Semiconductor Quantum Nanomaterials

The Semiconductor Quantum Nanomaterials group provides a broad array of research activities in advanced epitaxial heterostructures and nanostructures, the characterization of their structural, electronic, optical and thermal properties, and their functionalization in nanoscale device applications. We conduct collaborative, integrated and multidisciplinary research on a wide range of III-V semiconductor compounds and topics, encompassing five major themes described below. Most of our work capitalizes on the superior electronic and optoelectronic properties of the arsenide and nitride materials, and exploitation of sophisticated effects at the nanoscale to test their performance in related devices. Large emphasis is placed on molecular beam epitaxial (MBE) growth of ultra–high mobility GaAs–based heterostructures, novel In(Ga,Al)As–based quantum dots and nanowires on silicon, (In,Ga,Al)N-based heterostructures for optoelectronic and thermoelectric applications, and unique in situ methods (cleaved edge overgrowth) for nanofabrication of sub-nanometer patterns for organic and molecular electronics. All of our work employs the recently established, advanced nanofabrication and characterization facilities at the Center for Nanotechnology and Nanomaterials (ZNN) at WSI.

Current Research Topics

 

 

Recent Publications

A list of recent publications can be found here

Previous Publications (Group Leader)

A list of all previous publications of the group leader can be foundhere

Group members

October 2016, from left to right: Damon Carrad, Thomas Stettner, Jakob Seidl, Gregor Koblmüller, Lin Han, Tobias Kostenbader, Anton Faustmann, Lukas Seidl, Daniel Ruhstorfer, Hubert Riedl, Bernhard Loitsch, Jonathan Becker, Jochen Bissinger, Marco Berger, Max Waldher

Group Leader

Gregor Koblmüller

Ph. D. Students

Jonathan Becker

Engineer

Hubert Riedl

Master

Lin Han

Interns

 

Alumni (PhD Students)

Kai Saller, Bernhard Loitsch, Julian Treu, Ben Mayer, Stefanie Morkötter, Simon Hertenberger, Daniel Rudolph

Alumni (Postdoctoral Researchers)

Damon Carrad

Alumni (Diploma/Master Students)

Banani Biswas, Macro Berger, Lukas Stampfer, Tobias Kostenbader, Max Sonner, Max Waldherr, Daniel Ruhstorfer, Philipp Zimmermann, Georg Haunschild, Dominik Irber, Alexander Hirler, Maximilian Speckbacher, Julia Winnerl, Xiaomo Xu, Lisa Janker, Gianluca Grimaldi, Martin Rutzinger, Andreas Brenneis, Kun Chen, Emanuel Forster, Philipp Geselbracht, Florian Herzog, Verena Hintermayr, Nicolas Hörmann, Mengyu Liang, Bernhard Loitsch, Tao Yang, Michael Bormann, Pascal Witlich, James Zi-Jian Ju

 

Funding

Funding by the following agencies is gratefully acknowledged

  • ERC Consolidator Grant
  • Deutsche Forschungsgemeinschaft (DFG-Sonderforschungsbereich SFB 631)
  • International Graduate School of Science & Engineering (IGSSE-TUM)
  • Deutsche Forschungsgemeinschaft (DFG-Individual Research Grants)
  • Nanosystems Initiative Munich (NIM)
  • Marie Curie Actions – FP7–People – International Reintegration Grant (IRG)
  • Bavaria California Technology Center
  • EU FP7 project SOLID
  • IBM University Programs World-wide
TUM Technische Universität München TUM Technische Universität München Physik Department Elektrotechnik und Informationstechnik TUM Technische Universität München
 

Contact

Dr. Gregor Koblmüller Tel :: +49 89 289 12779 Office :: S315 Email :: gregor.koblmueller@wsi.tum.de

Recent Highlights

D. Irber, et al.: “Quantum transport and subband structure of modulation-doped GaAs/AlAs core-superlattice nanowires ”, Nano Lett. 17, 4886 (2017).

A. V. Bubis, et al.: “Proximity effect and interface transparency in Al/InAs-nanowire/Al diffusive junctions”, Semicond. Sci. Technol. 32, 094007 (2017).

I. Beleckaite, et al.: “Enhanced THz emission efficiency of composition-tunable InGaAs nanowire arrays”, Appl. Phys. Lett. 110, 201106 (2017).

B. Mayer, et al.: “Long-term mutual phase locking of picosecond pulse pairs generated by a semiconductor nanowire laser”, Nature Comm. 8, 15521 (2017).

G. Koblmüller, et al.: “GaAs-AlGaAs core-shell nanowire lasers on silicon: Invited review”, Semicond. Sci. Technol. 32, 053001 (2017).

T. Stettner, et al.: “Direct coupling of coherent emission from site-selectively grown III-V nanowire lasers into proximal silicon waveguides”, ACS Photonics 4, 2537 (2017).

B. Loitsch, et al.:“Suppression of alloy fluctuations in GaAs-AlGaAs core-shell nanowires”, Appl. Phys. Lett. 109, 093105 (2016).

M. Speckbacher, et al.: “Direct measurements of Fermi level pinning at the surface of intrinsically n-type InGaAs nanowires”, Nano Lett. 16, 5135 (2016).

B. Loitsch, et al.: “Microscopic nature of crystal phase quantum dots in ultrathin GaAs nanowires”, New J. Phys. 18, 063009 (2016).

J. Ju, et al.: “Thermoelectric properties of In-rich InGaN and InN/InGaN superlattices”, AIP Advances 6, 045216 (2016).

B. Mayer, et al.: “Continuous wave lasing of individual GaAs-AlGaAs core-shell nanowires”, Appl. Phys. Lett. 108, 071107 (2016).

J. Treu, et al.: “Widely tunable alloy composition and crystal structure in catalyst-free InGaAs nanowire arrays grown by selective area molecular beam epitaxy”, Appl. Phys. Lett. 108, 053110 (2016).

T. Stettner, et al.: “Coaxial GaAs-AlGaAs core-multishell nanowire lasers with epitaxial gain control”, Appl. Phys. Lett. 108, 011108 (2016).

B. Mayer, et al.: “Monolithically integrated high-β nanowire lasers on silicon”, Nano Letters 16, 152 (2016).

Upcoming Events (2017/2018)

01/27 – 09/02
SPIE Photonics West 2018, San Francisco, U.S.A.
Gregor Koblmüller – Invited Talk, Jochen Bissinger, Tom Stettner – Contributed Talks
10/30 – 10/31
CENTRANS Workshop, FUNSOM, Soochow University, Suzhou, China
Gregor Koblmüller – Invited Talk
08/28 – 09/02
IUMRS-ICAM 2017, 15th Intl. Conference on Advanced Materials, Kyoto, Japan
Gregor Koblmüller – Contributed Talk
 08/20 – 08/24
24th Congress of the International Commission for Optics (ICO-24), Tokyo, Japan
Gregor Koblmüller – Invited Talk
06/20 – 06/23
Materials Engineering Seminar, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
Gregor Koblmüller – Invited Talk
05/29 – 06/02
Nanowire Week 2017, Lund University, Lund, Sweden
Jonathan Becker, Jochen Bissinger, Gregor Koblmüller, Daniel Ruhstorfer, Thomas Stettner – Oral and Poster Presentations
05/15 – 05/19
44th Int’l Symposium on Compound Semiconductors (CSW-ISCS-2017), Berlin, Germany
Gregor Koblmüller – Contributed Talks
04/05
Physics & Materials Science Research Unit, University of Luxembourg, Luxembourg
Gregor Koblmüller – Colloquium
03/20 – 03/24
DPG Frühjahrstagung, Dresden, Germany
Jonathan Becker, Jochen Bissinger, Tobias Kostenbader, Franz Langrieger, Lukas Stampfer – Oral Presentations
03/16
Clustermeeting „Nano-Patenting“, Nanoinitiative Bayern GmbH, Garching, Germany
Gregor Koblmüller – Invited Talk
02/15
DFG-Graduate School Seminar “Functionalization of Semiconductors”, Philipps-University Marburg, Marburg, Germany
Gregor Koblmüller – Invited Talk
01/27 – 02/02
SPIE Photonics West 2017, San Francisco, U.S. A.
Gregor Koblmüller – Invited Talk