Nanophotonics Laboratory

• “Deterministic coupling of site-controlled quantum emitters in monolayer WSe2 to plasmonic nanocavities” Y. Luo, G.D. Shepard, J.V. Ardelean, D.A. Rhodes, B. Kim, K. Barmak, J. Hone, and S. Strauf, Nature Nanotechnology 13, 1137 (2018)

• “Suppresion of exciton dephasing in sidewall-functionalized carbon nanotubes embedded into metallo-dielectric antennas”, K. Shayan, X. He, Y. Luo, C. Rabut, X. Li, N. Hartmann, J.L. Blackburn, S.K. Doorn, H. Htoon, and S. Strauf, Nanoscale 10, 12631 (2018).

• “Remarkable long-term stability of nanoconfined metal-halide perovskite crystals against degradation and polymorph transitions”, X. Kong, K. Shayan, S. Lee, C. Ribeiro, S. Strauf, and S. Lee, Nanoscale 10, 8320 (2018).

• “Trion-species-resolved quantum beats in MoSe2”, G.D. Shepard, J.V. Ardelean, D.Rhodes, X.Y. Zhu, C. Hone, S. Strauf, ACS Nano 11, 11550 (2017), DOI:10.1021/acsnano.7b06444

• “Broadband light collection efficiency enhancement of carbon nanotube excitons coupled to metallo-dielectric antennas”, K. Shayan, C. Rabut, X. Kong, X. Li, Y. Luo, K.S. Mistry, J.L. Blackburn, S. Lee, and S. Strauf, ACS Photonics 5, 289 (2017),DOI:10.1021/acsphotonics.7b00786

• “Near-unity quantum yield from carbon nanotube excitons coupled to plasmonic nanocavities”, Y. Luo, E.D. Ahmadi, K. Shayan, Y. Ma, K. Mistry, C. Zhang, J. Hone, J.L. Blackburn, and S. Strauf, Nature Communications 8, 1413 (2017).

• “Low Temperature Single Carbon Nanotube Spectroscopy of sp3 Quantum Defects”, X. He, B. Gifford, N. F. Hartmann, R. Ihly, X. Ma, S. Kilina, Y. Luo, K. Shayan, S. Strauf, J.L. Blackburn, S. Tretiak, S.K. Doorn, and H. Htoon, ACS Nano 11, 10785 (2017), doi:10.1021/acsnano.7b03022

• “Non-magnetic quantum emitters in boron nitride with ultra-narrow and sideband-free emission spectra”, X. Li, G.D. Shepard, A. Cupo, N. Camporeale, K. Shayan, Y. Luo, V. Meunier, and S. Strauf, ACS Nano 11, 6652 (2017), doi:10.1021/acsnano.7b00638

• “Approaching the intrinsic photoluminescence linewidth in transition metal dichalcogenide monolayers”, O.A. Ajayi, J.V. Ardelean, G.D. Shepard, J. Wang, A. Antony, T. Taniguchi, K. Watanabe, T.F. Heinz, S. Strauf, X.-Y. Zhu, and J. Hone, 2D Materials 4, 031011 (2017), doi: 10.1088/2053-1583/aa6aa1

• “Nanobubble induced formation of quantum emitters in monolayer semiconductors”, G.D. Shepard, O.A. Ajayi, X. Li, X.-Y. Zhu, and J. Hone, S. Strauf, 2D Materials 4, 021019 (2017), doi:10.1088/2053-1583/aa629d

• “Tunable multipole resonances in plasmonic crystals made by four-beam holographic lithography”, Yue Luo, Xiangzhi Li, Xi Zhang, Stephen Prybolsky, Gabriella D. Shepard, and Stefan Strauf, Applied Physics Letters 108 (5), 053105 (2016).

• “Strong Acoustic Phonon Localization in Copolymer-Wrapped Carbon Nanotubes”, Ibrahim Sarpkaya, Ehsaneh D. Ahmadi, Gabriella D. Shepard, Kevin S. Mistry, Jeffrey L. Blackburn, and Stefan Strauf, ACS Nano 9, 6383 (2015).

• “Active Bandgap Tuning of Materials for Tunable Photodetection Applications”, Vikram Patil, Eui-Hyeok Yang, Stefan Strauf, U.S. Patent Serial #: US 8,878,120, B2 Nov. 4, (2014).

• “Prolonged Spontaneous Emission and Dephasing of Excitons in Air-Bridged SWCNTs”, Ibrahim Sarpkaya, Zhengyi Zhang, William Walden-Newman, James Hone, Chee-Wei Wong, and Stefan Strauf, The Electrochemical Society, Meeting Abstracts, Issue 30, Pages 1184-1184, (2014).

• “Intrinsic regime of exciton photophysics in ultra-clean carbon nanotubes bridging an air gap”, Ibrahim Sarpkaya, Zhengyi Zhang, William Walden-Newman, James Hone, Chee-Wei Wong, Stefan Strauf, Proc. SPIE 9168, Carbon Nanotubes, Graphene, and Associated Devices VII, 91680L (September 10, 2014).

• “Quantum light signatures from cavity-embedded carbon nanotubes”, Ibrahim Sarpkaya, William Walden-Newman, and Stefan Strauf, The Electrochemical Society, Meeting Abstracts #1154, 1 page, (2013).

• "Improved photoresponse with enhanced photoelectric contribution in fully suspended graphene photodetectors", V. Patil, S. Strauf, and EH Yang, Nature Scientific Reports 3, 2791 (2013).

• "Prolonged spontaneous emission and dephasing of localized excitons in air-bridged carbon nanotubes", I. Sarpkaya, Z. Zhang, W. Walden-Newman, X. Wang, J. Hone, C.W. Wong, and S. Strauf, Nature Communications 4, 3152 (2013).

• "Formation of triplet and quadruplet plasmonic nanoarray templates by holographic lithography", X. Zhang and S. Strauf, Applied Physics Letters 102, 093110 (2013).

• "Feedback and harmonic locking of slot-type optomechanical oscillators to external low-noise reference clocks", J. Zheng, Y. Li, N. Goldberg, M. McDonald, X. Luan, A. Hati, S. Strauf, T. Zelevinsky, D.A. Howe, and C.W. Wong, Applied Physics Letters 102, 141117 (2013).

• "Feedback locking of slot-type optomechanical oscillators to external low-noise reference clocks", J. Zheng, Y. Li, N. Goldberg, M. McDonald, A. Hati, M. Lu, S. Strauf, T. Zelevinsky, D.A. Howe, and C.W. Wong ", CLEO/QELS 2013, San Jose, CA, USA.

• "Quantum Light Signatures and Nanosecond Spectral Diffusion from Cavity-Embedded Carbon Nanotubes", W. Walden-Newman, I. Sarpkaya, and S. Strauf, Nano Letters 12, 1934 (2012).

• "Emission properties of photonic crystal nanolasers", book chapter by S. Strauf , in "Quantum optics with semiconductor nanostructures" (ed) F. Jahnke, Woodhead Publishing (July 2012), ISBN 0 85709 232 4

• "Quantum Transport in Graphene Nanoribbons with Realistic Edges", P. Hawkins, M. Begliarbekov, M. Zivkovic, S. Strauf, C. Search, J. of Phys. Chem. C 116, 18382 (2012).

• "Optical control of edge chirality in graphene", M. Begliarbekov, K. Sasaki, O. Sul, EH Yang, and S. Strauf, Nano Letters 11, 4874 (2011).

• "Holographic control of motive shape in plasmonic nanogap arrays" X. Zhang, M. Theuring, Q. Song, W. Mao, M. Begliarbekov and S. Strauf, Nano Letters 11, 2715 (2011)

• "Localized states and band bending in graphene antidot superlattices", M. Begliarbekov, O. Sul, J. Santanello, N. Ai, X. Zhang, EH Yang, and S. Strauf, Nano Letters 11, 1254 (2011).

• "Photonic Crystals: Lasing Woodpiles", S. Strauf, Nature Photonics 5, 72-74 (2011).

• "Silver nanoparticle doped TiO2 nanofiber dye sensitized solar cells", J. Li, X. Chen, N. Ai, J. Hao, Q. Chen, S. Strauf, and Y. Chi, Chem. Phys. Lett. 514, 141 (2011).

• "Suppression of Blinking and Enhanced Exciton Emission from Individual Carbon Nanotubes" N. Ai, W. Walden-Newman, Q. Song, S. Kalliakos, and S. Strauf", ACS Nano 5, 2664 (2011).

• "Single quantum dot nanolaser", Stefan Strauf and Frank Jahnke, Laser & Photonics Reviews 5, 607-633 (2011), also featured as"editors choice" and furthermore on MaterialsViews as a news story.

• "A Study on Nanoscale Carbon Nanotube Local Oxidation Lithography using an Atomic Force Microscope", K. Kumar, O. Sul, S. Strauf, F. Fisher, D. S. Choi, M. G. Prasad, and E. H. Yang, IEEE Trans. Nanotechnology 10, 849 (2011)

• "Quantum Inductance and High Frequency Oscillators in Graphene Nanoribbons", M. Begliarbekov, S. Strauf, and C.P. Search,

  Nanotechnology 22, 165203 (2011)

• "Graphene Optoelectronics based on Antidot Superlattices", S. Strauf and EH Yang, Micro and Nanotechnology Sensors, systems, and Applications III, Proc. SPIE, 8031 (2011).

• "Identifying Edge Chirality of Graphene Using Polarization Resolved µ-Raman Spectroscopy", M. Begliarbekov, O. Sul, S. Kalliakos, EH Yang, and S. Strauf ", CLEO/QELS 2011, Baltimore, MD, USA, paper QTuK7

2010

• "Aperiodic conductivity oscillations in quasi-ballistic graphene heterojunctions", M. Begliarbekov, O. Sul, N. Ai, E. H. Yang, S. Strauf,

  Appl. Phys. Lett.

   

  97

  ,

   

  122106 (2010).

• "Determination of Edge Purity in Bilayer Graphene Using micro-Raman Spectroscopy", M. Begliarbekov, O. Sul, S. Kalliakos, E. H. Yang, S. Strauf,

   

  Appl. Phys. Lett.

   

  97

  , 031908 (2010).

• "Cavity-QED: Lasing under strong coupling", S. Strauf,

   

  Nature Physics

   

  6

  , 244-245 (2010).

• "Quantum Optics: Towards efficient quantum sources", S. Strauf,

   

  Nature Photonics

   

  4

  , 132-134 (2010).

• "Transconductance and Coulomb blockade properties of in-plane grown carbon nanotube field effect transistors", N. Ai, O. Sul, M. Begliarbekov, Q. Song, K. Kumar, D. S. Choi, E. H. Yang, S. Strauf,

   

  Nanosci. Nanotechnol. Lett., vol.

   

  2

  , 73-78

   

  (2010).

• "A Systematic Study of Graphite Local Oxidation Lithography Parameters Using an Atomic Force Microscope", K. Kumar, S. Strauf, and E.H. Yang,

   

  Nanosci. Nanotechnol. Lett.

   

  2

  , 185-188 (2010).

• "Observation of Klein Tunneling in Top-Gated Graphene Transistors", M. Begliarbekov, O. Sul, C. Tsai, N. Ai, E. H. Yang and S. Strauf, (Apr 2010), Maryland, MD. Graphene Week 2010.

• "Nanoscale Graphene Lithography Using an Atomic Force Microscope", K. Kumar, S. Strauf, and E. H. Yang, (Apr 2010), Maryland, MD.

   

  Graphene Week 2010.

• "CVD-assisted Atomically Precision Cutting of Graphene Strips with Specific Boundaries", O. Sul, M. Begliarbekov, C. Tsai, Y. Kim, V. Patel, S. Strauf, and E. H. Yang, (Apr 2010), Maryland, MD.

   

  Graphene Week 2010.

• "Characterization of Graphitic Thin Films and Top-Gated Klein Transistors" M. Begliarbekov, O. Sul, N. Ai, C. Tsai, J. Heureaux, EH Yang, and S. Strauf, Gotham-Metro Condensed Matter Meeting,

   

  The New York Academy of Science, NYC, April 2010.

2009

• "Electro-optical Characterization of Individual Multiwall Carbon Nanotubes", talk, N. Ai, Y. T. Tsai, Q. Song, E. H Yang, D. S. Choi, and S. Strauf, SPIE Defense and Security Symposium, Micro- and Nanotechnology Sensors, Systems, and Applications, Orlando, FL, April 2009,

   

  Proc. SPIE

   

  7318

  , 73180Z (2009).

• "Carbon-based Nano Devices for Sensors, Actuators and Electronics", invited talk, E. H Yang, S. Strauf, F. Fisher, and D. S. Choi, SPIE Defense and Security Symposium, Micro- and Nanotechnology Sensors, Systems, and Applications, Orlando, FL, April 2009,

   

  Proc. SPIE 7318,

   

  731813

   

  (2009)

  .

• "Nanoscale Graphene and Carbon Nanotube Lithography using an Atomic Force Microscope", K. Kumar, O. Sul, Y. T. Tsai, S. Strauf, F. Fisher, D. S. Choi and E. H. Yang,

   

  ASME International Mechanical Engineering Congress and Exposition,

   

  Lake Buena Vista, FL

  ,

   

  ASME Conf. Proc.

   

  2009

  , 417 (2009)

  .

2008

• "High-frequency single photon sources", invited talk, S. Strauf, M.T. Rakher, N.G. Stolz, L.A. Coldren, P.M. Petroff, and D. Bouwmeester, 21st Annual Meeting of the IEEE/LEOS 2008, Newport Beach, CA, USA, DOI 10.1109/LEOS.2008. art. no.4688768, pp. 614-615, 2008.

2007

• "High-frequency single photon source with polarization control", S. Strauf, N. G. Stoltz, M. T. Rakher, L. Coldren, P. M. Petroff, and D. Bouwmeester, Nature Photon.

   

  1

  , 704-708 (2007).

• Cover story of Nature Photonics December issue 2007.

• See also Interview, "One by one",

   

  Nature Photon.

   

  1

  , 732 (2007)

  .

• Featured as News & Views article,

   

  Nature Photon.

   

  1

  , 686-687 (2007)

  .

• See also Research Highlights, "Mini mysteries",

   

  Nature

   

  450

  , p588

  .

• News story at

   

  PhysOrg:www.physorg.com/news116670671.html

  .

• One page article in "CT", German computer magazine, p.46, Jan.2008.

• "Evolution of the onset of coherence in a family of photonic crystal nanolasers", J.-S. Choi, M. T. Rakher, K. Hennessy, S. Strauf, A. Badolato, P. M. Petroff, E. Hu, D. Bouwmeester,

   

  Appl. Phys. Lett.

   

  91

  , 031108 (2007).

• "Efficient source of single photons from charge-tunable quantum dots in a micropillar cavity", invited talk, M.T. Rakher, S. Strauf, N.G. Stolz, L.A. Coldren, P.M. Petroff, and D. Bouwmeester

   

  CLEO/QELS 2007, Baltimore, MD, USA,

• "Cavity QED with QD in semiconductor microcavities", talk, M.T. Rakher, S. Strauf, Y. Choi, N.G. Stoltz, K.J. Hennessy, H. Kim, A. Badolato, L.A. Coldren, E.L. Hu, P.M. Petroff, and D. Bouwmeester, Photonics West 2007,

   

  Proc. of SPIE Vol. 6481, 648109 (2007)

  , San Jose, CA, USA.

2006

• "Self-Tuned Quantum Dot Gain in Photonic-Crystal Lasers", S. Strauf, K. Hennessy, M. T. Rakher, J.-S. Choi, A. Badolato, L.C. Andreani, P. M. Petroff, E. L. Hu, and D. Bouwmeester,

   

  Phys. Rev. Lett.

   

  96

  , 127404 (2006).

• News story at PhysOrg:

   

  www.ph

  ysorg.com/news64253705.html.

• Also featured as a Physics Update in

   

  Physics Today, June 2006, p.21

  .

• "Frequency control of photonic-crystal membrane resonators by mono-layer deposition", S. Strauf, M. T. Rakher, I. Carmeli, K. Hennessy, C. Meier, A. Badolato, M.J.A. DeDood, E. G. Gwinn, P. M. Petroff, E. L. Hu, and D. Bouwmeester,

   

  Appl. Phys. Lett.

   

  88

  , 043116 (2006).

• "Laser photon statistics in high- quantum-dot photonic-crystal nanocavities", talk, Y.-S. Choi, M. T. Rakher, K. Hennessy, S. Strauf, A. Badolato, P.M. Petroff, D. Bouwmeester, and E.L. Hu,

   

  CLEO/QELS 2006, Long Beach, CA, USA.

• "Quantum dot spontaneous emission lifetime modification in optical microcavities using oxide apertured micropillars", talk, N. G. Stoltz, M. Rakher, S. Strauf, D. Bouwmeester, P. M. Petroff, and L. A. Coldren, Photonics West 2006,

   

  Proc. of SPIE Vol. 6101, 6101W (2006)

  , San Jose, CA, USA.

2005

• "Photon Statistics from Coupled Quantum Dots", B. D. Gerardot, S. Strauf, M. J. A. DeDood, A. Bychkov, A. Badolato, K. Hennessy, E. L. Hu, D. Bouwmeester and P. M. Petroff,

   

  Phys. Rev. Lett.

   

  95

  , 137403 (2005).

• "High-Q optical microcavities using oxid apertured micropillars", N. G. Stoltz, M. T. Rakher, S. Strauf, A. Badolato, D. D. Loftgreen, P. M. Petroff, L. A. Coldren, and D. Bouwmeester,

   

  Appl. Phys. Lett.

   

  87

  , 031105 (2005).

• "Photon statistics of high-beta quantum dot photonic crystal laser", poster, Y.-S. Choi, M. T. Rakher, S. Strauf, K. Hennessy, A. Badolato, D. Bouwmeester, P. M. Petroff, and E. L. Hu,

   

  Int. Conf. on Photonic and Electromagnetic Structure 2005, VI, A29, (Crete, Greece, June 2005).

• "Photonic-crystal quantum-dot laser with ultra-low lasing threshold", hot topic talk, S. Strauf, K. Hennessy, M. T. Rakher, A. Badolato, P. M. Petroff, E. L. Hu, and D.
  Bouwmeester, Quantum Electronics and Laser Science Conf.

   

  (QELS) 2005, (IEEE Cat. No. 05CH37696), IEEE, Part Vol. 1, pp.404-6

  , Piscataway, NJ, USA.

2004

• "Photon Correlation Spectroscopy of Individual Quantum Dot Molecules", talk, B.D. Gerardot, S. Strauf, P.M. Petroff, M.J.A. DeDood, and D. Bouwmeester,

   

  APS March Meeting 2004, A36004G, Montreal, Canada.

• "Quantum optics of single quantum dots and single impurities", invited talk, P. Michler, M. Benyoucef, S. M. Ulrich, S. Strauf, Conf. on Laser and Electro-optics

   

  (CLEO) 2004, IEEE. Part vol.1, pp.2

  , Piscataway, NJ, USA.

• "Quantum optical studies on quantum dots and on individual acceptor bound excitons in a semiconductor", invited talk, S.M. Ulrich, M. Benyoucef, P. Michler, J. Wiersig, F. Jahnke, M. Kamp, A. Forchel, S. Strauf,

   

  20th Gen. Conf. Condensed Matter Division EPS (CMD20) 2004, F1H2

  , Prague, Czech Republic.

2003

• "Triggered polarization-correlated photon pairs from a single CdSe quantum dot", S. M. Ulrich, S. Strauf, P. Michler, G. Bacher, and A. Forchel,

   

  Appl. Phys. Lett.

   

  83

  , 1848 (2003)

  .

• "Generation of strongly polarization-correlated photon pairs by cascaded emission from individual CdSe/ZnSe quantum dots", S. M. Ulrich, S. Strauf, P. Michler, G. Bacher, and A. Forchel,

   

  phys. stat sol. (b)

   

  238

  , 607 (2003)

  .

• "Single-photon and photon-pair emission from CdSe/Zn(S,Se) quantum dots", S. Strauf, S. M. Ulrich, K. Sebald, P. Michler, T. Passow, D. Hommel, G. Bacher, and A. Forchel,

   

  phys. stat sol. (b)

   

  238

  , 321 (2003).

• "Triggered single-photon and photon-pair emission from acceptor bound excitons in a semiconductor", talk, P. Michler, S. Strauf, M. Klude, D. Hommel, G. Bacher, A. Forchel, Quantum Electronics and Laser Science Conf.

   

  (QELS) 2003, (IEEE Cat No.CH37420-TBR). OSA

  , pp.3, Washington, DC, USA.

2002

• "Quantum Optical Studies on Individual Acceptor Bound Excitons in a Semiconductor", S. Strauf, P. Michler, M. Klude, D. Hommel, G. Bacher, and A. Forchel,

   

  Phys. Rev. Lett.

   

  89

  , 177403 (2002).

• "Identische Photonen auf Bestellung" („Identical photons on demand"), invited news article, Stefan Strauf und Peter Michler,

   

  Physik Journal (DPG), Dezember 2002, S. 20,

• "Negatively charged donor centers in ultrathin ZnSe:N layers", S. Strauf, P. Michler, J. Gutowski, M. Klude, D. Hommel, D. Wolverson, and J.J. Davies,

   

  phys. stat. sol. (b)

   

  229

  , 245 (2002).

• "Displaced substitutional phosphorus acceptors in zinc selenide", D. Wolverson, J.J. Davies, S. Strauf, P. Michler, J. Gutowski, M. Klude, K. Ohkawa, D. Hommel, E. Tournie, and J.-P. Faurie,

   

  phys. stat. sol. (b)

   

  229

  , 257 (2002).

• "Triggered single-photon emission of individual acceptor-bound excitons in ZnSe:N", talk, S. Strauf, P. Michler, M. Klude, D. Hommel, G. Bacher, and A. Forchel, Proc. 26th Int. Conf. on the Physics of Semiconductors (ICPS) 2002, Edinburgh, UK.

2001

• "Direct evidence for the trigonal symmetry of shallow phosphorus acceptors in ZnSe", J.J. Davies, D. Wolverson, S. Strauf, P. Michler, J. Gutowski, M. Klude, K. Ohkawa, D. Hommel, E. Tournie, and J.-P. Faurie,

   

  Phys. Rev. B

   

  64

  , 205206 (2001).

• "Analysis of time-resolved donor-acceptor-pair recombination in MBE and MOVPE grown GaN:Mg", S. Strauf, S.M. Ulrich, P. Michler, J. Gutowski, T. Boettcher, S. Figge, S. Einfeldt, and D. Hommel,

   

  phys. stat. sol. (b)

   

  228

  , 379 (2001).

2000 

• „Shallow donors in ultra thin nitrogen-doped ZnSe layers - a novel or a disregarded compensation mechanism in II-VI device structures" S. Strauf, P. Michler, J. Gutowski, and D. Hommel,

   

  J. Cryst. Growth

   

  214/215

  , 497 (2000).

• "Temperature dependence of magnesium related optical transitions in GaN:Mg", poster, S. Strauf, S. Ulrich, P. Michler, J. Gutowski, V. Kirchner, S. Figge, S. Einfeldt and D. Hommel,

   

  Proc. Int. Workshop on Nitride Semiconductors (IWN) 2000, IPAP Conf. Series 1, (2000) p. 721

  .

1999

• "Optical spectroscopy of Mg- and C-related donor and acceptor levels in GaN grown by MBE", S. Strauf, P. Michler, J. Gutowski, U. Birkle, M. Fehrer, S. Einfeldt, and D. Hommel,

   

  phys. stat. sol. (b)

   

  216

  , 557 (1999).

• "Studies on carbon as alternative p-type dopant for gallium nitride", U. Birkle, M. Fehrer, V. Kirchner, S. Einfeldt, D. Hommel, S. Strauf, P. Michler, and J. Gutowski,

   

  MRS Internet J. Nitride Semiconductor Research 4, Art. No. G5.6, Suppl. 1 (1999)

  .

1998

• "Excitonic transitions in MBE grown h-GaN with cubic inclusions", S. Strauf, P. Michler, J. Gutowski, H. Selke, U. Birkle, S. Einfeldt, and D. Hommel,

   

  J. Cryst. Growth

   

  189/190

  , 682 (1998).

• "Analysis of time-resolved donor-acceptor-pair spectra of ZnSe:Li and ZnSe:N", P. Baeume, S. Strauf, J. Gutowski, M. Behringer, and D. Hommel, J. Cryst. Growth

   

  184/185

  , 531 (1998).

• "Donor-acceptor-pair recombination for impurity identification and analysis of cubic inclusions in Mg- and C-doped MBE grown hexagonal GaN", poster, S. Strauf, P. Michler, J. Gutowski, U. Birkle, S. Einfeldt, V. Kirchner, H. Heinke, and D. Hommel,

   

  Proc. of 2nd Int. Symposium on Blue Laser and Light Emitting Diodes (ISBLED), Chiba, Japan, Ohmsha Ltd. (1998), p. 574

  .

• "Characteristics of ZnSe:Ga:P layers grown by molecular beam epitaxy", talk, K. Ohkawa, P. Baeume, M. Fehrer, S. Strauf, J. Gutowski, D. Hommel, and G. Lippert,

   

  Proc. of 2nd Int. Symposium on Blue Laser and Light Emitting Diodes (ISBLED), Chiba, Japan, Ohmsha Ltd. (1998), p. 86

  .

1996

• "Influence of the sulphur and magnesium content on donor-acceptor-pair emission in nitrogen-plasma doped ternary and quaternary ZnMgSSe", talk, B. Jobst, S. Strauf, P. Baeume, E. Kurtz, H. Schenk, J. Gutowski, D. Hommel, and G. Landwehr,

   

  Proc. of Int. Symposium on Blue Laser (ISBLED), Chiba, Japan, Ohmsha Ltd. (1996), p. 409.

Project Description

The optical emission of single wall carbon nanotubes (SWCNTs) is governed by bright exciton emission similar to self-assembled quantum dots (QDs). In contrast to self-assembled QDs, SWCNT emit efficiently at RT and their emission wavelength can be easily tuned to telecom wavelength by tuning their diameter in the CVD growth process. One goal is to explore the exciton photophysics of individual SWCNT and to come up with new ways to realize efficient quantum light sources, in particular single photon sources. Blinking and spectral diffusion are hallmarks of quantum emitters and generally considered as detrimental properties for devices applications. We have shown for the first time that the often observed quantum intermittency (blinking) and spectral diffusion effects are extrinsic phenomena and we demonstrated how to eliminate these detrimental effects by embedding SWCNTs into polymer cavities. Very recently we also demonstrated photon antibunching and prolonged exciton dephasing times, which are both promising properties towards on-chip quantum photonics. The Figure shows a recent demonstration of quantum optical signatures from individual cavity-embedded SWCNTs. The cavity device achieve about 50-fold enhanced exciton emission as compared to bare SWCNT while effectively suppressing detrimental quantum blinking. “Quantum light sources based on individual carbon nanotubes”, W. Walden-Newman and S. Strauf, book chapter, to appear in “Carbon nanotubes and graphene for photonic applications”, Woodhead Publishing (2012). „Quantum Light Signatures and Nanosecond Spectral Diffusion from Cavity-Embedded Carbon Nanotubes“ W. Walden-Newman, I. Sarpkaya, and S. Strauf, Nano Letters 12, 1934 (2012). “Suppression of Blinking and Enhanced Light Emission from Individual Carbon Nanotubes“, N. Ai, W. Walden-Newman, Q. Song, S. Kalliakos, and S. Strauf, ACS Nano 5, 2664 (2011).

Project Description

Holographic lithography (HL) is a versatile tool to fabricate large-scale periodic structures with high throughput at submicron scale such as photonic crystals and nanoplasmonic arrays. Standard two-beam interference is rather limited in the type of lattice and motive shape. In contrast, one can realize almost arbitrary motive shapes based on four-beam HL. In particular, we have demonstrated that feature sizes down to 20 nm can be reliably achieved based on exposure at 488 nm, i.e. 24 times smaller than the laser wavelength. The key to achieve nanoantenna arrays with 20 nm feature size and controlled motive shape (e.g. sharp tips, field orientation) is the introduction of the fourth beam in HL which splits the local motive shape into a double-peaked feature (twin motive or compound lattice), as shown in the Figure. It is this inner gap of the twin motive in the interference pattern itself that can be tuned down to sub-20 nm, or even to zero, by proper control of phase and polarization. We have fabricated nanoplasmonic templates first in polymer (Hole pattern in SU8), which were transformed into plasmonic nanogap arrays (twin-dot pattern) by metal deposition and stripping of the polymer template. Recently we have also been able to fabricate plasmonic arrays with triplet and quadruplet features and controlled field orientation, significantly enlarging the utility of HL. Currently we study the light-matter interaction of the plasmonic nanogap arrays seeking applications in SERS and characterization of graphene.

"Formation of triplet and quadruplet plasmonic nanoarray templates by holographic lithography," X. Zhang and S. Strauf, submitted (2012)

"Holographic Control of Motive Shape in Plasmonic Nanogap Arrays," X. Zhang, M. Theuring, Q. Song, W. Mao, M. Begliarbekov, and S. Strauf, Nano Letters 11, 2715 (2011).

Project Description

Quantum information science is a fast growing and highly interdisciplinary field with the potential to cause revolutionary advances in science and engineering. Semiconductor cavity quantum electrodynamics systems provide an a priori scalable platform for quantum optics experiments and allow the development of quantum photonic devices for applications in quantum information science. The objective is to demonstrate deterministic coupling of lithographically defined vertical quantum dots to photonic crystal resonators for the realization of scalable quantum photonic devices. The proposed research program aims to utilize a novel type of lithographically defined "vertical QD" etched from a 2DEG wafer which is optically active and can be precisely tuned and positioned by electron beam lithography with respect to a PC cavity mode (picture), thereby eliminating the problem of random nucleation inherent to self-assembled QDs. Quantum dots and cavities can be combined with waveguides and beam splitters in a large number on a photonic crystal platform. Since the QDs are created by etching the randomness of self-assembled growth is eliminated, paving the way for scalability.

Project Description

The goal of this project is to fabricate single electron transistors (SET) from single walled carbon nanotubes operating at elevated temperatures. The approach is to fabricate nanosegments along the nanotube effectively creating a CNT quantum dot with large charging energy AND large level spacing. As a first step, we have fabricated field-effect transistor (FET) structures using CNTs as the conducting channel by using chemical vapor deposition to achieve in-plane growth from catalyst tips (Figure a). Devices have an initial on/off ratio of about two in the transfer characteristic due to contribution of metallic tubes. After controlled electrical breakdown only semiconducting tubes remain and we achieve on/off ratios of semiconducting p-FETs with individual SWCNTs as high as 105 at room temperature and without top gating. At low temperatures devices display pronounced peaks in the conductivity caused by the Coulomb blockade effect demonstrating SET operation (Figure d). Segmentation along the SWCNTs can be achieved wit local anodic oxidation (Bottom figures).

"A Study on Nanoscale Carbon Nanotube Local Oxidation Lithography using an Atomic Force Microscope", K. Kumar, O. Sul, S. Strauf, F. Fisher, D. S. Choi, M. G. Prasad, and E. H. Yang, IEEE Trans. Nanotechnology 99, 1 (2011).

"Transconductance and Coulomb blockade properties of in-plane grown carbon nanotube field effect transistors", N. Ai, O. Sul, M. Begliarbekov, Q. Song, K. Kumar, D. S. Choi, E. H. Yang, S. Strauf, Nanosci. Nanotechnol. Lett. 2, 73-78 (2010).

"A Systematic Study of Graphite Local Oxidation Lithography Parameters Using an Atomic Force Microscope", K. Kumar, S. Strauf, and E.H. Yang, Nanosci. Nanotechnol. Lett. 2, 185-188 (2010).

Project Description

In contrast to most conventional materials, in which charge transport is governed by the Schrodinger equation, charge transport in graphene obeys the Dirac equation. Consequently, the charge carrying particles are chiral Dirac fermions. This makes graphene the ideal test material for quantum electrodynamic (QED) phenomena of electrons – a regime of physics which was previously inaccessible in solid-state systems. This promises a similar degree of quantum control of electrons as compared to what is now well established in cavity-QED with photons. The goal of this project is to study the quantum transport properties in top-gated graphene filed-effect transistors and to assess their applicability to the design of nanoelectronics devices. We have recently constructed such a FET with a 100 nm top gate which defines a local tunnel barrier. Carrier transport through this barrier reveals aperiodically spaced conductivity oscillations. Besides the well known magnetic field effect, these conductance oscillations can be taken as another signature of Klein-tunneling in graphitic nanostructures.

“Quantum Inductance and High Frequency Oscillators in Graphene Nanoribbons“, M. Begliarbekov, S. Strauf, and C.P. Search, Nanotechnology 11, 165203 (2011).

"Aperiodic conductivity oscillations in quasi-ballistic graphene heterojunctions", M. Begliarbekov, O. Sul, N. Ai, E. H. Yang, S. Strauf, Appl. Phys. Lett. 97, 122106 (2010).

Na Liu, Ph.D. candidate since 2018

Research: Quantum photonics based on lithium niobate

Xiaowei He, Postdoctoral Researcher

Research: Quantum light sources based on carbon nanotubes

Yichen Ma, Ph.D. candidate since 2016

Research: 2D Nanolaser arrays in TMDCs

Kamran Shayan, Ph.D. candidate since 2014

 Research: Cavity QED with doped SWCNTs

Xiangzhi Li,  Ph.D. candidate since 2014

 Research: Practical quantum light sources based on boron nitride

Yue Luo (Leroy), Ph.D. candidate since 2013

Ph.D. candidate since 2013

Dr. Gabriella D. Shepard, Ph.D. May 2018

Thesis: Optical Properties of 2D and 0D Excitons in Atomically Thin Semiconductors

Dr. Ibrahim Sarpkaya, Ph.D. July 2015

Thesis: "Controlling Exciton Photophysics in Carbon Nanotubes"

Dr. Ehsaneh D. Ahmadi, Postdoctoral Researcher 2014/2015

Research: Controlling exciton-phonon coupling in carbon nanotubes

Dr. Xi Zhang, Ph.D. June 2013

Thesis: "Holographic Lithography for Plasmonics"

Dr. Will Walden-Newman, Ph.D. May 2012

Thesis: "Carbon Nanotubes as non-classical light source in quantum photonics"

Dr. Milan Begliarbekov, Ph.D. Dec. 2011

Thesis: "Physics at the Edge of Graphene"

Dr. Nan Ai, Ph.D. Nov. 2010

Thesis: "Individual Carbon Nanotubes for Quantum Electronics and Quantum Photonic Devices"

Dr. Sokratis Kalliakos, Research Assistant Professor 2009/2010

Research: Vertical quantum dots coupled to photonic crystal nanocavities

Dr. Weidong Mao, Research Assistant Professor 6/2008 - 6/2009

Research: Fabrication of compound photonic crystals by holographic lithography