Bachelorstudium in Wirtschaftsingenieurwesen Elektrotechnik und Informationstechnik

Semiconductor Epitaxy Group

Prof. Dr. habil. Detlef Hommel

 

University of Bremen
Institute of Solid State Physics
- Semiconductor Epitaxy -
Otto-Hahn-Allee NW1
D-28359 Bremen
+49-421-218-62220

hommel(at)ifp.uni-bremen.de

 

Scientific degrees and titles:

• 1975 MSc – Physics Dept. University of Warsaw (Poland)
• 1979 PhD – Physics Dept. University of Warsaw
• 1989 Habilitation (Dr. sc. nat.) - Humboldt-University Berlin
• 1991 Dr. habil. rer. nat. – University Leipzig
• 1993 Privatdozent – University Würzburg
• 1994 University Professor (C4) – University of Bremen

 

Employment:

• 1979-91 Central Institute of Electron Physics, Academy of Science, Berlin
• 1991-94 Würzburg University, Dept. Exp. Physics III
• 1994 - University of Bremen, Faculty of Physics and Electrical Engineering,
  Head of Semiconductor Epitaxy


Scientific field of interest:

Condensed matter physics, mainly semiconductors and optoelectronic devices: spectroscopy
of Rare Earth ions in wide gap materials; thin film electroluminescence; modern technologies
especially for semiconductor epitaxy (molecular beam epitaxy MBE and metal organic
vapour phase epitaxy MOVPE) and processing (focused ion beam, photo- and e-beamlithography,
various deposition methods); nanoscience (quantum dots, micropillars and
nanorods); structural, electrical and optical characterization of heterostructures;
optoelectronic devices (laser diodes, surface emitters, single photon sources, sensors); basic
properties of wide bandgap semiconductors (group-III nitrides, II-VI selenides and tellurides)

 

Scientific output and science guidance experiences:

• 538 original publications in internationally cited journals, among them Nature and
  Nature Physics, 6 Phys. Rev. Letters, 48 Phys. Rev. B, 3 Electronic Letters, 47 Appl.
  Phys. Letters, 22 J. Appl. Phys.; above 5,500 citations;
• Hirsch index 33;
• 30+ invited talks at major international condensed matter conferences;
• 20 PhD and 35+ MSc theses supervisor; out of the group one female professor at University of Aachen;

• evaluator of physics theses in Tampere and Helsinki and Warsaw;


Major accomplishments in research and education management:

• Teaching of basic lectures as well as on specialized topics for physicists and
  electrical engineers at the universities of Würzburg, Bremen, UC Santa Barbara and
  Warsaw, Wroclaw (in German, English and Polish)
• Build up of the Semiconductor Epitaxy Laboraty at University of Bremen including
  twin MBE-chamber (II-VI and III-V) plus XPS chamber, MOVPE, HRXRD at variable
  temperatures, dual focused ion beam with e-beam-lithography, AFM, CAIBE for dry
  etching, equipment for electrical and optical measurements;
• 2003-09 Speaker of the DFG Research Group “Physics of nitride-based, nanostructured, light-emitting devices”
• 2008-11 Vice-speaker of the Virtual Institute “PINCH-Photonics” in frame of the Helmholtz-Society at Research Center (FZ) Karlsruhe
• Research grants by DFG, BMBF, Helmholtz-Society, Volkswagen Foundation and Bremen State with a total value of about 8 mln €
• Visiting professor at the University of Wroclaw, Poland

 

Patents:

10 patents on semiconductor devices including those for:

• White LEDs based on ZnSe (US 09/915,985; DE 199 02 750)
• Contact design for II-VI laser diodes (US 09/787,186), DE 198 42 212)
• Low ohmic contacts to p-GaN (DE 1999E08234),
• Method for nitrides and selenides wafer bonding (UC 2004-455, with UCSB, USA)
• InGaN quantum dots (DE 10 2005 057 253)
• Te-based monolithic DBR lattice matched to ZnTe (Europ. patent appl. 09151148.5)

 

Major internationally recognized achievements:

1993 Green ZnSe laser diode (LD)
1998 Homoepitaxial ZnSe LD on ZnSe substrate in cw-operation
1999 Distributed Feedback (DFB) laser (II-VI) in the green spectral region
2000 Laser diode emitting at 560 nm (yellow-green) *
2001 Quantum dot LD with CdSe/ZnSSe *
2002 First European university realizing a violet nitride-based laser diode
2004 Homoepitaxial laser diode emitting at 400 nm on a GaN-HVPE substrate
2005 cw-operation of a GaN laser diode as first university worldwide
2008 Self organized, mask-free GaN nanorods on r-plane sapphire
2011 Antibunching at room temperature for CdSe/ZnSSe/MgS quantum dots *
(* first worldwide)

 

International collaboration partners:

• UC Santa Barbara, USA (Profs. S. Nakamura, S. DenBaars, J. Speck)
• Linköping University, Sweden (Profs. Bo Monemar, E. Janzen)
• University of Warsaw, Poland (Profs. M. Grynberg, J. Gaj, J. Baranowski)
• Institute of Physics PAS, Warsaw, Poland (Profs. M. Godlewski, G. Karczewski)
• Bath University, UK (Prof. J. Davies)
• Ritsumeikan University, Japan (Prof. Y. Nanishi)
• Mejo University, Japan (Profs. I. Akasaki, H. Amano)
• Chiba University (Prof. A. Yoshikawa)
• University of Cincinnaty, USA (Prof. H.-P. Wagner)
• CEA & CNRS Grenoble, France (Profs. H. Mariette, Le Si Dang)
• ELLETRA Trieste, Italy (Prof. A. Franciosi)

 

Major international scientific conferences as organizer or co-chair:

1994 Chairman “International Workshop on Blue Lasers” in Würzburg
1996 Co-chairman “German-Japanese Workshop on II-VI Compounds” in Bremen
2001 Co-chairman “10th International Conference on II-VI Compounds” in Bremen
2005 Chairman “6th International Conference on Nitride Semiconducturs” in Bremen
2008 Co-organizer E-MRS Strasbourg, Symposium G “Wide bandgap”
2009 Co-organizer E-MRS Fall Meeting Warsaw, Symposium “Wide bandgap”
2012 Co-chairman “International Symposium on Light Emitting Structures” in Berlin

 
Member of International Advisory Committees in the following series:

• International Symposium on Light Emitting Structures (1998 – 1970)
• International Conference on II-VI Compounds (since 1997)
• International Conference on Nitride Semiconductors (since 2009)
• International Workshop on Nitride Semiconductors (since 2004)
• International Symposium on the Growth of Nitrides (since 2008)

 

Member of International Programme Committees (>15)

Scientific awards and activities abroad:
1997 Visiting Professor at Yamaguchi University, Japan (3 month)
1998 Distinguished Guest at QUEST, University of Santa Barbara (2 month)
2000 Visiting Professor at Chiba University, Japan (3 month)
2006 - 2009 Alexander von Humboldt Honorary Research Fellowship of the Polish Science Foundation FNP (12 month over a 3 year period) in Warsaw
2010 - Scientific Coordinator of the Wroclaw Research Center EIT+, Poland
2011 - Visiting Professor at University of Wroclaw, Poland (two month per year)

 

Selected publications:

 
Direct observation of correlations between individual photon emission events of a microcavity laser
 
J. Wiersig, C. Gies, F. Jahnke, M. Aßmann, T. Berstermann, M. Bayer, C. Kirstner, S. Reitzgenstein,
C. Schneider, S. Höfling, A. Forchel, C. Kruse, J. Kalden, and D. Hommel
Nature 460 (2009) 245
 
Highly ordered catalyst-free and mask-free GaN nanorods on r-plane sapphire
 
T. Aschenbrenner, C. Kruse, G. Kunert, S. Figge, K. Sebald, J. Kalden, T. Voss, J. Gutowski, and
D. Hommel
Nanotechn. 20 (2009) 075604
 
High-reflectivity broadband distributed Bragg reflector lattice matched to ZnTe
 
W. Pacuski, C. Kruse, S. Figge, and D. Hommel
Appl. Phys. Lett. 94 (2009) 191108
 
Electrically driven single quantum dot emitter operating at room temperature
 
R. Arians, A. Gust, T. Kümmell, C, Kruse, S. Zaitsev, G. Bacher, and D. Hommel
Appl. Phys. Lett. 93 (2008) 173506

 
Green laser emission from monolithic II-VI-based pillar microcavities near room temperature
 
C. Kruse, H. Lohmeyer, K. Sebald, J. Gutowski, D. Hommel, J. Wiersig, and F. Jahnke
Appl. Phys. Lett. 92 (2008) 031101

 
Superradiance of quantum dots
 
M. Scheibner, T. Schmidt, L. Worschech, A. Forchel, G. Bacher, T. Passow, and D. Hommel
Nature Physics 3 (2007) 106

 
Enhanced spontaneous emission of CdSe quantum dots in monolithic II-VI pillar microcavities
 
H. Lohmeyer, C. Kruse, K. Sebald, J. Gutowski and D. Hommel
Appl. Phys. Lett. (2006) 91107

 
Temperature dependence of the thermal expansion of GaN
 
C. Roder, S. Einfeldt, S. Figge, and D. Hommel
Phys. Rev. B 72 (2005) 85218

 
Resonant modes in monolithic nitride pillar microcavities
 
H. Lohmeyer, K. Sebald, J. Gutowski, R. Kröger, C. Kruse, D. Hommel, J. Wiersig, and F. Jahnke
Eur. Phys. J. B 48 (2005) 291

 
Optical properties of epitaxially grown sub-momolayer CdSe/ZnSe nanostructutres
 
A.M. Kapitonov, T. Itoh, U. Woggon, D. Kayser, and D. Hommel
Phys. Rev. B 70 (2004) 195304

 
Wafer bonding of GaN and ZnSSe for optoelectronic applications
 
A. Murai, L. McCarthy, U. Mishra, S.P. DenBaars, C. Kruse, S. Figge, and D. Hommel
Jpn. J. Appl. Phys. 10A (2004) L1275

 
Direct observation of optically injected spin-polarized currents in semiconductors
 
J. Hübner, W.W. Rühle, M. Klude, D. Hommel, R.D.R. Bhat, J.E. Sipe, and H.M. van Driel
Phys. Rev. Lett. 90 (2003) 216601

 
Quantum optical studies on individual acceptor bound exciton in a semiconductor
 
S. Strauf, P. Michler, M. Klude, D. Hommel, G. Bacher, and A. Forchel
Phys. Rev. Lett. 89 (2002) 177403

 
Single photon emission of CdSe quantum dots at temperatures up to 200 K
 
J. Sebald, P. Michler, T. Passow, D. Hommel, G. Bacher, and A. Forchel
Appl. Phys. Lett. 81 (2002) 2920

 
Quantum dot formation by segregation enhanced CdSe reorganisation
 
T. Passow, K. Leonardi, H. Heinke, D. Hommel, D. Litvinov, A. Rosenauer, D. Gerthsen, J. Seufert, G.
Bacher, and A. Forchel
J. Appl. Phys. 92 (2002) 6546
 
Electrically pumped lasing from CdSe quantum dots
 
M. Klude, T. Passow, R. Kröger, and D. Hommel
Electr. Lett. 37 (2001) 1119
 
560-nm-continuous wave laser emission from ZnSe-based laser diodes on GaAs
 
M. Klude, and D. Hommel
Appl. Phys. Lett. 79 (2001) 2523
 
In as a surfactant for the growth of GaN (0001) by plasma-assisted molecular-beam epitaxy
 
C. Kruse, S. Einfeldt, T. Böttcher, and D. Hommel
Appl. Phys. Lett. 79 (2001) 3425
 
The role of high-temperature island coalescence in the development of stresses in GaN films
 
T. Böttcher, S. Einfeldt, S. Figge, R. Chierchia, H. Heinke, D. Hommel, and J.S. Speck
Appl. Phys. Lett. 78 (2001) 1976
 
X-ray diffraction analysis of the defect structure in epitaxial GaN
 
H. Heinke, V. Kirchner, S. Einfeldt, and D. Hommel
Appl. Phys. Lett. 77 (2000) 2145
 
In situ and ex situ evaluation of the film coalescence of GaN grown on GaN nucleation layer
 
S. Figge, T. Böttcher, S. Einfeldt, and D. Hommel
J. Cryst. Growth 221 (2000) 262
 
Fine structure of biexciton emission in symmetric and asymmetric CdSe/ZnSe single quantum
dots

D. Kulakovskii, G. Bacher, R. Weigand, T. Kümmell, A. Forchel, E. Borovitskaya, K. Leonardi, and
D. Hommel
Phys. Rev. Lett. 82 (1999) 1780
 
Planar homoepitaxial laser diodes grown on aluminium-doped ZnSe substrates

H. Wenisch, K. Ohkawa, A. Isemann, M. Fehrer, and D. Hommel
Electr. Lett. 34 (1998) 891

 
Ion-induced crystal damage during plasma-assisted MBE growth of GaN layers
 
V. Kirchner, H. Heinke, U. Birkle, S. Einfeldt, D. Hommel, H. Selke, and P.L. Ryder
Phys. Rev. B 58 (1998) 15749

 
CdSe/ZnSe quantum structures grown by migration enhanced epitaxy: structural and optical
investigations

 
K. Leonardi, H. Heinke, K. Ohkawa, D. Hommel, H. Selke, F. Gindele, and U. Woggon
Appl. Phys. Lett. 71 (1997) 1510

 
First order gain coupled DFB lasers in ZnSe-based structures with finely tunable emission
wavelengths

D. Eisert, G. Bacher, N. Mais, J.P. Reithmaier, A. Forchel, B. Jobst, D. Hommel, and G. Landwehr
Appl. Phys. Lett. 68 (1996) 599

 
Blau-grün emittierende ZnSe Laserdioden
 
G. Landwehr and D. Hommel
Physikalische Blätter 50, Heft 2, (1994), 160

 
Chlorine: a new efficient n-type dopant in CdTe layers grown by molecular beam epitaxy
 
D. Hommel, A. Waag, S. Scholl, and G. Landwehr
Appl. Phys. Lett. 61 (1992), 1546

 
Thermoluminescence mechanism in CdF2 :Eu
 
H. Przybylinska, M. Godlewski, and D. Hommel
Phys. Rev. B 46 (1992), 7395

 
Recombination processes in ZnS: Sm
 
K. Swiatek, M. Godlewski, and D. Hommel
Phys. Rev. B 43 (1991), 9955

 
Deep europium-bound exciton in a ZnS lattice
 
K. Swiatek, M. Godlewski and D. Hommel
Phys. Rev.B 42 (1990), 3628

 
Nature of the charge transfer states of the trigonal and tetragonal Eu3+ centers in CdF2 crystals
 
D. Hommel, and J.M. Langer
J. Lumin. 18/19 (1979), 281