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Andreasson, Björn PererikORCID iD iconorcid.org/0000-0002-3764-4235
Publications (10 of 14) Show all publications
Friel, R., Gerling-Gedin, M., Nilsson, E. & Andreasson, B. P. (2019). 3D Printed Radar Lenses with Anti-Reflective Structures. Designs, 3(2), Article ID 28.
Open this publication in new window or tab >>3D Printed Radar Lenses with Anti-Reflective Structures
2019 (English)In: Designs, E-ISSN 2411-9660, Vol. 3, no 2, article id 28Article in journal (Refereed) Published
Abstract [en]

Background: The purpose of this study was to determine if 3D printed lenses with wavelength specific anti-reflective (AR) surface structures would improve beam intensity and thus radar efficiency for a Printed Circuit Board (PCB)-based 60 GHz radar. This would have potential for improved low-cost radar lenses for the consumer product market. Methods: A hyperbolic lens was designed in 3D Computer Aided Design (CAD) software and was then modified with a wavelength specified AR structure. Electromagnetic computer simulation was performed on both the ‘smooth’ and ‘AR structure’ lenses and compared to actual 60 GHz radar measurements of 3D printed polylactic acid (PLA) lenses. Results: The simulation results showed an increase of 10% in signal intensity of the AR structure lens over the smooth lens. Actual measurement showed an 8% increase in signal of the AR structure lens over the smooth lens. Conclusions: Low cost and readily available Fused Filament Fabrication (FFF) 3D printing has been shown to be capable of printing an AR structure coated hyperbolic lens for millimeter wavelength radar applications. These 3D Printed AR structure lenses are effective in improving radar measurements over non-AR structure lenses.

Place, publisher, year, edition, pages
Basel: MDPI, 2019
Keywords
radar, 3D printing, lenses, anti-reflective coatings, millimeter wave radar, simulation, additive manufacturing, quasi-optics
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:hh:diva-39695 (URN)10.3390/designs3020028 (DOI)
Funder
Knowledge Foundation, 2016/0303
Available from: 2019-06-11 Created: 2019-06-11 Last updated: 2019-07-31Bibliographically approved
Zalden, P., Quirin, F., Schumacher, M., Siegel, J., Wei, S., Koc, A., . . . Sokolowski-Tinten, K. (2019). Femtosecond x-ray diffraction reveals a liquid–liquid phase transition in phase-change materials. Science, 364(6445), 1062-1067
Open this publication in new window or tab >>Femtosecond x-ray diffraction reveals a liquid–liquid phase transition in phase-change materials
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2019 (English)In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 364, no 6445, p. 1062-1067Article in journal (Refereed) Published
Abstract [en]

In phase-change memory devices, a material is cycled between glassy and crystalline states. The highly temperature-dependent kinetics of its crystallization process enables application in memory technology, but the transition has not been resolved on an atomic scale. Using femtosecond x-ray diffraction and ab initio computer simulations, we determined the time-dependent pair-correlation function of phase-change materials throughout the melt-quenching and crystallization process. We found a liquid–liquid phase transition in the phase-change materials Ag4In3Sb67Te26 and Ge15Sb85 at 660 and 610 kelvin, respectively. The transition is predominantly caused by the onset of Peierls distortions, the amplitude of which correlates with an increase of the apparent activation energy of diffusivity. This reveals a relationship between atomic structure and kinetics, enabling a systematic optimization of the memory-switching kinetics. © 2019 American Association for the Advancement of Science.

Place, publisher, year, edition, pages
Washington, DC: American Association for the Advancement of Science, 2019
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:hh:diva-39862 (URN)10.1126/science.aaw1773 (DOI)000471306700040 ()31197008 (PubMedID)2-s2.0-85067625790 (Scopus ID)
Available from: 2019-06-19 Created: 2019-06-19 Last updated: 2019-09-09
Hagström, A. L., Vass, L., Liu, F., Gerling, M., Karlsson, P.-O., Nilsson, E. & Andreasson, B. P. (2018). An iterative approach to determine the refractive index of 3D printed 60GHz PLA lenses. In: Proceedings of the 14th Loughborough Antennas and Propagation Conference (LAPC 2018): . Paper presented at Loughborough Antennas and Propagation Conference 2018, LAPC 2018, Loughborough, United Kingdom, 12-13 November, 2018. Piscataway, N.J.: IEEE
Open this publication in new window or tab >>An iterative approach to determine the refractive index of 3D printed 60GHz PLA lenses
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2018 (English)In: Proceedings of the 14th Loughborough Antennas and Propagation Conference (LAPC 2018), Piscataway, N.J.: IEEE, 2018Conference paper, Published paper (Refereed)
Abstract [en]

This paper describes an iterative approach to determine quasi-optical properties of standard 3D printer filament material to, in an inexpensive and fast way, construct focusing lenses for millimetre wave systems. Results from three lenses with different focal lengths are shown and discussed. The real part of the permittivity at 60GHz for polylactic acid (PLA) is in this paper determined to be εr=2.74. © 2018 Institution of Engineering and Technology. All rights reserved.

Place, publisher, year, edition, pages
Piscataway, N.J.: IEEE, 2018
Series
IET Conference Publications ; CP746
Keywords
Additive manufacturing, radar, lenses, quasi-optics
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:hh:diva-38454 (URN)10.1049/cp.2018.1480 (DOI)2-s2.0-85061380873 (Scopus ID)978-1-78561-969-4 (ISBN)
Conference
Loughborough Antennas and Propagation Conference 2018, LAPC 2018, Loughborough, United Kingdom, 12-13 November, 2018
Funder
Knowledge Foundation, 20160303
Available from: 2018-11-29 Created: 2018-11-29 Last updated: 2019-04-24Bibliographically approved
Taha, W., Duracz, A., Zeng, Y., Atkinson, K., Bartha, F. Á., Brauner, P., . . . Grante, C. (2016). Acumen: An Open-source Testbed for Cyber-Physical Systems Research. In: Benny Mandler, Johann Marquez-Barja, Miguel Elias Mitre Campista, Dagmar Cagáňová, Hakima Chaouchi, Sherali Zeadally, Mohamad Badra, Stefano Giordano, Maria Fazio, Andrey Somov & Radu-Laurentiu Vieriu (Ed.), Internet of Things. IoT Infrastructures: Second International Summit, IoT 360° 2015, Rome, Italy, October 27-29, 2015. Revised Selected Papers, Part I. Paper presented at EAI International Conference on CYber physiCaL systems, iOt and sensors Networks (CYCLONE '15), Rome, Italy, October 26, 2015 (pp. 118-130). Heidelberg: Springer, 169
Open this publication in new window or tab >>Acumen: An Open-source Testbed for Cyber-Physical Systems Research
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2016 (English)In: Internet of Things. IoT Infrastructures: Second International Summit, IoT 360° 2015, Rome, Italy, October 27-29, 2015. Revised Selected Papers, Part I / [ed] Benny Mandler, Johann Marquez-Barja, Miguel Elias Mitre Campista, Dagmar Cagáňová, Hakima Chaouchi, Sherali Zeadally, Mohamad Badra, Stefano Giordano, Maria Fazio, Andrey Somov & Radu-Laurentiu Vieriu, Heidelberg: Springer, 2016, Vol. 169, p. 118-130Conference paper, Published paper (Refereed)
Abstract [en]

Developing Cyber-Physical Systems requires methods and tools to support simulation and verification of hybrid (both continuous and discrete) models. The Acumen modeling and simulation language is an open source testbed for exploring the design space of what rigorous-but-practical next-generation tools can deliver to developers of Cyber-Physical Systems. Like verification tools, a design goal for Acumen is to provide rigorous results. Like simulation tools, it aims to be intuitive, practical, and scalable. However, it is far from evident whether these two goals can be achieved simultaneously.

This paper explains the primary design goals for Acumen, the core challenges that must be addressed in order to achieve these goals, the "agile research method" taken by the project, the steps taken to realize these goals, the key lessons learned, and the emerging language design. © ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering 2016.

Place, publisher, year, edition, pages
Heidelberg: Springer, 2016
Series
Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, ISSN 1867-8211 ; 169
Keywords
Testbed, Cyber-Physical Systems (CPS), Modeling, Simulation, Hybrid Systems, Open Source Software
National Category
Computer Sciences
Identifiers
urn:nbn:se:hh:diva-29592 (URN)10.1007/978-3-319-47063-4_11 (DOI)000398616500011 ()2-s2.0-85000500985 (Scopus ID)978-3-319-47062-7 (ISBN)978-3-319-47063-4 (ISBN)
Conference
EAI International Conference on CYber physiCaL systems, iOt and sensors Networks (CYCLONE '15), Rome, Italy, October 26, 2015
Funder
Knowledge FoundationVINNOVA, 2011-01819
Note

This work was supported by US NSF award CPS-1136099, the Swedish Knowledge Foundation (KK), The Center for Research on Embedded Systems (CERES), and VINNOVA (Dnr. 2011-01819).

Available from: 2015-10-08 Created: 2015-10-08 Last updated: 2018-03-22Bibliographically approved
Persson, A. I., Enquist, H., Jurgilaitis, A., Andreasson, B. P. & Larsson, J. (2015). Real-time observation of coherent acoustic phonons generated by an acoustically mismatched optoacoustic transducer using x-ray diffraction. Journal of Applied Physics, 118(18), Article ID 185308.
Open this publication in new window or tab >>Real-time observation of coherent acoustic phonons generated by an acoustically mismatched optoacoustic transducer using x-ray diffraction
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2015 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 118, no 18, article id 185308Article in journal (Refereed) Published
Abstract [en]

The spectrum of laser-generated acoustic phonons in indium antimonide coated with a thin nickel film has been studied using time-resolved x-ray diffraction. Strain pulses that can be considered to be built up from coherent phonons were generated in the nickel film by absorption of short laser pulses. Acoustic reflections at the Ni-InSb interface leads to interference that strongly modifies the resulting phonon spectrum. The study was performed with high momentum transfer resolution together with high time resolution. This was achieved by using a third-generation synchrotron radiation source that provided a high-brightness beam and an ultrafast x-ray streak camera to obtain a temporal resolution of 10 ps. We also carried out simulations, using commercial finite element software packages and on-line dynamic diffraction tools. Using these tools, it is possible to calculate the time-resolved x-ray reflectivity from these complicated strain shapes. The acoustic pulses have a peak strain amplitude close to 1%, and we investigated the possibility to use this device as an x-ray switch. At a bright source optimized for hard x-ray generation, the low reflectivity may be an acceptable trade-off to obtain a pulse duration that is more than an order of magnitude shorter. © 2015 Author(s).

Place, publisher, year, edition, pages
New York: American Institute of Physics (AIP), 2015
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:hh:diva-29816 (URN)10.1063/1.4935269 (DOI)000365041700042 ()2-s2.0-84947231955 (Scopus ID)
Available from: 2015-11-25 Created: 2015-11-25 Last updated: 2017-12-01Bibliographically approved
Jurgilaitis, A., Enquist, H., Andreasson, B. P., Persson, A. I., Borg, B. M., Caroff, P., . . . Larsson, J. (2014). Time-Resolved X-ray Diffraction Investigation of the Modified Phonon Dispersion in InSb Nanowires. Nano letters (Print), 14(2), 541-546
Open this publication in new window or tab >>Time-Resolved X-ray Diffraction Investigation of the Modified Phonon Dispersion in InSb Nanowires
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2014 (English)In: Nano letters (Print), ISSN 1530-6984, E-ISSN 1530-6992, Vol. 14, no 2, p. 541-546Article in journal (Refereed) Published
Abstract [en]

The modified phonon dispersion is of importance for understanding the origin of the reduced heat conductivity in nanowires. We have measured the phonon dispersion for 50 nm diameter InSb (111) nanowires using time-resolved X-ray diffraction. By comparing the sound speed of the bulk (3880 m/s) and that of a classical thin rod (3600 m/s) to our measurement (2880 m/s), we conclude that the origin of the reduced sound speed and thereby to the reduced heat conductivity is that the C44 elastic constant is reduced by 35% compared to the bulk material. © 2014 American Chemical Society.

Place, publisher, year, edition, pages
Washington, DC: American Chemical Society (ACS), 2014
Keywords
elastic properties, indium antimonide, Nanowires, thermal conductivity, time dependent, X-ray diffraction
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:hh:diva-26520 (URN)10.1021/nl403596b (DOI)000331343900022 ()24387246 (PubMedID)2-s2.0-84894178785 (Scopus ID)
Available from: 2014-09-17 Created: 2014-09-17 Last updated: 2017-12-05Bibliographically approved
Pham, T. V., Rao, M., Andreasson, B. P., Peng, Y., Wang, J. & Jinesh, K. B. (2013). Photocarrier generation in CuxO thin films deposited by radio frequency sputtering. Applied Physics Letters, 102(3), Article number: 032101
Open this publication in new window or tab >>Photocarrier generation in CuxO thin films deposited by radio frequency sputtering
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2013 (English)In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 102, no 3, p. Article number: 032101-Article in journal (Refereed) Published
Abstract [en]

Copper oxides (CuxO) thin films were deposited using radio frequency (RF) sputtering on glass substrates. By tuning the argon (Ar) partial pressure during deposition, cuprous oxide (Cu2O), cupric oxide (CuO), or their mixed phase could be achieved. Drastic variations in the Hall mobility, hole density, and resistivity of the samples were observed due to the presence of different phases in the films. Kelvin probe studies indicate that the photo-generated carriers have lower recombination rate in pure Cu 2O phase. This was further validated by transient absorption measurements, where the estimated carrier lifetime for Cu2O was much larger that other phases. © 2013 American Institute of Physics.

Place, publisher, year, edition, pages
College Park, MD: American Institute of Physics (AIP), 2013
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:hh:diva-26521 (URN)10.1063/1.4788680 (DOI)000314032600045 ()2-s2.0-84872934025 (Scopus ID)
Available from: 2014-09-17 Created: 2014-09-17 Last updated: 2017-12-05Bibliographically approved
Karthik, K. R., Andreasson, B. P., Sun, C., Pramana, S. S., Varghese, B., Sow, C. H., . . . Mhaisalkar, S. G. (2011). Physical and Electrical Properties of Single Zn2SnO4 Nanowires. Electrochemical and solid-state letters, 14(1), K5-K7
Open this publication in new window or tab >>Physical and Electrical Properties of Single Zn2SnO4 Nanowires
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2011 (English)In: Electrochemical and solid-state letters, ISSN 1099-0062, E-ISSN 1944-8775, Vol. 14, no 1, p. K5-K7Article in journal (Refereed) Published
Abstract [en]

Electrical characterizations of single Zn2SnO4 (ZTO) nanowire devices are presented. These include resistivity, mobility, and photosensing measurements. The resistivity and the mobility of the Zn2SnO4 nanowire were measured to be 5.6 cm and 0.2 cm2/Vs, respectively. These values were found to be strongly dependent on the amount of electron-donating defects and less dependent on the thickness of the nanowires. An increase in the resistivity when changing the ambient atmosphere is observed. This change is caused by defect states lying in the bandgap, as shown by photoluminescence. The results imply the potential of ZTO nanowires as phototransistors and other photosensitive devices. © 2010 The Electrochemical Society.

Place, publisher, year, edition, pages
Pennington, NJ: Electrochemical Society, 2011
Keywords
carrier mobility, defect states, electrical resistivity, energy gap, nanowires, photoluminescence, semiconductor materials, semiconductor quantum wires, zinc compounds
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:hh:diva-26522 (URN)10.1149/1.3505875 (DOI)000284317600032 ()2-s2.0-78751549000 (Scopus ID)
Available from: 2014-09-17 Created: 2014-09-17 Last updated: 2017-12-05Bibliographically approved
Mathews, N., Varghese, B., Sun, C., Thavasi, V., Andreasson, B. P., Sow, C. H., . . . Mhaisalkar, S. G. (2010). Oxide nanowire networks and their electronic and optoelectronic characteristics. Nanoscale, 2(10), 1984-1998
Open this publication in new window or tab >>Oxide nanowire networks and their electronic and optoelectronic characteristics
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2010 (English)In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 2, no 10, p. 1984-1998Article in journal (Refereed) Published
Abstract [en]

Oxide nanowire networks or oxide nanonets leverage some of the exceptional functionalities of one-dimensional nanomaterials along with the fault tolerance and flexibility of interconnected nanowires to creating exciting opportunities in large-area electronics as well as green energy systems. This paper reviews the electronic and optoelectronic properties of these networks and highlights their potential applications in field-effect transistors, optoelectronic devices, and solar cells. Techniques to grow nanowires and their subsequent integration into networks using contact printing and electrospinning are described. Electrical properties of field-effect transistors fabricated from contact printed nanowire networks are discussed, and means of integration of the nanowire networks of heterogenous materials that enable ambipolar device operation are outlined. Photocurrent properties of these nanowires are described, including the dye sensitization of large-bandgap SnO2 nanowires. The final section deals with the advantages of employing nanowire networks in dye-sensitized solar cells and the dependence of solar cell performance on morphology and surface area. © The Royal Society of Chemistry 2010.

Place, publisher, year, edition, pages
Cambridge: RSC Publishing, 2010
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:hh:diva-26523 (URN)10.1039/c0nr00285b (DOI)000282686200012 ()2-s2.0-77957921895 (Scopus ID)
Available from: 2014-09-17 Created: 2014-09-17 Last updated: 2017-12-05Bibliographically approved
Andreasson, B. P., Janousch, M., Staub, U., Todorova, T., Delley, B., Meijer, G. I. & Pomjakushina, E. (2009). Detecting oxygen vacancies in SrTiO3 by 3d transition-metal tracer ions. Physical Review B. Condensed Matter and Materials Physics, 80(21), Article number: 212103
Open this publication in new window or tab >>Detecting oxygen vacancies in SrTiO3 by 3d transition-metal tracer ions
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2009 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 80, no 21, p. Article number: 212103-Article in journal (Refereed) Published
Abstract [en]

X-ray absorption experiments on 3d transition-metal tracer ions in SrTiO3 are presented. The absorption spectra of the tracer-ion changed upon reduction in the SrTiO3. This change is due to an oxygen vacancy created at the tracer-ion site. This finding is supported by density-functional theory calculations, which prove that the oxygen vacancies preferentially are created at the tracer-ion sites. Using the chemical sensitivity of x-ray absorption spectroscopy, tracer ions can be used to detect oxygen vacancies in SrTiO3 and possibly in other oxide systems. © 2009 The American Physical Society.

Place, publisher, year, edition, pages
College Park, MD: American Physical Society, 2009
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:hh:diva-26524 (URN)10.1103/PhysRevB.80.212103 (DOI)000273228200003 ()2-s2.0-77954730883 (Scopus ID)
Available from: 2014-09-17 Created: 2014-09-17 Last updated: 2017-12-05Bibliographically approved
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ORCID iD: ORCID iD iconorcid.org/0000-0002-3764-4235

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