У оквиру сарадње са Лабораторијом за метаматеријале, Центра за фотонику, у читаоници библиотеке „Др Драган Поповић“ Института за физику у Београду у понедељак, 26. новембра у 12 часова проф. Томас Цвик (IEEE Fellow, Director of the Institute of Radio Frequency Engineering and Electronics, Karlsruhe Institute of Technology, Germany) ће одржати предавање:

Antenna integration in millimeter-wave transceivers for high volume applications

САЖЕТАК:

The enormous technological progress accomplished over the last decades facilitates the utilization of millimeter-wave (mmw) frequencies for mass products like automotive radars, industrial sensors, high-speed data communication links or medical applications. The main enablers are the semiconductor technologies with constantly improving cut-off frequencies reaching several hundred GHz. The dominant limiting factor though for the mass production of low-cost mmw systems above 100 GHz is that, suitable packaging technologies are not yet finally available. The major issue for the packaging is to find a proper way to get all signals in and out of the package, since at mmw frequencies interconnects are very difficult to realize and very lossy. One way out of the dilemma is to integrate the complete transceiver together with the antenna into one single package. Compactness is the key to low losses in mmw interconnects. This also means that the antenna must be integrated into the package.
In this talk, a short overview on the packaging and antenna integration concepts for mmw transceivers is provided together with several particular approaches. The different challenges for antenna integration and interconnects can be found in [1, 2, 3, 4, 5, 6]. In the second part, complete solutions are shown where in one case the mmw frontend is integrated together with off-chip antennas in a molded 8 mm by 8 mm QFN package [7] and in another case an on-chip antenna together with a lens is mounted in an 8 mm by 8 mm QFN package as well [8]. An application example of a complete radar system with the packaged transceiver soldered on a baseband PCB with microprocessor and lens above the chip to yield a narrow beam is shown. The complete module has a size of 35 mm x 35 mm x 25 mm and allows distance measurements with a high accuracy [9]. An outlook on packages for high data rate transmission conclude the talk [10].

REFERENCES

[1]    T. Zwick, S. Beer, „QFN based Packaging Concepts for Millimeter-Wave Transceivers,“ IEEE International Workshop on Antenna Technology (iWAT), Mar. 2012.
[2]    S. Beer, H. Gulan, M. Pauli, C. Rusch, G. Kunkel, T. Zwick, „122-GHz Chip-to-Antenna Wire Bond Interconnect with High Repeatability“, in IEEE Microwave Symposium Digest (MTT), 2012.
[3]    S. Beer, C. Rusch, H. Gulan, B. Göttel, M.G. Girma, J. Hasch, W. Winkler, W. Debski, T. Zwick, „An Integrated 122-GHz Antenna Array with Wire Bond Compensation for SMT Radar Sensors,“ IEEE Transactions on Antennas and Propagation, vol. 61, no. 12, Dec. 2013, pp. 5976-5983.
[4]    S. Beer, C. Rusch, B. Goettel, H. Gulan, M. Zwyssig, G. Kunkel, T. Zwick, „A Self-Compensating 130-GHz Wire Bond Interconnect with 13% Bandwidth,“ IEEE Antennas and Propagation Society International Symposium, July 2013.
[5]    S. Beer, H. Gulan, C. Rusch, T. Zwick, „Coplanar 122-GHz Antenna Array with Air Cavity Reflector for Integration in Plastic Packages“, IEEE Antennas and Wireless Propagation Letters, vol. 11, Jan. 2012, pp. 160-163.
[6]    B. Goettel, P. Pahl, C. Kutschker, S. Malz, U. Pfeiffer, T. Zwick, „Active Multiple Feed On-Chip Antennas With Efficient In-Antenna Power Combining Operating at 200–320 GHz“, IEEE Transactions on Antennas and Propagation, vol. 65, no. 2, Feb. 2017.
[7]    T. Zwick, F. Boes, A. Bhutani, B. Goettl, M. Pauli, „Pea-Sized mmW Transceivers“, IEEE Microwave Magazine, Sept. 2017, pp. 79-89.
[8]    B. Goettel, W. Winkler, A. Bhutani, F. Boes, M. Pauli, T. Zwick, „Packaging Solution for a Millimeter-Wave System-on-Chip Radar“, IEEE Transactions on Components, Packaging and Manufacturing Technology, vol. 8, no. 1, Jan 2018, pp. 73-81.
[9]    M. Pauli, B. Göttel, S. Scherr, A. Bhutani, S. Ayhan, W. Winkler, T. Zwick, „Miniaturized Millimeter-Wave Radar Sensor for High Accuracy Applications“, invited paper, IEEE Transactions on Microwave Theory and Techniques, vol. 65, no. 5, May 2017.
[10]    J. Eisenbeis, F. Boes, B. Goettel, S. Malz, U. Pfeiffer, T. Zwick, „30 Gbps Wireless Data Transmission with Fully Integrated 240 GHz Silicon Based Transmitter“, IEEE 17th Topical Meeting on Silicon Monolithic Integrated Circuits in RF Systems (SiRF), 2017, pp. 33-36.

У оквиру семинара Нискофонске лабораторије за нуклеарну физику, у уторак, 20. новембра у 12 часова у читаоници „Др Драган Поповић“ Института за физику у Београду др Горан Шкоро (ISIS Neutron and Muon Source, Rutherford Appleton
Laboratory, UK Research and Innovation, STFC, United Kingdom) ће одржати предавање:

2500 days at ISIS (based on a true story)

САЖЕТАК:

ISIS Neutron and Muon Source based at UK Research and Innovation’s STFC
Rutherford Appleton Laboratory (RAL) in Oxfordshire is a world-leading centre
for research in the physical and life sciences. It supports a national and
international community of more than 2000 scientists who use neutrons and
muons for research in physics, chemistry, materials science, geology,
engineering, and biology. It currently has a staff of around 400 people who
support the programme of more than 700 experiments entailing more than 3000
user days annually.

The role of nuclear physicist at spallation neutron source, or research
reactor, or any similar neutron production “factory” is, typically, to: create
and use the Monte Carlo model of the facility to help the instrument
scientists to get maximum from their instrumentation; calculate the build-up
of radionuclide inventories in activated materials; perform robust
measurements of particle fluxes and radiation dose rates in operational
environments; prepare the future research and development programmes and, last
but not least, provide consultancy and advisory support for similar activities
outside of home organization.

In this talk, after a short introduction about ISIS Neutron and Muon Source, a
typical day (averaged over seven years) in the life of a nuclear physicist at
a spallation neutron source will be described.

Научници са Института за примену нуклеарне енергије (ИНЕП) гостоваће на
Институту за физику у Београду како би представили своја истраживања и
отворили могућности за интензивнију сарадњу два института.

Представљање ИНЕП-а за истраживаче Института организовано је у среду,
14. новембра 2018. у 12 часова, у сали „Звонко Марић“. Догађај је
прилика да се размене драгоцене инфромације о текућим пројектима, али и
шансама за покретање нових.

ИНЕП је институт у непосредном суседству Института за физику који се
деценијама равијао у области примењене науке. Однедавно, откако је
Институт за физику постао институт од националног значаја, почела је
доректнија комуникација и сарадња два института.

У оквиру семинара Одељења комуникација Института за физику, у уторак, 13. новембра, у 12 часова, у сали „Звонко Марић“, Arnaud Marsollier, шеф комуникација ЦЕРН-а, одржаће предавање:

CERN Media Relations: Communications and modern physics

Предавач је гост Медијске лабораторије, школе научног новинарства која се организује на Институту за физику у Београду. Прчитајте више о комуникацијама у ЦЕРН-у.

У оквиру традиционалног семинара посвећеног историји науке и теорији сазнања, у уторак, 13. новембра у 2018. у 13 часова, академик Зоран Кнежевић из Астрономске опсерваторија у Београду одржаће предавање:

“Милутин Миланковић и астрономска теорија климатских промена: историјске контроверзе, Канон, докази”

Предавање се одржва у читаоници библиотеке „Др Драган Поповић“.

У оквиру семинара Центра за физику чврстог стања и нових материјала у среду, 7. новембра 2018. године у 14:30 часова, у читаоници „Др Драган Поповић“, проф. др Војислав Крстић (Department of Physics, Friedrich-Alexander-Universität, Erlangen, Germany) одржаће предавање:

Local Electronic Confinement in Graphene: From Raman Response of Covalent Derivatives to Optics with Electrons

САЖЕТАК:

Local electronic confinement is a key-ingredient for the successful control of electronic and optoelectronic properties of any material. In graphene however, due to its specific hexagonal lattice structure (two triangular sublattices) and the circumstance to be made of carbon atoms, electronic confinement can have many different flavours than just the localisation of electrons. Here we address two manifestations of electronic confinement, one mainly chemistry driven, the other driven by physical interactions:
Covalent functionalization of graphene is a continuously progressing field of research. However, in virtually all optical responses, an unresolved enhancement in peak intensity with increase of sp3 carbon content is observed. To elucidate this general phenomenon we present a phenomenological model [1] which takes into account the circumstance that upon covalent functionalization confined π-conjugated domains (photoluminescent) surrounded by sp3 carbon regions in graphene monolayers are formed.[2,3] Our model, underpinned by combined Raman measurements and an in-situ dry electrostatic doping technique, incorporates the modulation of the Raman intensities through the photoluminescence active domains, and correlates the individual D- and G-mode intensities to the degree of functionalization. Through this, evaluations of Raman spectra using our model circumvent the ambiguities and information loss encountered when using the ratio of D- and G-mode intensities. Physical confinement involves the use of potential barriers and wells in contrast to altering chemical bonds. However, the use of electrostatic potentials for confinement of the relativistic electrons in graphene is not efficient due to the Klein paradox. Nevertheless, the introduction of local electrostatic potentials is theoretically predicted to have a confining action in form of a caustic motion of electrons within the potential [4]. We will show that this effectively results in a guiding of electrons through scattering, which is the electronic analogue of the well-known Mie scattering [5].

РЕФЕРЕНЦЕ:

1. P. Vecera, S. Eigler, M. Koleśnik-Gray, V. Krstić, A. Vierck, J. Maultzsch, R. A. Schäfer, F. Hauke, A. Hirsch, Scientific Reports 7, 45165, DOI: 10.1038/srep45165 (2017)
2. J. Robertson, E.P. O’Reilly, Phys. Rev. B 35, 2946-2957 (1987).
3. F. Demichelis, S. Schreiter, A. Tagliaferro, Phys. Rev. B 51, 2143-2147 (1995).
4. R.L. Heinisch, F.X. Bronold, H. Fehske, Phys. Rev. B 87, 155409 (2013).
5. J.M. Caridad, S. Connaughton, C. Ott, H.B. Weber, V. Krstić, Nature Communications 7, 12894, DOI: 10.1038/NCOMMS12894 (2016)

У оквиру СЦЛ семинара Центра за физику комплексних система, у четвртак, 8. новембра 2018. године у 14 часова, у читаоници Института за физику „Др Драган Поповић“, Dr. Andreas Oestlin (Institute of physics, University of Augsburg, Germany), одржаће предавање:

Disorder and Correlation for Realistic Materials: a LDA+DMFT and CPA Approach

САЖЕТАК:

We introduce a computational scheme for calculating the electronic structure of random alloys that includes electronic correlations within the framework of the combined density functional and dynamical mean-field theory. By making use of the particularly simple parameterization of the electron Green’s function within the linearized muffin-tin orbitals method, it is possible to greatly simplify the embedding of the self-energy. This in turn facilitates the implementation of the coherent potential approximation, which is used to model the substitutional disorder. The computational technique is tested on the Cu-Pd binary alloy system, and for disordered Mn-Ni interchange in the half-metallic NiMnSb.