CURRICULUM
VITAE
Tomasz Jan Ochalski was born 3rd
of September 1970 in Lublin, Poland. At present he is an adjunct in the
Institute of Electron Technology (IET) in Warsaw. He works in Department
of Physics and Technology of Low Dimensional Structures and he is a head of
Laboratory of Optical Spectroscopy in this department. The
Institute of Electron Technology is a major Polish research centre with the
primary focus on semiconductor micro- and nanotechnology.
Information about institute can be found at http://www.ite.waw.pl/.
High school and Master
of Science degree
In 1989 Tomasz J.
Ochalski finished high school with extended mathematics and physics. In the
same year he started his study at the Institute of Physics at Maria
Curie-Sklodowska University in Lublin. He achieved M.Sc. in physics in 1994
and title of the thesis was “Ionoluminescence of the oxidized porous
silicon”. The main part of the M.Sc. work was published (list of
publications nr. 2).
Doctorate
In 1994 he started Ph.D. study at his home Institute
of Physics in the field of solid state physics. In 1997 he started to cooperate
with the Institute of Electron Technology and for the next three years his
activity was divided between these two institutes. Finally he realized two
parallel projects and this resulted in two different Ph.D. thesis. He
achieved doctorate in technical science and doctorate in physics almost at the
same time in 2001. Ph.D. thesis accomplished in Institute of Electron
Technology was entitled “High spatially resolved optical spectroscopy of the
optoelectronic device structures” (September 2001) and the title of thesis
correlated to Maria Curie-Sklodowska University was “Photoreflectance
spectroscopy of semiconductor compounds” (December 2001). The first
thesis was written on the basis of publications nr. 6, 7, 12, 14 and the second
one on publications 1, 3, 4, 5.
In both cases external
reviewers proposed distinction of the thesis.
Tomasz Ochalski started his own first real
experiment during M.Sc. studies. He performed a number of optical experiments
using high energy proton and oxygen ion beams. After short training he
operated 300 keV implanter combined with mass separator. The young scientist
was brave enough to maintain giant separator alone and finished his ambitious
M.Sc. thesis on time.
During his first year of Ph.D. studies he was
involved in building mass separator-implanter and cyclotron tandem. He was
the chief of the team which projected and actuated computer-driven vacuum
system of whole tandem. These facts emphasise his independent thinking and
leadership ability.
After cyclotron startup he completely devoted
himself to solid state physics and particularly to optical properties of
semiconductor compounds. During Ph.D. studies he built and develop
photoreflectance spectrometer which was a main instrument in his
experiments at Maria Curie-Sklodowska University. On his spectrometer he
examined influences of epitaxial layer thickness on built-in electric field in
region of GaAlAs/SI‑GaAs interface which has crucial role in field effect
transistors structures.
In 1998 Tomasz Ochalski achieved TEMPUS
Individual Mobility Grant (IMG). IMG allowed him to visit two laboratories
at the University of Surrey, GB and Universite Montpellier II, France, both
visits were two months long.
In
Montpellier he built the second photoreflectance spectrometer, UV enhanced.
At that time the dependence of the AlGaN band gap with alloy
composition was not very
well known, he investigated the bowing parameter in AlGaN
alloys lattice-matched to GaN and this short visit yielded publications nr 4 and 5. This two
publications were cited 30 times.
In Surrey he was rather observer and the main
topic of observed experiments was modulation spectroscopy of vertical cavity
surface emitting lasers (VCSEL). It was described in “Photomodulated
reflectance study of InxGa1-xAs/GaAs/AlAs
microcavity vertical-cavity surface emitting laser structures in the
weak-coupling regime: The cavity/ground-state-exciton resonance”, P. J. Klar,
G. Rowland, P. J. S. Thomas, A. Onischenko, T. E. Sale, and T. J. C. Hosea*,
Phys. Rev. B 59, 2894 (1999).
After this visit he was involved in Polish
Committee for Scientific Research grant for creating first polish VSCEL. During
this project he started to create his own optical group specialized in
photoluminescence (PL), photoluminescence excitation (PLE), electro and
photoreflectance, thermoreflectance and finally in micro-Raman spectroscopy. In
this project the group designed and developed prototype series of resonant
cavity LEDs and VCSELs
In 2000 he achieved grant funded by Linkoping
University, Sweden. In Sweden he obtained skill and experience in time
resolved spectroscopy. The big achievement in Linkoping was obtaining
optically induced laser emission from polish VCSEL, this was the milestone in
development electrically pumped VCSEL. Time resolved photoluminescence (TRPL)
is one of the main interests of Tomasz Ochalski. Due to lack of expensive RTPL
setup in Warsaw he visited Linkoping University and Max Born Institute in
Berlin number of times and perform there experiments concerning dynamics of PL.
In 2002 he started 24 months long post doctoral
fellowship in The Nederlands at University of Nijmegen. His main subject in
Nijmegen was optical characterization of transistor structures based on nitride
alloys grown on sapphire and silicon carbide. He was also involved to the
project about photosensitive tips to the scanning tunneling microscopy (STM).
Since the beginning of 2004 Tomasz Ochalski is a head of
Laboratory of Optical Spectroscopy in IET, Warsaw. He is liable for three Ph.D.
students and with cooperation with Technical University of Warsaw one M.Sc.
student.
Description of the lab
you can find on http://www.ochalski.com
Tomasz Ochalski was involved in
national and European grants:
·
Semiconductor Microcavities: Technology, Physical
Properties and Applications in Optoelectronic, State Committee for Scientific
Research, contract 8T 11B 02018.
·
Study of facet heating and degradation mechanisms in
etchet facet lasers, Fifth Framework Programme, IST-1999- 10787-E.
·
High Power High Electron Mobility Transistors based on
AlGaN/GaN structure. Dutch Technical Foundation (STW).
·
Spatially resolved thermoreflectance study of
degradation mechanism of high power laser diode mirrors, State Committee for
Scientific Research, contract 3T 11B 03128.
His main publications were cited in last years more than thirteen times.
Publications:
1.
T.J. Ochalski, J.
Żuk, L.A. Vlasukova, Effect of epitaxial
layer thickness on built-in electric field in region of GaAlAs/SI‑GaAs
interface: a photoreflectance study, Acta Physica Polonica 92, 935 (1997)
2.
J. Zuk, T.J. Ochalski, M. Kulik, J.
Liskiewicz, A.P. Kobzev, Efect of oxygen implantation on ionoluminescence of
porus silicon, Journal of Luminescence 80, 935 (1997)
3.
T.J. Ochalski, J.
Żuk, K. Regiński, M. Bugajski, Photoreflectance
studies of InGaAs/GaAs/AlGaAs single quantum well laser structures, Acta
Physica Polonica A 94, 463 (1998)
4.
T.J. Ochalski, B.
Gil, P. Lefebvre, N. Grandjean, M. Leroux, J. Massies, S. Nakamura, H. Morkoç, Photoreflectance investigation of the bowing
parameter in AlGaN alloys latice-matched to GaN, Applied Physics Letters 74, 3353 (1999)
5.
T.J. Ochalski, B.
Gil, P. Lefebvre, N. Grandjean, J. Massies, M. Leroux, Photoreflectance spectroscopy investigation of GaN-AlGaN quantum well
structures, Physica Status Solidi (b) 216,
221 (1999)
6.
T.J. Ochalski; J. Muszalski; M.
Zbroszczyk; J.M. Kubica; K. Regiński; J. Katcki; M. Bugajski, Spontaneous
Emission Control in InGaAs/GaAs Planar Microcavities with DBR Reflectors,
Optical Properties of Semiconductor Nanostructures, ed. M. Sadowski, NATO
Advanced Study, Institute Series, Plenum Press 2000 pp.201-210.
7.
K. Reginski, J. Muszalski, M. Bugajski, T.J. Ochalski, J.M. Kubica,
M. Zbroszczyk, J. Katcki, J. Ratajczak, MBE growth of planar microcavities
with distributed brag reflectors, Thin Solid Films 367, 290 (2000)
8.
J. Katcki, J. Ratajczak, K. Reginski, T.J. Ochalski, M.
Bugajski, F. Phillipp, Transmission electron microscopy and
photoluminescence study of laser heterostructures, Proc. Of 3rd
Japanese-Polish Joint Seminar of Material Analysis, Zakopane, 2000 pp.69-72
9.
H. Teisseyre, T.J.
Ochalski, P. Perlin, T. Suski, M. Bugajski, W. Gebicki, The influence of
erbium on the physical properties of GaN crystals grown from Nsolution in Ga at
high pressure, High Presure Research 35, 18 (2000)
10. T.J. Ochalski, B Gil, P. Bigenwald, M. Bugajski, P. Lefebvre, T. Taliercio, N.
Grandjean, J. Massies, The dual contribution to the Stokes-shift in
InGaN-GaN quantum wells, Physica Status Solidi (b) 228, 111 (2001)
11. M. Bugajski, M. Mroziewicz, K. Reginski,
J. Muszalski, J.M. Kubica, M. Zbroszczyk, P. Sajewicz, T. Piwonski, A.
Jachymek, R. Rutkowski, T.J. Ochalski, A. Wojcik, E. Kowalczyk, Strained
layer SCH SQW InGaAs/GaAs lasers for 980 nm band, Opto-Electr. Rev. 9,
35 (2001)
12. A. Wojcik, T.J. Ochalski, J. Muszalski, E. Kowalczyk, K.
Goszczynski, M. Bugajski, Photoluminescence mapping
and angle-resolved photoluminescence of MBE-grown InGaAsyGaAs RC LED and VCSEL
structures, Thin Solid Films 412,
114 (2002)
13. M. Bugajski, J. Muszalski, T.J. Ochalski, J. Katcki, B.
Mroziewicz, Resonant Cavity Enhanced Photonic Cevices, Acta Physica Polonica
A 101, 105 (2002)
14. K. Reginski, T.J.
Ochalski, J. Muszalski, M. Bugajski, J.P. Bergman, P.O. Holtz, B. Monemar, Investigations
of optical properties of active regions in vertical cavity surface emmiting
lasers grown by MBE, Thin Sol. Films 412, 107 (2002)
15. E. Kaminska, A. Piotrowska, K. Golaszewska, A. Barcz, R. Kruszka, T.J.
Ochalski, J. Jasinski, Z. Liliental-Weber, Electrical Properties and
Microstructure of Transparent ZnO Contacts to GaN, Physica Status Solidi
(c) 0, 231 (2002)
16. J.Muszalski, M.Bugajski, T.J.Ochalski, B.Mroziewicz,
H.Wrzesińska, M.Górska, J.Kątcki, InGaAs Resonant-Cavity Light-Emitting
Diodes (RC LEDs). Proc. of SPIE, Laser Technology VII, 5230, 98
(2003)
17. A.Wójcik, T. Piwoński, T.J. Ochalski, E. Kowalczyk, M. Bugajski,
A. Grzegorczyk, L. Macht, S. Haffouz, P.K. Larsen, Photoreflectance Study of
GaN/AlGaN Structures. Physica Status Solidi (c) 0, 491 (2002)
18. A. Szerling, K. Kosiel, M. Płuska, T.J. Ochalski,
J. Ratajczak, Oval Defects in Crystals Grown by MBE Technique: Study and
Methods of Their Elimination, Electron Technology -
Journal Internet 36, 1 (2004)
19. T.J. Ochalski , A. Grzegorczyk, M.
Rudzinski, P.K. Larsen, E. Kowalczyk, P.O. Holtz, P. Bergman, P.P. Paskov, Optical
study of AlGaN/GaN based HEMT structures, Phys. Stat. Sol. (c) 2,
2791 (2005)
20. T.J. Ochalski, T. Piwoński, D. Wawer, K.
Pierściński, M. Bugajski, A. Kozłowska, A. Malag, J. Tomm, Thermoreflectance
and micro-Raman measurements of the temperature distributions in broad contact
laser diodes, Optica
Applicata, 35, 3 (2005)
21. T.J. Ochalski , A. Grzegorczyk, M. Rudzinski,
P.K. Larsen, P.O. Holtz, P. Bergman P.P. Paskov, Optical study of AlGaN/GaN
based HEMT structures grown on sapphire and SiC,
phys. stat. sol. (a) 202, 1300 (2005)
22. K. Pierscinski , T.J. Ochalski, M. Bugajski, An analysis of
mounting strain in semiconductor structures by means of spatially resolved
optical modulation techniquees, Optica Applicata 35, 0 (2005)
23. D. Wawer, T.J. Ochalski, T. Piwoński, A. Wojcik-Jedlinska, M.
Bugajski, H. Page, Spatially resolved thermoreflectance study of facet
temperature in quantum cascade lasers, phys. stat. sol. (a) 202,
1227 (2005)
24. D. Wawer, T.J. Ochalski, T. Piwoński, M. Szymański, M. Bugajski,
Ł. Piskorski, K. Gutowski, A. Kozłowska, A. Maląg, Analysis of facet heating
in semiconductor lasers, Proc. SPIE 2005. in print
25. T.J. Ochalski, D. Pierscinska1,
A. Malag, Analysis of the Front Facet Temperature in
Laser Diode With Non Absorbing Mirror,
MRS Proc. Fall 2005 in print
SHORT DESCRIPTION OF OCHALSKI’S MAJOR ACCOMPLSHEMENTS
Tomasz Ochalski provided two parallel doctorates, he
spent 31 months outside country of origin. During his Ph.D. studies,
international visits and post doctoral fellowship he gained comprehensive
experience. The number of optical laboratories which he visited and number of
different experiments which he have built prove the level of skills of
researcher. His fascination is designing and developing complex optical
systems, physics of semiconductor heterostructures and devices and computer
analysis of the experimental data.
He create and coach optical spectroscopy analysis
group. His optical laboratory is versatile and world unique. The number of
complementary optical techniques placed in the same laboratory allowed his
group to perform experiments on the highest scientific level. The newest set-up
called thermoreflectance mapper is the only one such tool in the word which
allows imaging of the temperature of the working devices with spatial
resolution 0.6 mm. The most
recent results were obtained for quantum cascade laser and quantum dots laser.
His experience in optical techniques and knowledge of
laser diodes issue and finally practice in quantum dots based devices matched
him and project very well. His achievements prove potential to acquire new
knowledge and leadership qualities which are essential to achieve success of
the project.