Home Page of Koji Azuma

NTT Basic Reserch Laboratories
Optical Science Laboratory
Quantum Optical State Control Research Group
3-1 Morinosato Wakamiya, Atsugi, Kanagawa, 243-0198, Japan
E-mail: azuma.koji[put “@” here]lab.ntt.co.jp

Biography

2010-	Researcher in NTT Basic Research Laboratories.
2007-2010	Graduate School of Engineering Science, Osaka University.
	Awarded the degree of DSc for a thesis entitled
	"Long-distance quantum communication with remote nondestructive parity measurement."
	Supervised by Professor Nobuyuki Imoto.
2005-2007	Department of Applied Physics, University of Tokyo.
	Awarded the degree of MSc for a thesis entitled
	"Roles of entanglement in quantum operations."
	Supervised by Professor Naoto Nagaosa.
-2005	School of Engineering Science, Osaka University.

Fellowships

2007-2010	Research Fellow of the Japan Society for the Promotion of Science (DC1).

Research Interests

Quantum information theory:
• What can we do under the laws of nature?
• What is the role of quantum entanglement in information processing?
• What kind of information could exist in nature?

Realization of quantum information processing:

• How can we realize quantum computer and communication?
• What is the limit of realistic quantum computer and communication?

Papers

1. Koji Azuma and Go Kato,
   "Optimal entanglement manipulation via coherent-state transmission,"
   arXiv:1108.2747.　
   
2. Koji Azuma, Hitoshi Takeda, Masato Koashi, and Nobuyuki Imoto,
   "Quantum repeaters and computation by a single module,"
   arXiv:1003.0181.　
   
3. Koji Azuma, Naoya Sota, Masato Koashi, and Nobuyuki Imoto,
   "Tight bound on coherent-state-based entanglement generation over lossy channels,"
   Phys. Rev. A 81, 022325 (2010),
   arXiv:0908.2735.　
   
4. Koji Azuma, Naoya Sota, Ryo Namiki, Sahin Kaya Ozdemir, Takashi Yamamoto, Masato Koashi, and Nobuyuki Imoto,
   "Optimal entanglement generation for efficient hybrid quantum repeaters,"
   Phys. Rev. A 80, 060303(R) (2009),
   arXiv:0811.3100.　
   
5. Koji Azuma, Masato Koashi, and Nobuyuki Imoto,
   "Quantum catalysis of information,"
   arXiv:0804.2426.　
6. Koji Azuma, Masato Koashi, Hosho Katsura and Nobuyuki Imoto,
   "Quantum cloning with nonlocal assistance: Complement of Jozsa's stronger no-cloning theorem,"
   quant-ph/0604009.　
   
7. Koji Azuma, Junichi Shimamura, Masato Koashi, and Nobuyuki Imoto,
   "Probabilistic cloning with supplementary information,"
   Phys. Rev. A 72, 032335 (2005),
   quant-ph/0505207.　
   
8. Kazuto Ohshima and Koji Azuma,
   "Proper magnetic fields for nonadiabatic geometric quantum gates in NMR,"
   Phys. Rev. A 68, 034304 (2003),
   quant-ph/0305109.　

International Conferences/Workshop Presentations

1. Go Kato and Koji Azuma,
   "Optimal entanglement manipulation via coherent-state transmission,"
   QIP2012 (Poster),
   Montreal (Canada),
   2011/12/12.
2. Koji Azuma,
   "Quantum repeaters and computation built on a single module,"
   Quantum Science Symposium 2011 (Invited),
   Massachusetts (USA),
   2011/9/27.
3. Koji Azuma and Go Kato,
   "Optimal coherent-state-based entanglement generation,"
   QIPC2011 (Poster),
   Zurich (Switzerland),
   2011/9/7,9.
4. Koji Azuma, Hitoshi Takeda, Masato Koashi, and Nobuyuki Imoto,
   "Quantum repeaters and computation by a single module: remote nondestructive parity measurement,"
   QIP2011 (Poster),
   Sentosa (Singapore),
   2011/1/11.
5. Koji Azuma, Naoya Sota, Masato Koashi, and Nobuyuki Imoto,
   "Optimal bound on coherent-state-based entanglement generation over lossy channels,"
   2nd ICQIT (Poster),
   NII (Japan),
   2010/10/21.
6. Koji Azuma, Naoya Sota, Masato Koashi, and Nobuyuki Imoto,
   "Tight bound on coherent-state-based entanglement generation over lossy channels,"
   UQCC 2010 (Poster),
   ANA Intercontinental Tokyo (Japan),
   2010/10/19.
7. Koji Azuma, Hitoshi Takeda, Masato Koashi, and Nobuyuki Imoto,
   "Quantum repeaters and computation by a single module: Remote nondestructive parity measurement,"
   AQIS'10 (Oral),
   University of Tokyo (Japan),
   2010/8/29.
8. Koji Azuma, Naoya Sota, Ryo Namiki, Sahin Kaya Ozdemir, Takashi Yamamoto, Masato Koashi, and Nobuyuki Imoto,
   "Optimal entanglement generation in hybrid quantum repeaters,"
   Conference on Quantum Information & Quantum Control III (Poster),
   Fields Institude (Canada),
   2009/8/25.
9. Koji Azuma, Masato Koashi, and Nobuyuki Imoto,
   "Accessing genuinely quantum information without causing disturbance,"
   QIP 2009 (Poster),
   Santa Fe Convention Center (USA),
   2009/1/14.
10. Koji Azuma, Masato Koashi, and Nobuyuki Imoto,
    "Quantum catalysis of information,"
    International Symposium on Physics of Quantum Technology (Poster),
    Nara Prefectural New Public Hall (Japan),
    2008/11/27.
11. Koji Azuma,
    "Quantum catalysis of information and its implications,"
    GSIS workshop on quantum information theory (Invited),
    Tohoku University (Japan),
    2008/11/7.
12. Koji Azuma, Masato Koashi, and Nobuyuki Imoto,
    "Quantum catalysis of information,"
    QCMC 2008 (Poster),
    University of Calgary (Canada),
    2008/8/20.
13. Koji Azuma, Masato Koashi, and Nobuyuki Imoto,
    "Quantum catalysis of information,"
    APS march meeting (Oral),
    Morial Convention Center (USA),
    2008/3/11.
14. Koji Azuma, Masato Koashi, Hosho Katsura and Nobuyuki Imoto,
    "Quantum cloning with nonlocal assistance: Complement of Jozsa's stronger no-cloning theorem,"
    Handai Nano Symposium (Poster),
    Osaka University (Japan),
    2007/9/27.
15. Koji Azuma, Masato Koashi, Hosho Katsura and Nobuyuki Imoto,
    "Quantum cloning with nonlocal assistance: Complement of Jozsa's stronger no-cloning theorem,"
    AQIS 2007 (Oral),
    Shiran Kaikan, Kyoto University (Japan),
    2007/9/4.
16. Koji Azuma, Masato Koashi, and Nobuyuki Imoto,
    "What kind of assistance enables quantum cloning?,"
    APS march meeting (Oral),
    Colorad Convention Center (USA),
    2007/3/8.
17. Koji Azuma, Junichi Shimamura, Masato Koashi, and Nobuyuki Imoto,
    "Probabilistic cloning with supplementary information,"
    COE-Kakenhi workshop on quantum information theory and Quantum statistical inference (Oral),
    The University of Tokyo (Japan),
    2005/11/18.
18. Koji Azuma, Junichi Shimamura, Masato Koashi, and Nobuyuki Imoto,
    "Probabilistic cloning with supplementary information,"
    EQIS 2005 (Poster),
    The National Museum of Emerging Science and Innovation (Japan),
    2005/8/29
19. Koji Azuma, Junichi Shimamura, Masato Koashi, and Nobuyuki Imoto,
    "Probabilistic cloning with supplementary information,"
    IQEC and CLEO-PR2005 (Poster),
    The Nippon Toshi Center Hotel (Japan),
    2005/7/15.

Internal Conferences/Workshop Presentations

1. Koji Azuma, and Go Kato
   "コヒーレント状態伝送に基づく最適量子もつれ生成"
   JPS annual meeting (Oral),
   Kwansei Gakuin University (Japan),
   2012/3/24.
2. Go Kato, and Koji Azuma
   "ユニタルチャンネルを通じた量子もつれ生成のLOCC限界"
   JPS annual meeting (Oral),
   Kwansei Gakuin University (Japan),
   2012/3/24.
3. Koji Azuma, Hitoshi Takeda, Masato Koashi, and Nobuyuki Imoto,
   "Limits on single-error-type entanglement generation based on coherent states,"
   JPS autumn meeting (Oral),
   University of Toyama (Japan),
   2011/9/21.
4. Koji Azuma, Hitoshi Takeda, Masato Koashi, and Nobuyuki Imoto,
   "Coherent-state-based entanglement generation via separable operations, local operations and classical communication, and an experimentally-oriented protocol,"
   QIT24 (Oral),
   Tokyo Institute of Technology (Japan),
   2011/5/14.
5. Koji Azuma, Hitoshi Takeda, Masato Koashi, and Nobuyuki Imoto,
   "Quantum repeaters and computation by remote nondestructive parity measurement,"
   The 5th Interdisciplinary Workshop 「Quantum optics in various physical system」 (Invited),
   Kyoto Hyatt Regency Hotel (Japan),
   2011/3/22.
6. Koji Azuma, Hitoshi Takeda, Masato Koashi, and Nobuyuki Imoto,
   "Quantum repeaters and computation by a single module,"
   QIT23 (Oral),
   Tokyo University (Japan),
   2010/11/16.
7. Koji Azuma, Hitoshi Takeda, Masato Koashi, and Nobuyuki Imoto,
   "Quantum repeaters and computation by a single module,"
   JPS autumn meeting (Oral),
   Osaka Prefecture University (Japan),
   2010/9/23.
8. Toshiyuki Yamagata, Koji Azuma, Toshiyuki Tashima, Takashi Yamamoto, Masato Koashi, and Nobuyuki Imoto
   "原子集団メモリーを用いた量子リピーターにおける初期化時間の影響,"
   QIT21 (Poster),
   University of Elector-Communications (Japan),
   2009/11/4.
9. Yoritoshi Adachi, Yuya Kobayashi, Koji Azuma, Takashi Yamamoto, Masato Koashi, and Nobuyuki Imoto
   "エンタングルメントに基づく量子鍵配送における受動基底選択とその効率解析,"
   JPS autumn meeting (Oral),
   Kumamoto University (Japan),
   2009/9/27.
10. Hitoshi Takeda, Koji Azuma, Naoya Sota, Masato Koashi, and Nobuyuki Imoto
    "Coherent-state-based entanglement generation by middle-point measurement,"
    JPS autumn meeting (Oral),
    Kumamoto University (Japan),
    2009/9/25.
11. Koji Azuma, Naoya Sota, Masato Koashi, and Nobuyuki Imoto
    "Tight bound on coherent-state-based entanglement generation over lossy channels,"
    JPS autumn meeting (Oral),
    Kumamoto University (Japan),
    2009/9/25.
12. Hitoshi Takeda, Koji Azuma, Naoya Sota, Masato Koashi, and Nobuyuki Imoto
    "Coherent-state-based entanglement generation by middle-point measurement,"
    Symposium on Atomic, Molecular, and Optical Sciences (Poster),
    Osaka University (Japan),
    2009/6/12.
13. Koji Azuma, Naoya Sota, Ryo Namiki, Sahin Kaya Ozdemir, Takashi Yamamoto, Masato Koashi, and Nobuyuki Imoto
    "Optimal entanglement generation in hybrid quantum repeaters,"
    Symposium on Atomic, Molecular, and Optical Sciences (Poster),
    Osaka University (Japan),
    2009/6/12.
14. Koji Azuma, Naoya Sota, Masato Koashi, and Nobuyuki Imoto
    "Tight bound on coherent-state-based entanglement generation over lossy channels,"
    QIT 20 (Oral),
    Hiroshima University (Japan),
    2009/5/21.
15. Naoya Sota, Koji Azuma, Ryo Namiki, Sahin Kaya Ozdemir, Takashi Yamamoto, Masato Koashi, and Nobuyuki Imoto
    "Optimal entanglement generation for efficient hybrid quantum repeaters,"
    QIT 19 (Oral),
    Osaka Prefecture University (Japan),
    2008/11/21.
16. Naoya Sota, Koji Azuma, Ryo Namiki, Sahin Kaya Ozdemir, Takashi Yamamoto, Masato Koashi, and Nobuyuki Imoto
    "コヒーレント光を用いた量子メモリー間でのエンタングルメント生成方式の提案,"
    JPS autumn meeting (Oral),
    Iwate University (Japan),
    2008/9/20.
17. Koji Azuma, Masato Koashi, and Nobuyuki Imoto,
    "Quantum catalysis of information,"
    QIT 18 (Oral),
    The University of Tokyo (Japan),
    2008/5/23.
18. Koji Azuma, Masato Koashi, and Nobuyuki Imoto,
    "Catalytic impartment and absorption of quantum information,"
    JPS autumn meeting (Oral),
    Hokkaido University (Japan),
    2007/9/24.
19. Koji Azuma, Masato Koashi, Hosho Katsura and Nobuyuki Imoto,
    "Quantum cloning with nonlocal assistance: Complement of Jozsa's stronger no-cloning theorem,"
    JPS autumn meeting (Oral),
    Chiba University (Japan),
    2006/9/25.
20. Koji Azuma, Masato Koashi, Hosho Katsura and Nobuyuki Imoto,
    "Quantum cloning with nonlocal assistance,"
    QIT 14 (Poster),
    Ookayama Campus, Tokyo Institute of Technology (Japan),
    2006/5/29.
21. Koji Azuma, Junichi Shimamura, Masato Koashi, and Nobuyuki Imoto,
    "Probabilistic cloning with supplementary information,"
    JPS annual meeting (Oral),
    Ehime University and Matsuyama University (Japan),
    2006/3/29.
22. Koji Azuma, Junichi Shimamura, Masato Koashi, and Nobuyuki Imoto,
    "Probabilistic cloning with supplementary information,"
    QIT 12 (Poster),
    NTT Basic Research Laboratories (Japan),
    2005/5/13.

Lectures

1. 東　浩司,
   "量子通信の可能性―基礎から現状まで",
   群馬工業高等専門学校　平成23年度電子メディア工学科講演会,
   群馬工業高等専門学校， 2011/4/26.

Prizes

1. Tanaka prize (a prize for excellent master theses),
   2007/3/22.

Academic Societies

1. Phys. Soc. Japan, Student member.

Links

1. NTT Basic Research Laboratories.　
2. Quantum Optical State Control Research Group.