CURRICULUM VITAE -
IOANNIS TOMKOS
December 1999
PERSONAL DATA
Last name
: TOMKOS
First name
: IOANNIS
Date of Birth
: 15 - 03 - 1973
Nationality
: Greek
Current Position
: Research Fellow, University of Athens
Address
: Irakleiou 366 - N. Irakleio, Athens, 14122
Telephone number
: +(301) 7275335(W), +(301) 2826884(H)
Fax number
: +(301) 7228981
E-mail address
: gtomkos@di.uoa.gr
Internet address
: www.di.uoa.gr/~gtomkos
EDUCATION
- UNIVERSITY OF ATHENS (1996 - 1999)
Ph.D. in Fiber Optic Communications, Department
of Informatics
- UNIVERSITY OF ATHENS (1994 - 1996)
M.Sc. in “Electronics and Telecommunications
Engineering”, (two year course).
- UNIVERSITY OF PATRAS (1990 - 1994)
B.Sc. in “Physics”, (four-year course).
- Native in Greek and fluency in English
POSITIONS HELD
- February 1997 - December 1999
Research fellow - “University of Athens”.
- November 1996 - January 1997
Research fellow - “Telecom Paris”.
- October 1994 - December 1999
Teaching Associate in University of Athens and
in Technical schools
RESEARCH ACTIVITIES
- Participation in the following Research
Programs, founded by the European Commission:
1996 - 1998 / ACTS “MIDAS” - AC053
/ “Multigigabit Interconnection using Dispersion
Compensation and Advanced Soliton Techniques”
1996 - 1998 / COST 240 /
“Techniques for modeling and measuring advanced
photonic telecommunications components”
1998 - 1999 / COST 267 /
“Semiconductor devices for optical signal processing”
1996 - 1997 / HCM Giga - pico /
- Participation in the following Research
Projects founded by the Greek Telecommunications
Organization (O.T.E.):
1998 - 1999 /ADSL Project/
“Design and implementation of an ADSL network”
- Simulation of the behavior of an optical automatic
frequency control (AFC) scheme and its
influence on a DPSK coherent optical communication
system (using the SPW software).
- Design and implementation of microwave
amplifiers and microstrip filters and antennas.
- Design and implementation of digital
filters for processing of digital signals.
ACHIEVEMENTS
- Awarded by SPIE, the International Society
for Optical Engineering, with an educational scholarship for potential
long-range contributions to the field of photonics (1999).
- Awarded by the Lasers and Electro-Optics Society
of the Institute of Electrical and Electronics Engineering (LEOS/IEEE),
as the winner of the 1998 IEEE/LEOS “Best Student Paper” (1999).
- Awarded by the Lasers and Electro-Optics Society
of the Institute of Electrical and Electronics
Engineering (LEOS/IEEE) with a travel grant in
order to present my work in the IEEE/LEOS ’98
Annual Meeting (1998).
- Awarded by the Greek National Institute of
Scholarships for my academic performance (1991, 1992, 1993).
TECHNICAL SKILLS
- Photonics: Experience with measurement
and analysis of bit-error rate, noise, and non-linear effects in photonic
devices and systems, especially wavelength-division multiplexed (WDM) systems.
Experience with photonic devices including fibre and semiconductor amplifiers,
optical transmitters and receivers, filters, and fibre transmission. Experience
with a wide variety of photonic measurement techniques.
- Electronics: Experience with high-speed
oscilloscopes, RF spectrum analyzers, network analyzers and a wide range
of RF equipment.
- Computing: Experience with programming.
Experienced user of Windows, DOS and Unix operating systems.
- Other:
(a) Responsible for the performance evaluation
and testing of ADSL access network technologies in national projects.
(b) Supervisor of M.Sc. and B.Sc. level thesis
of post- and under- graduate students.
(c) Highly developed written and oral communication
and presentation skills.
SHORT DESCRIPTION OF MY PH.D.
THESIS
The subject of my thesis was related to “Four
wave mixing (FWM) in semiconductor optical amplifiers (SOA) for applications
in all-optical communications systems and networks”. The main application
that FWM in SOAs can find is for wavelength conversion (a hot research
subject in the area of optical communications with many applications in
WDM and OTDM systems). Four wave mixing (FWM) has been acknowledged as
a promising technique for high capacity all-optical signal processing since
it is transparent to the modulation format and bit rate of the signal to
be converted. At the starting period of my thesis there were some unresolved
problems with the FWM-based technique. The main limitations were the sensitivity
to the signal polarization and the reduction of the conversion efficiency
for large wavelength shifts. The aim of my thesis was to experimentally
study and theoretically model the FWM process in semiconductor optical
amplifiers, and try to optimize its performance by developing novel schemes
that will overcome the limitations. Indeed, my research effort for these
purposes gave some new ideas that has enhanced significantly the performance
of this type of converters (optimization of various polarization insensitive
wavelength conversion schemes and wavelength conversion with constant efficiency
over more that 60nm). This performance enhancement has been studied also
in system applications (all-optical conversion of 10Gb/s signal over 21nm
and all-optical demultiplexing of a 4x10Gb/s OTDM signal with simultaneous
wavelength conversion of 19nm). During my thesis I have also studied the
FWM process in other semiconductor devices (single- and multi- section
DFB, and DBR laser diodes), and also in dispersion shifted fibers. The
aim of this study was to compare the performance among the different non-linear
media that could be used for FWM-based wavelength conversion. Finally,
I have activities in studying novel optical cross-connect architectures
employing wavelength conversion (wavelength interchangeable cross-connects).
The research in the above-described fields is still on going.
PUBLICATIONS IN INTERNATIONAL
JOURNALS AND CONFERENCES
(P1) I. Tomkos, I. Zacharopoulos, D.Syvridis,
T. Sphicopoulos, C. Caroumbalos, E. Roditi,
“Performance of a re-configurable wavelength
converter based on dual pump wave mixing in a semiconductor optical amplifier”,
IEEE Photonics Technology Letters, vol. 10, no. 10, October 1998.
(P2) I. Tomkos, I. Zacharopoulos, D.Syvridis,
T. Sphicopoulos, C. Caroumbalos, E. Roditi,
“Improved performance of a wavelength converter
based on dual pump four wave mixing technique”, AIP Applied Physics Letters,
vol.72, no. 20, May 1998.
(P3) I. Zacharopoulos, I. Tomkos, D. Syvridis,
T. Sphicopoulos, C. Caroumbalos, E. Roditi,
“Study of polarisation insensitive wave mixing
in bulk semiconductor optical amplifiers”, IEEE Photonics Technology Letters,
vol. 10, no. 3, pp. 352-354, March 1998.
(P4) I. Zacharopoulos, I. Tomkos, D.Syvridis,
F. Girardin, L. Occhi, G. Guekos,
“ Influence of phase mismatch on a spectral inverter
based on four wave mixing in dispersion shifted fiber at 10Gb/s”,
IEEE Photonics Technology Letters, vol.11, no.4,
p.p.430-432 April 1999.
(P5) I. Tomkos, I. Zacharopoulos, E. Roditi,
D. Syvridis, A. Uskov,
“Mechanisms of wave mixing and polarisation sensitivity
of the wavelength conversion in semiconductor optical amplifiers using
two parallel polarized pumps”, Optics Communications (163)1-3 (1999) pp.
49-54
(P6) I. Tomkos, I. Zacharopoulos, E. Roditi,
D.Syvridis, A. Uscov,
“On the polarization sensitivity and performance
optimization of a dual pump four wave mixing based wavelength converter”,
Optical and Quantum Electronics, 32(1): 97-113, January 2000.
(P7) I. Tomkos, I. Zacharopoulos, E. Roditi,
D.Syvridis,
“Experimental investigation of four wave mixing
in a 3-electrode distributed feedback laser”, Applied Physics letters,
vol. 75, no. 9, pp. 1195-1197, 1999.
(P8) I. Tomkos, R. Calvani, I. Zacharopoulos,
D.Syvridis, F. Cisternino, E. Riccardi,
“All Optical Demultiplexing of 4x10Gb/s Using
Dual Pump Wave Mixing in Semiconductor Optical Amplifier”,
Photonics Technology letters, vol. 11, no. 11,
pp. 1464-1466, 1999.
(P9) I. Tomkos, N. Andoniades, D. Syvridis,
“Modular and Re-configurable Parametric Wavelength
Interchanging Cross-Connect Architectures”, to be published, Photonics
Network Communications Journal (special issue on WDM Transport Networks).
(C1) I. Tomkos, R. Calvani, I. Zacharopoulos,
D.Syvridis, F. Cisternino, E. Riccardi, “All Optical
Demultiplexing of 40Gb/s OTDM signal with simultaneous
wavelength shift of 19nm”, LEOS’99 Annual Meeting, 8-11 November, San Francisco,
California, U.S.A.
(C2) I. Tomkos, N. Andoniades, D. Syvridis, “?
Modular and Re-configurable Parametric Wavelength
Interchanging Cross-Connect Architecture”, LEOS’99
Annual Meeting, 8-11 November, San Francisco, California, U.S.A.
(C3) I. Tomkos, I. Zacharopoulos, E. Roditi,
D.Syvridis, F. Girardin, L. Occhi, A. Uscov, “Highly
performing wavelength converter based on
dual pump wave mixing in semiconductor
optical amplifiers“, LEOS’98 Annual Meeting,
1-4 December, Orlando, Florida, U.S.A (awarded as the “IEEE/LEOS’98 Best
Student Paper”).
(C4) I. Tomkos, I. Zacharopoulos, E. Roditi,
D.Syvridis, “Experimental investigation of four wave
mixing in a 3-electrode distributed feedback
laser”, accepted for presentation in the European
Conference on Integrated Optics ECIO’99, 14-17
April 1999, Torino, Italy
(C5) I. Tomkos, I. Zacharopoulos, D.Syvridis,
“Dual pump wave mixing in semiconductor optical
amplifiers : Performance enhancement with long
amplifiers” (full article), Photonics West ’99 SPIE
International Conference, San Jose, U.S.A.
(C6) I. Tomkos, I. Zacharopoulos, E. Roditi,
D.Syvridis, A. Uscov, “On the polarization sensitivity of a
dual pump four wave mixing based wavelength converter”,
International Photonics Conference IPC’98, 15-19 December, Taipei, Taiwan
(C7) I. Tomkos, I. Zacharopoulos, D.Syvridis,
“An all-optical strict transparent wavelength conversion
technique suitable for integration in transparent
optical network nodes”, International Conference
on Telecommunications ICT’99, Korea.
(C8) I. Tomkos, I. Zacharopoulos, D.Syvridis,
T. Sphicopoulos, C. Caroumbalos, N. Theofanous, “Four
wave mixing based wavelength conversion in semiconductor
optical amplifiers : Experimental and
theoretical results”, SPIE 2nd International
Conference on New Laser Technologies and
Applications, 1-4 June 1997, Ancient Olympia,
Greece
(C9) I. Zacharopoulos, I. Tomkos, D.Syvridis,
“Optimization of dispersion shifted fiber phase conjugator
including zero dispersion wavelength variation
and polarization mode dispersion” (full article), Photonics West’99 SPIE
International Conference, San Jose, U.S.A.
(C10) I. Zacharopoulos, I. Tomkos, D.Syvridis,
“Comparison of midspan and multipoint spectral inversion
in high bit-rate optical links” (full article),
Photonics West’00 SPIE International Conference, San
Jose, U.S.A.
(C11) I. Zacharopoulos, I. Tomkos, D.Syvridis,
“Influence of fiber nonlinearities in the performance of an
all-optical fiber based demultiplexer” (full
article), Photonics West’00 SPIE International
Conference, San Jose, U.S.A.
(WS1) I. Tomkos, I. Zacharopoulos, D.Syvridis
“Wave mixing in semiconductor devices for optical signal
processing applications”, COST267 Workshop on
semiconductor devices for optical signal
processing, 22-24 April 1999, Rome.
(WS2) D.Syvridis, I. Tomkos, I. Zacharopoulos,
“Dual pump wave mixing: Polarization Sensitivity or
Enhanced Performance”, ACTS Projects, Photonics
domain workshop on WDM networks and
related technologies, 6-8 May 1998, Brussels
(WS3) I. Tomkos, I. Zacharopoulos, D.Syvridis,
“Terahertz four wave mixing in semiconductor optical
amplifiers. Experimental and theoretical results”,
HCM GIGA-PICO workshop 16-17 April 1997,
Rhodes, Greece
PROFESSIONAL MEMBERSHIPS
- Student Member
of IEEE-LEOS since 1998.
REFERENCES
- Available on request.