1 / 24

A wonderland of 1,2,3-dimensional molecular conductors – Fermiology and nonlinear optics

ISCOM2005 September 11-16, 2005, Key West, Florida, USA. A wonderland of 1,2,3-dimensional molecular conductors – Fermiology and nonlinear optics. Madoka TOKUMOTO a,b,c a National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan

hanley
Download Presentation

A wonderland of 1,2,3-dimensional molecular conductors – Fermiology and nonlinear optics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ISCOM2005 September 11-16, 2005, Key West, Florida, USA A wonderland of 1,2,3-dimensional molecular conductors – Fermiology and nonlinear optics Madoka TOKUMOTOa,b,c aNational Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan bTokyo University of Science, cCREST-JST Nonlinear optical properties of carbon nanotubes and its application as saturable absorption device for optical fiber communication Wonderland

  2. Outline • Introduction: Historical background of “Wonderland” and “BT&T” • Fermiology of 2D-organic molecular conductors (ET)2X, studied by Brooks method at FBNML • Fermiology of 3D-molecular conductors Single-component molecular metal Ni(tmdt)2, studied by AFM microcantilever at NHMFL • Fermiology of 1D-molecular conductors Carbon nanotubes, studied by STM • Nonlinear Optics of Carbon Nanotubes Saturable Absorber for Femtseconds Pulse Laser • Summary

  3. What is “Wonderland”? Organic Superconductivity, Ed. by V.Z. Kresin and W.A. Little (Plenum Press, 1990) pp.167-190 ; Proceedings of the International Workshop on Organic Superconductivity (May 20-24, 1990, South Lake Tahoe, Calif.)

  4. Fermiology of organic conductors started in 1988 Magnetic quantum oscillations in magnetoresistsnce SdH: Shubnikov-de Haas effect in magnetization dHvA: de Haas-van Alphen effect (M. Tokumoto et al. in “Organic Superconductors” (1990) p.168) In November 1989, I visited Francis Bitter National Magnet Laboratory, MIT, for the first time, and started collaboration with Prof. James S. Brooks and his group at Boston University 1) (ET)2KHg(SCN)4 (ETL) 2) q-(ET) 2I3 (M. Tamura) 3) b”-(ET)2AuBr2 (A. Ugawa)

  5. k-(ET)2Cu(NCS)2

  6. How it started? In November 1989, I visited Francis Bitter National Magnet Laboratory, MIT, for the first time, and started a longtime collaboration with Prof. James S. Brooks and his group at Boston University During my stay, we obtained new results on 1) (ET)2KHg(SCN)4 (ETL) 2) q-(ET) 2I3 (M. Tamura) 3) b”-(ET)2AuBr2 (A. Ugawa)

  7. What is Brooks Method?Both SdH & dHvA effects J. S. Brooks et al., Rev. Sci. Instrum. 58, 117-121 (1987)

  8. de Haas-van Alphen Effect q-(ET) 2I3 (M. Tamura) M. Tokumoto et al., Solid State Commun., 75, 439 (1990)

  9. Prof. Kagoshima said “Now, it’s all over. Nothing is left to do, about this material.” Nevertheless, I decided to grow crystals by ourselves at ETL.

  10. (ET)2MHg(SCN)4 Spin-splitting of SdH effect in (ET)2KHg(SCN)4 (ET)2MHg(SCN)4M=K, Rb, Tl (Charge Density Wave?)NH4(Superconductor)It turned out to be an extremely fruitful & wonderful system. M. Tokumoto et al., J. Phys. Soc. Jpn., 59, 2324 (1990)

  11. What is “BT&T”? Boston, Tsukuba and Tokyo Boston Univ./FBNML (Boston), Electrotechnical Lab. (Tsukuba), NRIM (Drs. Aoki & Uji) Tokyo NRIM (Tokyo  Tsukuba) FBNML  NHMFL (Tallahassee) Prof. Brooks BU  FSU (Tallahassee) Boston, Tallahassee and Tsukuba

  12. BT&T and other collaborations • 1989 - 1999 BEDT-TTF(ET) salts with 2D-Fermi surface (ET)2MHg(SCN)4M=K, Rb, Tl, NH4 2) Single-component [Ni(tmdt)2] (Dr. H. Tanaka) 3D-Fermi surface • 1994 - 1998 l-(BETS)2FeCl4 (with Profs. H. & A. Kobayashi) “Filed-induced-highly-conducting-state” (Drs. Brossard, Cassoux) • 2000 - present (with Profs. H. & A. Kobayashi) 1) BETS salts l,k-(BETS)2FeX4 (X=Cl,Br) 2D-Magnetic conductors “Filed-induced superconductivity”(Drs.Uji, Balicas)

  13. Observation of 3-D Fermi Surfaces in a Single-Component Molecular Conductor, [Ni(tmdt)2] Hisashi Tanaka, Madoka Tokumoto, S. Ishibashi, David Graf, E. S. Choi, J.S. Brooks, S. Yasuzuka, Y. Okano, Hayao Kobayashi, Akiko Kobayashi J. Am. Chem. Soc. 126, 10518 (2004) Application ofAFM microcantilever to torque magnetometrywas developedby E. Omichi and T. Osada, Rev. Sci. Instrum, 73, 3022 (2002)

  14. Residual Resistivity Ratio (RRR) = r(300K)/r(low T) ~ 2.5 Wonderland H. Tanaka, Y. Okano, H. Kobayashi, W. Suzuki, A. Kobayashi, Science 291, 285 (2001)

  15. Atomic-resolution STM Images of Carbon Nanotubes A. Hassanien Lattice Image  Wavefunction  Charge Density Wave with Fermi wavevector (kF)

  16. Electronic Structure and Fermi Surface of Carbon Nanotubes

  17. FFT Bragg spot Fermi point

  18. Optical property of Carbon NanotubesDensity of States（DOS) and Absorption semiconducting metallic Energy (eV) Energy (eV) DOS (arb.unit) DOS (arb. Unit) Typical Density of States (DOS) for semiconducting(left) and metallic(right) single-wall carbon nanotubes H.Kataura et al. Synthetic Metals 103 (1999) 2555

  19. Saturable Absorption: Principle and Properties A saturable absorber has an absorption coefficient which is a non-linear function of I: As the intensity is increase beyond Is, the absorption decreases and the system becomestransparent. • Strong light • excites many electrons • saturates absorption • Happen easily, when • oscillator strength is large • Important properties • Saturation intensity • Recovery time (<1ps) • Transmittance change • Spectral change absorption absorption relaxation Absorption Coeff. Absorption Intensity

  20. Applications SINGLE WALL CARBON NANOTUBES (SWCNT) FOROPTICAL FIBER COMMUNICATION Saturable Absorptionof SWCNT at aboutλ=1.55 µm Saturable Absorber has Potential Applications • all-optical switching devices [1,2, etc.] • saturable absorbers for mode-lock lasers [3] • ASE noise suppression filters for optical amplifiers [4] [1] Y. Sakakibara et al., Japan Patent No, 2001-320383, filed on 18 October 2001; Y. Sakakibara et al. Jpn. J. Appl. Phys. 42 (2003) L 494 [2] Y.-C. Chen, et al., Appl.Phys.Lett. 81 (2002) 975 [3] S. Y. Set et al., Proceedings of Optical Fiber Communication ’03 (OFC’03), Atlanta, Georgia, March 23-28, 2003, pd. 44. [4] Y. Sakakibara et al., Proceedings of of 29- th European conference on Optical Communication (ECOC-03), Rimini, Italy, 21-25 September 2003, Th 4.2.5

  21. World shortest 206 fs EDF laser with SWNT based passive mode-locker EDFA P= 1.55 mW, Repetition 22.91 MHz isolator output 50:50coupler isolator SWNT-PVA CNT-PVA saturable absorber for mode-locked pulse lasers

  22. Summary • Introduction: Historical background of “Wonderland” and “BT&T” • Fermiology of 2D-organic molecular conductors (ET)2X, studied by Brooks method at FBNML • Fermiology of 3D-molecular conductors Single-component molecular metal Ni(tmdt)2, studied by AFM microcantilever at NHMFL • Fermiology of 1D-molecular conductors Carbon nanotubes, studied by STM • Nonlinear Optics of Carbon Nanotubes Saturable Absorber for Femtseconds Pulse Laser  P1-7

  23. Acknowledgements James S. Brooks and his group at Boston University / Francis Bitter National Magnet Lab. Florida State University / National High Magnetic Field Lab. (A.G. Swanson, C.C. Agosta, S.T. Hannahs, …… … L. Balicas, …. , D. Graf, E.S. Choi) H. Anzai, N. Kinoshita, K. Murata, … M. Tamura, A. Ugawa, H. Tajima, H. Kuroda, … G. Saito H. Kobayashi, A. Kobayashi, H. Tanaka, S. Ishibashi, … S. Uji, S. Yasuzuka, E. Omichi, … A. Hassanien, Y. Sakakibara, H. Kataura, … Thank you for your attention!

More Related