Epitaxial growth and characterization of Cr-doped ZnSnAs2 thin films on InP substrates”
    Jpn. J. Appl. Phys., Vol. 59, pp. 030601-1-6 (2020).
    [長岡技科大、大阪大との共同研究]

  7. Md. E. Islam, K. Hayashida, M. Akabori
    “Spin injection and detection in MnAs/GaAs/InAs hybrid system on GaAs(111)B through lateral non-local spin valve measurement at varied temperature”
    AIP Advances, Vol. 9, pp. 115215-1-6 (2019).
    [修了生のIslamさんと林田さんの研究成果]

  8. R. Negishi, C. Wei, Y. Yao, Y. Ogawa, M. Akabori, Y. Kanai, K. Matsumoto, Y. Taniyasu, Y. Kobayashi
    “Turbostratic Stacking Effect in Multilayer Graphene on the Electrical Transport Properties”
    Phys. Status Solidi B, Vol. 256, pp. 1900437-1-5 (2019).
    [大阪大、NTT物性基礎研との共同研究]

  9. T. Chen, M. Akabori, Y. Oshima
    “Strain mapping at the interface of InP/InxGa1-xAs/InP as measured by the scanning transmission electron microscope-moiré fringe method”
    Appl. Phys. Express, Vol. 12, pp. 105504-1-4 (2019).
    [大島研との共同研究]

  10. H. Nguyen, T. Nguyen, L. Nguyen, H. Nguyen, L. Phan, V. Nguyen, L. T. T. Nguyen, H. Hoang, H. Tran, P. Mai, Md. Zaidan, H. Murata, M. Akabori
    “Direct (Hetero)Arylation Polymerization for The Synthesis of D-A Conjugated Polymers Based on N-Benzoyldithieno[3,2-b:2’,3’-d]pyrrole and Diketopyrrolopyrrole Toward Organic Photovoltaic Cell Application”
    Polymer International Vol. 68, pp. 1776–1786 (2019). 
    [ベトナムホーチミン工科大、村田研との共同研究]

  11. C. Wei, R. Negishi, Y. Ogawa, M. Akabori, Y. Taniyasu, Y. Kobayashi
    “Turbostratic multilayer graphene synthesis on CVD graphene template toward improving electrical performance”
    Jpn. J. Appl. Phys., Vol. 58, pp. SIIB04-1-5 (2019).
    [大阪大、NTT物性基礎研との共同研究]

  12. S. Yamada, A. Fujimoto, S. Hidaka, M. Akabori, Y. Imanaka, K. Takehana
    “Fractional quantum Hall effects in In0.75Ga0.25As bilayer electron systems observed as “Finger print””
    Scientific Reports, Vol. 9, pp. 7446-1-10 (2019). 
    [大阪工大、NIMSとの共同研究]

  13. R. C. Shende, M. Muruganathan, H. Mizuta, M. Akabori, R. Sundara
    “Chemical Simultaneous Synthesis Strategy of Two Nitrogen-Rich Carbon Nanomaterials for All-Solid-State Symmetric Supercapacitor”
    ACS OMEGA, Vol. 3, pp. 17276-17286 (2018). 
    [インドIITM、水田研との共同研究]

  14. T. X. Pham, M. Miyata, N. V. Huynh, L. T. Pham, T. T. Nguyen, M. Muruganathan, T. T. Phan, M. Akabori, C. H. Dam, H. Mizuta, Y. Takamura, M. Koyano
    “Thermoelectric Properties and Carrier Localization in Ultrathin Layer of Nb-Doped MoS2”
    Phys. Status Solidi B, Vol. 255, pp. 1800125-1-8 (2018). 
    [小矢野研、高村研、水田研、ダム研との共同研究]

  15. M. E. Schmidt, M. Akabori, H. Mizuta
    “Ion Beam Applications: Chapter 6: Nitrogen Ion Microscopy”
    IntechOpen (2018).
    [水田研との共同研究]

  16. Md. E. Islam, M. Akabori
    “In-plane isotropic magnetic and electrical properties of MnAs/InAs/GaAs(111)B hybrid structure”
    Physica B, Vol. 532, pp. 95-98 (2018). 
    [Islamさんの研究成果]

  17. D. Q. Tran, H. T. Pham, K. Higashimine, Y. Oshima, M. Akabori
    “Three-dimensional lattice rotation in GaAs nanowire growth on hydrogen-silsesquioxane covered GaAs (001) using molecular beam epitaxy”
    Physica E, Vol. 99, pp. 58-62 (2018).
    [Tranさんの研究成果]

  18. H. T. Pham, T. D. Nguyen, Md. E. Islam, D. Q. Tran, M. Akabori
    “Enhanced ferromagnetism of ZnO@Co/Ni hybrid core@shell nanowires grown by electrochemical deposition method”
    RSC Advances, Vol. 8, pp. 632-639 (2018).
    [修了生のPhamさんの研究成果]

  19. H. T. Pham, T. D. Nguyen, D. Q. Tran, M. Akabori
    “Structural, optical and electrical properties of well-ordered ZnO nanowires grown on (111) oriented Si, GaAs and InP substrates by electrochemical deposition method"
    Materials Research Express, Vol. 4, pp. 055002-1-10 (2017). 
    [Phamさんの研究成果]

  20. M. E. Schmidt, A. Yasaka, M. Akabori, H. Mizuta
    “Nitrogen GFIS-FIB secondary electron imaging: A first look”
    Microscopy and Microanalysis, Vol. 23, pp. 758-768 (2017).
    [水田研、日立ハイテクサイエンスとの共同研究]

  21. M. E. Schmidt, X. Zhang, Y. Oshima, L. T. Anh, A. Yasaka, T. Kanzaki, M. Muruganathan, M. Akabori, T. Shimoda, H. Mizuta
    "Interaction study of nitrogen ion beam with silicon"
    J. Vac. Sci. Tech. B, Vol. 35, pp. 03D101-1-7 (2017).
    [水田研、大島研、下田研、日立ハイテクサイエンスとの共同研究]

  22. Md. E. Islam, M. Akabori
    “Growth and magnetic properties of MnAs/InAs hybrid structure on GaAs(111)B”
    J. Crystal Growth, Vol. 463, pp. 86-89 (2017).
    [Islamさんの研究成果]

  23. T. Ohori, M. Akabori, S. Hidaka, S. Yamada
    “Characterization of spin-orbit coupling in gated wire structures using Al2O3/In0.75Ga0.25As/In0.75Al0.25As inverted heterojunctions”
    J. Appl. Phys. Vol. 120, pp. 142123-1-4 (2016).
    [修了生の大堀さんの研究成果]

  24. R. Negishi, M. Akabori, T. Ito, Y. Watanabe, Y. Kobayashi
    “Band-like transport in highly crystalline graphene films from defective graphene oxides”
    Scientific Reports, Vol. 6, pp. 28936-1-10 (2016). 
    [大阪大学、名古屋大学との共同研究]

  25. T. Iwasaki, J. Sun, N. Kanetake, T. Chikuba, M. Akabori, M. Muruganathan, H. Mizuta
    “Hydrogen intercalation: An approach to eliminate silicon dioxide substrate doping to graphene”
    Appl. Phys. Express, Vol. 8, pp. 015101-1-4 (2015). 
    [水田研との共同研究]

  26. M. Akabori, S. Hidaka, S. Yamada, T. Kozakai, O. Matsuda, A. Yasaka
    “High-In-content InGaAs quantum point contacts fabricated using focused ion beam system equipped with N2 gas field ion source”
    Jpn. J. Appl. Phys., Vol. 53, pp. 118002-1-3 (2014). 
    [赤堀研究室発足後初の論文]

    <以下、研究室発足前の論文>
  27. M. Akabori, S. Hidaka, H. Iwase, S. Yamada, U. Ekenberg
    “Realization of In0.75Ga0.25As two-dimensional electron gas bilayer system for spintronics devices based on Rashba spin-orbit interaction”
    J. Appl. Phys., Vol. 112, pp. 113711-1-6 (2012). 

  28. S. Hidaka, M. Akabori, S. Yamada
    “High-efficient long spin coherence electrical spin injection in CoFe/InGaAs two-dimensional electron gas lateral spin-valve devices”
    Appl. Phys. Express, Vol. 5, pp. 113001-1-3 (2012)

  29. C. T. Nguyen, H.-A. Shih, M. Akabori, T. Suzuki
    “Electron distribution and scattering in InAs films on low-k flexible substrates”
    Appl. Phys. Lett., Vol. 100, pp. 232103-1-4 (2012)

  30. M. Akabori, T. Murakami, S. Yamada
    “Selective area molecular beam epitaxy of InAs on GaAs (110) masked substrates for direct fabrication of planar nanowire field-effect transistors”
    J. Crystal Growth, Vol. 345, pp. 22-26 (2012)

  31. H.-A. Shih, M. Kudo, M. Akabori, T. Suzuki
    “Application of sputtering-deposited AlN films to gate dielectric for AlGaN/GaN metal-insulator-semiconductor heterojunction field-effect transistor”
    Jpn. J. Appl. Phys., Vol. 51, pp. 02BF01-1-4 (2012)

  32. M. Kudo, H.-A. Shih, M. Akabori, T. Suzuki
    “Fabrication and analysis of AlN/GaAs(001) and AlN/Ge/GaAs(001) metal-insulator-semiconductor structures”
    Jpn. J. Appl. Phys., Vol. 51, pp. 02BF07-1-5 (2012)

  33. S. Estévez Hernández, M. Akabori, K. Sladek, Ch. Volk, S. Alagha, H. Hardtdegen, M. G. Pala, N. Demarina, D. Grützmacher, Th. Schäpers
    “Spin-orbit coupling and phase coherence in InAs nanowires”
    Phys. Rev. B, Vol. 82, pp. 235303-1-7 (2010)

  34. H. Takita, N. Hashimoto, C. T. Nguyen, M. Kudo, M. Akabori, T. Suzuki
    “Electron transport properties of InAs ultra-thin films obtained by epitaxial lift-off and van der Waals bonding on flexible substrates”
    Appl. Phys. Lett., Vol. 97, pp. 012102-1-3 (2010).
     
  35. Ch. Volk, J. Schubert, M. Akabori, K. Sladek, H. Hardtdegen, Th. Schäpers
    “LaLuO3 as a high-k gate dielectric for InAs nanowire structures”
    Semicond. Sci. Tech., Vol. 25, pp. 085001-1-4 (2010).

  36. Ch. Volk, J. Schubert, K. Weis, S. Estévez Hernández, M. Akabori, K. Sladek, H. Hardtdegen, Th. Schäpers
    “Improved gate-control in InAs nanowire structures by the use of GdScO3 as a gate dielectric”
    Appl. Phys. A, Vol. 100, pp. 305-308 (2010).

  37. M. Akabori, T. Q. Trinh, M. Kudo, Th. Schäpers, H. Hardtdegen, T. Suzuki
    "Strain-enhanced electron mobility anisotropy in InxGa1−xAs/InP two-dimensional electron gases"
    Physica E, Vol. 42, pp. 1130-1133 (2010)

  38. K. Sladek, V. Klinger, J. Wensorra, M. Akabori, H. Hardtdegen, D. Grützmacher
    "MOVPE of n-doped GaAs and modulation doped GaAs/AlGaAs nanowires"
    J. Crystal Growth, Vol. 312, pp. 635-640 (2010)

  39. M. Akabori, K. Sladek, H. Hardtdegen, Th. Schäpers, D. Grützmacher
    “Influence of growth temperature on the selective area MOVPE of InAs nanowires on GaAs (111) B using N2 carrier gas”
    J. Crystal Growth, Vol. 311, pp. 3813-3816 (2009)

  40. Th. Schäpers, V. A. Guzenko, A. Bringer, M. Akabori, M. Hagedorn, H. Hardtdegen
    “Spin-orbit coupling in GaxIn1-xAs/InP 2-dimensional electron gases and quantum wire structures”
    Semicond. Sci. Tech., Vol. 24, pp. 064001-1-11 (2009).

  41. M. Akabori, V. A. Guzenko, Th. Schäpers, H. Hardtdegen
    “InxGa1-xAs/InP selective area MOVPE for non-magnetic semiconductor spintronics”
    J. Crystal Growth, Vol. 310, pp. 4821-4825 (2008).

  42. Y. Jeong, M. Shindo, H. Takita, M. Akabori, T. Suzuki
    “Structural, optical, and electrical characterizations of epitaxial lifted-off InGaAs/InAlAs metamorphic heterostructures bonded on AlN ceramic substrates”
    Phys. Stat. Sol. C, Vol. 5, pp. 2787–2790 (2008).
     
  43. H. Choi, T. Kakegawa, M. Akabori, T. Suzuki, S. Yamada
    “Spin–orbit interactions in high In-content InGaAs/InAlAs inverted heterojunctions for Rashba spintronic devices”
    Physica E, Vol. 40, pp. 2823-2828 (2008)

  44. M. Akabori, V. A. Guzenko, T. Sato, Th. Schäpers, T. Suzuki, S. Yamada
    “Spin-splitting analysis of a two-dimensional electron gas in almost strain-free In0.89Ga0.11Sb/ In0.88Al0.12Sb by magneto-resistance measurements”
    Phys. Rev. B, Vol. 77, pp. 205320-1-6 (2008)

  45. H. Iwase, H. Choi, M. Akabori, T. Suzuki, S. Yamada, D. Yamamoto, T. Ando
    “Fabrication of 3D micro-cantilevers based on MBE grown strained semiconductor layers”
    Physica E, Vol. 40, pp. 2210-2213 (2008)

  46. H. Choi, A. Nogami, T. Kakegawa, M. Akabori, S. Yamada
    “Spin injection in FM/2DEG/FM structures in high-quality In0.75Ga0.25As/In0.75Al0.25As inverted HEMTs”
    Physica E, Vol. 40, pp. 1772-1774 (2008).
     
  47. Y. Jeong, M. Shindo, M. Akabori, T. Suzuki
    “Epitaxial Lift-Off of InGaAs/InAlAs Metamorphic High Electron Mobility Heterostructures and Their van der Waals Bonding on AlN Ceramic Substrates”
    Appl. Phys. Express, Vol. 1, pp. 021201 (2008).

  48. V. A. Guzenko, M. Akabori, Th. Schäpers, S. Cabanas, T. Sato, T. Suzuki, S. Yamada
    “Weak antilocalization measurements on a 2-dimensional electron gas in an InGaSb/InAlSb heterostructure”
    Phys. Stat. Sol. C, Vol. 3, pp. 4227-4230 (2007). 

  49. M. Akabori, T. Sunouchi, T. Kakegawa, T. Sato, T. Suzuki, S. Yamada
    “Spin splitting in InGaSb/InAlSb 2DEG having high indium content”
    Physica E, Vol. 34, pp. 413-416 (2006).

  50. T. Kita, T. Kakegawa, M. Akabori, S. Yamada
    “Spin-polarized transport in adiabatic quantum point contact with strong Rashba spin–orbit interaction”
    Solid State Comm., Vol. 136, pp. 479-483 (2005). 

  51. M. Akabori, K. Suzuki, S. Yamada
    “Channel Width Dependence of Spin Polarized Transports in NiFe/InGaAs Hybrid Two-Terminal Structures”
    J. Superconductivity, Vol. 18, pp. 367-370 (2005). 

  52. J. Takeda, M. Akabori, J. Motohisa, R. Nötzel, T. Fukui
    “Selective-area MOVPE fabrication of GaAs hexagonal air-hole arrays on GaAs (111)B substrates using flow-rate modulation mode”
    J. Nanotechnology, Vol. 16, pp. 2954-2957 (2005). 

  53. T. Kakegawa, M. Akabori, S. Yamada
    “Spin-Splitting Transport in Narrow-Gap Heterojunction Narrow Wires”
    J. Superconductivity, Vol. 18, pp. 229-232 (2005). 

  54. S. Yamada, T. Ohnishi, T. Kakegawa, M. Akabori, T. Suzuki, H. Sugiura, F. Nakamura, E. Yamaguchi, H. Kawai
    “High-quality two-dimensional electron gas at large scale GaN/AlGaN wafer interface prepared by mass production MOCVD systems”
    Solid State Com., Vol. 133, pp. 647-649 (2005).

  55. T. Kakegawa, M. Akabori, S. Yamada
    “Study of spin transport in In0.75Ga0.25As/ In0.75Al0.25As narrow wires”
    Sci. Tech. Advanced Mat., Vol. 5, pp. 309-312 (2004). 

  56. M. Akabori, S. Yamada
    “Spin polarized transports through a narrow-gap semiconductor wire with ferromagnetic contacts formed on InAlAs step-graded buffer layers”
    Sci. Tech. Advanced Mat., Vol. 5, pp. 305-308 (2004).
     
  57. T. Kita, T. Kakegawa, M. Akabori, S. Yamada
    “Spin-polarized transport in Rashba quantum point contacts”
    Physica E, Vol. 22, pp. 464-467 (2004).

  58. T. Sato, M. Akabori, S. Yamada
    “High-quality highly mismatched InSb films grown on GaAs substrate via thick AlSb and InxAl1-xSb step-graded buffers”
    Physica E, Vol. 21, pp. 615-619 (2004). 

  59. M. Akabori, J. Takeda, J. Motohisa, T. Fukui
    “InGaAs Nano-pillar Array Formation on Partially Masked InP (111)B by Selective Area MOVPE Growth for Two-dimensional Photonic Crystal Application”
    Nanotechnology, Vol. 14, pp. 1071-1074 (2003). 

  60. P. Mohan, F. Nakajima, M. Akabori, J. Motohisa, T. Fukui
    “Fabrication of semiconductor Kagome lattice structure by selective area metalorganic vapor phase epitaxy”
    Appl. Phys. Lett., Vol. 83, No. 4, pp. 689-691 (2003). 

  61. J. Takeda, M. Akabori, J. Motohisa, T. Fukui
    “Formation of AlxGa1-xAs periodic array of micro hexagonal pillars and air Holes by selective area MOVPE”
    Appl. Surf. Sci., Vol. 190, pp. 236-241 (2002).
     
  62. T. Ishihara, S. Lee, M. Akabori, J. Motohisa, T. Fukui
    “Dependence of In content of InxGa1-xAs quantum dots grown along GaAs multiatomic steps by MOVPE”
    J. Cryst. Growth, Vol. 237-239, pp. 1476-1480 (2002). 

  63. M. Akabori, J. Takeda, J. Motohisa, T. Fukui
    “Selective area MOVPE growth of two-dimensional photonic crystals having an air-hole array and its application to air-bridge-type structures”
    Physica E, Vol. 13, pp. 446-450 (2002). 

  64. S. Lee, M. Akabori, T. Shirahata, K. Takada, J. Motohisa, T. Fukui
    “The initial stage of InGaAs growth by MOVPE on multiatomic-stepped GaAs structures”
    J. Cryst. Growth, Vol. 231, pp. 75-81 (2001). 

  65. J. Motohisa, C. Tazaki, M. Akabori, T. Fukui
    “Incorporation mechanism of Si during delta-doping in GaAs singular and vicinal surfaces”
    J. Cryst. Growth, Vol. 221, pp. 47-52 (2000).

  66. M. Akabori, J. Motohisa, T. Fukui
    “Large Positive Magnetoresistance in Periodically Modulated Two Dimensional Electron Gas Formed on Self-organized GaAs Multiatomic Steps”
    Physica E, Vol. 7, pp. 766-771 (2000).

  67. T. Ogawa, M. Akabori, J. Motohisa, T. Fukui
    “Effect of growth interruption time and growth temperature on the natural formation of InGaAs/AlGaAs quantum disk structures on GaAs (311)B substrates”
    J. Appl. Phys., Vol. 87, pp. 745-749 (2000). 

  68. J. Motohisa, C. Tazaki, T. Irisawa, M. Akabori, T. Fukui
    “Selective Incorporation of Si along Step Edges during Delta-doping on MOVPE-growth GaAs (001) Vicinal Surfaces”
    J. Elec. Mat., Vol. 29, pp. 140-145 (2000). 

  69. T. Ogawa, M. Akabori, J. Motohisa, T. Fukui
    “Self organization in InGaAs/AlGaAs quantum disk structures on GaAs (311)B substrates”
    Microelectronic Engineering, Vol. 47, pp. 231-233 (1999). 

  70. T. Ogawa, M. Akabori, J. Motohisa, T. Fukui
    “Surface deformation phenomena induced by electron-beam irradiation in strained InGaAs/AlGaAs layers on GaAs (100) and (311)B substrates”
    Physica B, Vol. 270, pp. 313-317 (1999). 

  71. K. Yamatani, M. Akabori, J. Motohisa, T. Fukui
    “Characterization of Potential Modulation in Novel Lateral Surface Superlattices Formed on GaAs Multiatomic Steps”
    Jpn. J. Appl. Phys., Vol. 38, pp. 2562-2565 (1999).

  72. T. Ogawa, M. Akabori, J. Motohisa, T. Fukui
    “Real-Time Observation of Electron-Beam Induced Mass Transport in Strained InGaAs/AlGaAs Layers on GaAs (100) and (311)B Substrates”
    Jpn. J. Appl. Phys., Vol. 38, pp. 1040-1043 (1999). 

  73. M. Akabori, J. Motohisa, T. Fukui
    “Formation and characterization of modulated two-dimensional electron gas on GaAs multiatomic steps grown by metalorganic vapor phase epitaxy”
    J. Cryst. Growth, Vol. 195, pp. 579-585 (1998). 

  74. T. Irisawa, J. Motohisa, M. Akabori, T. Fukui
    “Delta-Doping and the Possibility of Wire-like Incorporation of Si on GaAs Vicinal Surfaces in Metalorganic Vapor Phase Epitaxial Growth”
    Jpn. J. Appl. Phys., Vol. 37, pp. 1514-1517 (1998). 

  75. M. Akabori, J. Motohisa, T. Irisawa, S. Hara, J. Ishizaki, T. Fukui
    “A Novel Electron Wave Interference Device Using Multiatomic Steps on Vicinal GaAs Surfaces Grown by Metalorganic Vapor Phase Epitaxy: Investigation of Transport Properties”
    Jpn. J. Appl. Phys., Vol. 36, pp. 1966-1971 (1997).

  76. J. Motohisa, M. Akabori, S. Hara, J. Ishizaki, K. Ohkuri, T. Fukui
    “Theoretical and experimental investigation of an electron interference device using multiatomic steps on vicinal GaAs surfaces”
    Physica B, Vol. 227, pp. 295-298 (1996).