Johannes Skaar

Professor - Theoretical Physics
Image of Johannes Skaar
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Mobile phone +47 48497352 48497352
Room Ø373
Username
Visiting address Sem Sælands vei 24 Fysikkbygningen 0371 Oslo
Postal address Postboks 1048 Blindern 0316 Oslo

100 % position at the Dep. of Physics, UiO. Before 2017, at NTNU.

Research

Quantum field theory, quantum optics, electromagnetics, metamaterials, photonics, quantum information.

Teaching

  • Fall 2023: FYS4170 Relativistic quantum field theory
  • Spring 2023: FYS1005 Classical mechanics
Tags: Light, quantum field theory, quantum optics, quantum information, quantum cryptography, quantum physics, electromagnetics, metamaterials, photonics, physics in everyday life

Publications

  • Gulla, Jan; Ryen, Kai & Skaar, Johannes (2023). Limits for realizing single photons. Physical Review A (PRA). ISSN 2469-9926. 108(6). doi: 10.1103/PhysRevA.108.063708. Full text in Research Archive
  • Ryen, Kai; Gulla, Jan & Skaar, Johannes (2022). Strictly Localized Three-Dimensional States Close to Single Photons. International journal of theoretical physics. ISSN 0020-7748. 61(5). doi: 10.1007/s10773-022-05133-7. Full text in Research Archive
  • Gulla, Jan & Skaar, Johannes (2021). Tunneling times of single photons. Journal of the Optical Society of America. B, Optical physics. ISSN 0740-3224. 38(11), p. 3457–3465. doi: 10.1364/JOSAB.437386. Full text in Research Archive
  • Gulla, Jan & Skaar, Johannes (2021). Approaching Single-Photon Pulses. Physical Review Letters. ISSN 0031-9007. 126(7). doi: 10.1103/PhysRevLett.126.073601. Full text in Research Archive
  • Skaar, Johannes (2019). Fresnel's equations in statics and quasistatics. European Journal of Physics. ISSN 0143-0807. 40(4). doi: 10.1088/1361-6404/ab166b. Full text in Research Archive
  • Hågenvik, Hans Olaf & Skaar, Johannes (2019). Magnetic permeability in Fresnel’s equation . Journal of the Optical Society of America. B, Optical physics. ISSN 0740-3224. 36(5), p. 1386–1395. doi: 10.1364/JOSAB.36.001386. Full text in Research Archive
  • Skaar, Johannes; Hågenvik, Hans Olaf & Dirdal, Christopher Andrew (2019). Four definitions of magnetic permeability for periodic metamaterials. Physical review B (PRB). ISSN 2469-9950. 99(6). doi: 10.1103/PhysRevB.99.064407. Full text in Research Archive
  • Joshi, Siddarth Koduru; Pienaar, Jacques; Ralph, Timothy C.; Cacciapuoti, Luigi; McCutcheon, Will & Rarity, John [Show all 45 contributors for this article] (2018). Space QUEST mission proposal: experimentally testing decoherence due to gravity. New Journal of Physics. ISSN 1367-2630. 20:063016(6), p. 1–22. doi: 10.1088/1367-2630/aac58b. Full text in Research Archive
  • Dirdal, Christopher Andrew; Hågenvik, Hans Olaf; Haave, Haakon Aamodt & Skaar, Johannes (2018). Higher order multipoles in metamaterial homogenization . IEEE Transactions on Antennas and Propagation. ISSN 0018-926X. 66(11), p. 6403–6407. doi: 10.1109/TAP.2018.2863742. Full text in Research Archive
  • Dirdal, Christopher Andrew & Skaar, Johannes (2018). Diamagnetism and the dispersion of the magnetic permeability. European Physical Journal B : Condensed Matter Physics. ISSN 1434-6028. 91(6). doi: 10.1140/epjb/e2018-80515-1. Full text in Research Archive
  • Marøy, Øystein; Makarov, Vadim & Skaar, Johannes (2017). Secure detection in quantum key distribution by real-time calibration of receiver. Quantum Science and Technology. ISSN 2058-9565. 2(4). doi: 10.1088/2058-9565/aa83c9. Full text in Research Archive
  • Hågenvik, Hans Olaf; Bløtekjær, Kjell & Skaar, Johannes (2017). Dielectric media considered as vacuum with sources. American Journal of Physics (AJP). ISSN 0002-9505. 85(11), p. 830–833. doi: 10.1119/1.5003810. Full text in Research Archive
  • Svendsen, Guro Kristin; Skaar, Johannes; Weman, Helge & Dupertuis, Marc-André (2015). Symmetries and optical transitions of hexagonal quantum dots in GaAs/AlGaAs nanowires. Physical Review B. Condensed Matter and Materials Physics. ISSN 1098-0121. 92(20). doi: 10.1103/PhysRevB.92.205303.
  • Hågenvik, Hans Olaf & Skaar, Johannes (2015). Fourier-Laplace analysis and instabilities of a gainy slab. Journal of the Optical Society of America. B, Optical physics. ISSN 0740-3224. 32(9), p. 1947–1953. doi: 10.1364/JOSAB.32.001947.
  • Hågenvik, Hans Olaf; Malema, Markus Edward & Skaar, Johannes (2015). Fourier theory of linear gain media. Physical Review A. Atomic, Molecular, and Optical Physics (PRA). ISSN 1050-2947. 91(4). doi: 10.1103/PhysRevA.91.043826.
  • Dirdal, Christopher Andrew; Bondevik, Tarjei & Skaar, Johannes (2015). Relaxed dispersion constraints and metamaterial effective parameters with physical meaning for all frequencies. Physical Review B. Condensed Matter and Materials Physics. ISSN 1098-0121. 91(13). doi: 10.1103/PhysRevB.91.134102.
  • Dirdal, Christopher Andrew & Skaar, Johannes (2015). Superposing Lorentzian resonance functions towards engineering target responses. In Zouhdi, Said; Zheludev, Nikolay & Teng, Jing Hua (Ed.), Meta'14 Singapore Proceedings. META conference. ISSN 978-2-9545460-4-9. p. 53–58.
  • Bugge, Audun Nystad; Sauge, Sebastien; Ghazali, Aina Mardhiyah M.; Skaar, Johannes; Lydersen, Lars Vincent Van de Wiel & Makarov, Vadim (2014). Laser damage helps the eavesdropper in quantum cryptography. Physical Review Letters. ISSN 0031-9007. 112(7:070503). doi: 10.1103/PhysRevLett.112.070503.
  • Marøy, Øystein; Gudmundsen, Magne; Lydersen, Lars Vincent Van de Wiel & Skaar, Johannes (2014). Error estimation, error correction and verification in quantum key distribution. IET Information Security. ISSN 1751-8709. 8(5), p. 277–282. doi: 10.1049/iet-ifs.2012.0333.
  • Liu, Qin; Lamas-Linares, Antia; Kurtsiefer, Christian; Skaar, Johannes; Makarov, Vadim & Gerhardt, Ilja (2014). A universal setup for active control of a single-photon detector. Review of Scientific Instruments. ISSN 0034-6748. 85(1). doi: 10.1063/1.4854615.
  • Dirdal, Christopher Andrew & Skaar, Johannes (2013). Superpositions of Lorentzians as the class of causal functions. Physical Review A. Atomic, Molecular, and Optical Physics (PRA). ISSN 1050-2947. 88(3). doi: 10.1103/PhysRevA.88.033834.
  • Dirdal, Christopher Andrew & Skaar, Johannes (2013). Negative refraction in causal media by evaluating polar paths for rational functions. Journal of the Optical Society of America. B, Optical physics. ISSN 0740-3224. 30(2), p. 370–376. doi: 10.1364/JOSAB.30.000370.
  • Svendsen, Guro Kristin; Haakestad, Magnus Willum & Skaar, Johannes (2013). Reciprocity and the scattering matrix of waveguide modes. Physical Review A. Atomic, Molecular, and Optical Physics (PRA). ISSN 1050-2947. 87(1). doi: 10.1103/PhysRevA.87.013838.
  • Skaar, Johannes & Haakestad, Magnus Willum (2012). Inverse scattering of dispersive stratified structures. Journal of the Optical Society of America. B, Optical physics. ISSN 0740-3224. 29(9), p. 2438–2445. doi: 10.1364/JOSAB.29.002438.
  • Svendsen, Guro Kristin; Weman, Helge & Skaar, Johannes (2012). Investigations of Bragg reflectors in nanowire lasers. Journal of Applied Physics. ISSN 0021-8979. 111(12). doi: 10.1063/1.4729529.
  • Grepstad, Jon Olav & Skaar, Johannes (2011). Does evanescent gain exist? In Stone, W. Ross (Eds.), Proceedings of the XXXth URSI General Assembly in Istanbul (August 2011). IEEE conference proceedings. ISSN 978-1-4244-5117-3. doi: 10.1109/ursigass.2011.6123712.
  • Grepstad, Jon Olav & Skaar, Johannes (2011). Total internal reflection and evanescent gain. Optics Express. ISSN 1094-4087. 19(22), p. 21404–21418. doi: 10.1364/OE.19.021404. Full text in Research Archive
  • Lydersen, Lars Vincent Van de Wiel; Akhlaghi, Mohsen K.; Majedi, A. Hamed; Skaar, Johannes & Makarov, Vadim (2011). Controlling a superconducting nanowire single-photon detector using tailored bright illumination. New Journal of Physics. ISSN 1367-2630. 13. doi: 10.1088/1367-2630/13/11/113042. Full text in Research Archive

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  • Skaar, Johannes (2023). Det er ett strømspareråd som nesten aldri nevnes. Aftenposten (morgenutg. : trykt utg.). ISSN 0804-3116.
  • Nilsen, Fabian Skalleberg & Skaar, Johannes (2020). Østlandssendingen - er det mulig å forsyne seg selv med strøm ved hjelp av spinningsykler og tredemøller? [Radio]. NRK P1.
  • Skaar, Johannes (2019). Intervju av TV2 Nyhetskanalen, kl 0710, om kvantedatamaskiner. [TV]. TV2 Nyhetskanalen.
  • Jemterud, Torkild; Skaar, Johannes; Eidsvoll, David & Iqbal, Yasmin Sofia (2019). Abels tårn. [Radio]. NRK P2 .
  • Risan, Lars & Skaar, Johannes (2019). SENT-kveld på Teknisk museum: Foredrag om kvantedatamaskiner.
  • Skaar, Johannes (2019). Musikk og matematikk.
  • Fedorov, Aleksey; Gerhardt, Ilja; Huang, Anqi; Jogenfors, Jonathan; Kurochkin, Yury & Lamas-Linares, Antia [Show all 11 contributors for this article] (2019). Comment on 'Inherent security of phase coding quantum key distribution systems against detector blinding attacks' (2018 Laser Phys. Lett. 15 095203). Laser Physics Letters. ISSN 1612-2011. 16. doi: 10.1088/1612-202X/aaf22d.
  • Dirdal, Christopher Andrew; Hågenvik, Hans Olaf; Haave, Haakon Aamodt & Skaar, Johannes (2018). Higher order multipoles in metamaterial homogenization.
  • Skaar, Johannes (2018). Fysikk og musikk.
  • Skaar, Johannes (2018). Energi - uten en tråd.
  • Skaar, Johannes (2018). Matematikk i musikk.
  • Andersen, Elise Rønnevig; Bratberg, Øivind; Hellum, Mari Kjos; Hjelle, Ole Petter; Hussein, Bassam & Lie, Anne Helene Kveim [Show all 11 contributors for this article] (2017). Landets beste forelesere svarer: Slik studerer du mest effektivt. [Newspaper]. Aftenposten.
  • Stensvold, Tore & Skaar, Johannes (2017). Norwegian Tech Awards 2017 - WÄRTSILÄ. De lader ferge med 1,2 megawatt effekt - uten fysisk kontakt med fartøyet. [Business/trade/industry journal]. Teknisk ukeblad.
  • Skaar, Johannes (2017). Musikkens fysikk.
  • Sund, Steinar & Skaar, Johannes (2017). Snart kan du lade med klærne. [Journal]. Aftenposten Vitenskap.
  • Mauren, Arnfinn & Skaar, Johannes (2017). Magisk teknologi kan bety farvel til hacking. [Business/trade/industry journal]. Aftenposten Vitenskap.
  • Sævik, Bjørnar Torvholm; Folven, Erik; Jahre, Magnus & Skaar, Johannes (2017). Ein æra er omm. [Internet]. nrk.no.
  • Klingenberg, Mathias & Skaar, Johannes (2017). 100 milliarder bilder i sekundet fanger lys som går raskere enn seg selv. [Business/trade/industry journal]. Teknisk ukeblad.
  • Sande, Anniken & Skaar, Johannes (2017). Her og nå: Dagens gjest. [Radio]. NRK P1.
  • Skaar, Johannes & Tollersrud, Emma (2017). Med lønnsøkning skal underviserne skinne. [Newspaper]. Morgenbladet.
  • Opheim, Aagot & Skaar, Johannes (2017). Vil gi ære, status og høyere lønn til de beste underviserne. [Newspaper]. Adresseavisen.
  • Skaar, Johannes (2016). Magneter, metallrør og usynlighetskapper.
  • Indregard, Sigve & Skaar, Johannes (2016). Til Mars med mikrobølgeovn. [Newspaper]. Morgenbladet.
  • Bakken, Kjersti & Skaar, Johannes (2016). Norgesglasset: "Lærer man egentlig noe av forelesninger, eller trenger studentene noe helt annet for å bli flinke?". [Radio]. NRK P1.
  • Skaar, Johannes (2016). Kortforedrag om musikk og fysikk.
  • Tollersrud, Emma & Skaar, Johannes (2016). «Hvis vi ikke underviser, er det lett å ta elementære ting for gitt.». [Newspaper]. Morgenbladet.
  • Kleiven, David; Skjønsfjell, Eirik Torbjørn Bakken; Zontone, Federico; Chushkin, Yuriy; Skaar, Johannes & Breiby, Dag Werner (2016). Experimental and Numerical Studies for Improved Coherent Diffraction Phase Retrieval.
  • Dirdal, Christopher Andrew; Hågenvik, Hans Olaf & Skaar, Johannes (2016). Higher order terms and origin dependence in metamaterial homogenization.
  • Dirdal, Christopher Andrew; Hågenvik, Hans Olaf & Skaar, Johannes (2016). Permittivity, permeability, and the significance of the electrical quadrupole in metamaterials.
  • Hågenvik, Hans Olaf; Dirdal, Christopher Andrew & Skaar, Johannes (2016). Homogenization of metamaterials: comparison and analysis.
  • Skaar, Johannes (2015). Maxwells teori og Hertz' eksperiment – grunnlaget for moderne telekommunikasjon ble skapt for 150 år siden.
  • Skaar, Johannes (2015). Hva er lys?
  • Dirdal, Christopher Andrew & Skaar, Johannes (2015). Giving Freedom and Physical Meaning to the Effective Parameters of Metamaterials for all Frequencies.
  • Hågenvik, Hans Olaf & Skaar, Johannes (2015). Laplace-Fourier analysis and instabilities of an active slab.
  • Jegtvik, Karin & Skaar, Johannes (2015). Er du vinneren av påskefjellet? [Internet]. nrk.no.
  • Ramsdal, Roar & Skaar, Johannes (2015). Her sendes 10 kilowatt trådløst. [Internet]. Teknisk ukeblad.
  • Dirdal, Christopher Andrew & Skaar, Johannes (2014). Superposing Lorentzian functions towards engineering target responses. The 5th International Conference on Metamaterials, Photonic Crystals and Plasmonics Book of Abstracts.
  • Dirdal, Christopher Andrew & Skaar, Johannes (2014). Superposing Lorentzian functions towards engineering target responses.
  • Dirdal, Christopher Andrew & Skaar, Johannes (2014). Metamaterial responses beyond the Kramers-Kronig relations.
  • Børringbo, Klaus & Skaar, Johannes (2014). Trådløs strøm – snart er den her. [Newspaper]. Aftenposten.
  • Dalløkken, Per Erlien; Skaar, Johannes & Samset, Bjørn Hallvard (2014). «Metamaterialer» skal beskytte piloter mot laserangrep fra bakken. [Internet]. Teknisk ukeblad.
  • Svendsen, Guro Kristin; Skaar, Johannes; Weman, Helge & Dupertuis, M.-A. (2014). Symmetries and optical transitions of hexagonal quantum dots in GaAs/AlGaAs nanowires.
  • Iversen, Marita Løvmo; Jansrud, Line & Skaar, Johannes (2014). Går det an å gjøre noe usynlig? NRK Newton. [TV]. NRK 1.
  • Schirber, Michael; Bugge, Audun Nystad; Sauge, Sebastien; Ghazali, Aina; Skaar, Johannes & Lydersen, Lars Vincent Van de Wiel [Show all 7 contributors for this article] (2014). Synopsis: Cyberattack by Breaking and Entering. [Internet]. APS Physics.
  • Andreassen, Katrine; Skaar, Johannes; Løland, Anders & Rolén, Tage (2014). Finn ut om du er en sinke på ski. [Internet]. klikk.no.
  • Brandslet, Steinar; Skaar, Johannes; Løland, Anders & Rolén, Tage (2014). Hvor fort går du på ski? Aftenposten (morgenutg. : trykt utg.). ISSN 0804-3116.
  • Lydersen, Lars Vincent Van de Wiel & Skaar, Johannes (2013). Kvantekryptografi. Fra Fysikkens Verden. ISSN 0015-9247. 75(1).
  • Skaar, Johannes; Løland, Anders; Rolén, Tage & Kokkegård, Hanne (2013). Vild med tal? Tæl dig frem til, om du er hurtigst. [Internet]. dr.dk.
  • Flæten, Sigurd Øygarden & Skaar, Johannes (2013). Laser kan bli fremtidens spionkamera. [Internet]. Teknisk ukeblad.
  • Brandslet, Steinar; Skaar, Johannes; Løland, Anders & Rolén, Tage (2013). Hvor fort går du på ski? [Internet]. forsking.no.
  • Brandslet, Steinar; Skaar, Johannes; Løland, Anders & Rolén, Tage (2013). Hvor fort går du på ski? Gemini. ISSN 0802-085X. p. 6–7.
  • Moe, Enok & Skaar, Johannes (2013). Rockheim forstyrrer flytrafikken på Værnes. Adresseavisen. ISSN 0805-3804.
  • Haugen, Vegard & Skaar, Johannes (2013). Døde av elektrosjokk med iPhone 5 i hånden. VG : Verdens gang. ISSN 0805-5203.
  • Haugen, Vegard & Skaar, Johannes (2013). Døde av elektrosjokk med iPhone 5 i hånden. [Internet]. amobil.no.
  • Grepstad, Jon Olav; Kaspar, Peter; Johansen, Ib-Rune; Skaar, Johannes; Sudbø, Aasmund & Solgaard, Olav (2012). Optical detection of single biomolecules using photonic-crystal membranes.
  • Time, Jon Kåre & Skaar, Johannes (2012). Trollmannen fra Tyrifjord. [Newspaper]. Morgenbladet.
  • Time, Jon Kåre & Skaar, Johannes (2012). I bakvendtland der alt går an. [Newspaper]. Morgenbladet.
  • Bugge, Audun Nystad; Sauge, Sebastien; Ghazali, Aina; Skaar, Johannes; Lydersen, Lars Vincent Van de Wiel & Makarov, Vadim (2012). Laser damage of photodiodes helps the eavesdropper.
  • Miller, Johanna; Makarov, Vadim; Kurtsiefer, Christian; Liu, Qin & Skaar, Johannes (2011). "Faked states" mimic quantum entanglement. [Internet]. Physics Today.
  • Voss, David; Makarov, Vadim; Kurtsiefer, Christian; Liu, Qin & Skaar, Johannes (2011). Synopsis: Eve Fools Alice and Bob. [Internet]. Physics.
  • Merali, Zeeya; Makarov, Vadim; Liu, Qin & Skaar, Johannes (2011). Lasers illuminate quantum security loophole. [Internet]. Nature News.
  • Zyga, Lisa; Makarov, Vadim; Liu, Qin & Skaar, Johannes (2011). Fake violations of Bell tests reinforce importance of closing loopholes. [Internet]. PhysOrg.com.
  • Lee, Chris; Makarov, Vadim; Liu, Qin & Skaar, Johannes (2011). Researchers show how to break quantum cryptography by faking quantum entanglement. [Internet]. Ars Technica.
  • Makarov, Vadim; Liu, Qin; Skaar, Johannes & Goodin, Dan (2011). Uncrackable quantum crypto undermined by new attack. [Internet]. The Register.
  • Scharf, Rainer; Makarov, Vadim; Liu, Qin & Skaar, Johannes (2011). Quantenkryptographie: Bell-Ungleichung ausgetrickst. [Internet]. pro-physik.de.
  • Makarov, Vadim; Skaar, Johannes; Lydersen, Lars Vincent Van de Wiel; Knight, Helen & Liu, Qin (2011). Quantum hackers: Cracking the uncrackable code. [Internet]. New Scientist.
  • Grepstad, Jon Olav; Kaspar, Peter; Due-Hansen, Jon; Johansen, Ib-Rune; Borch, Morten & Furuberg, Liv [Show all 9 contributors for this article] (2011). System for optical characterization of photonic crystal membranes - designed for biological sensing with single molecule sensitivity.
  • Grepstad, Jon Olav; Due-Hansen, Jon; Johansen, Ib-Rune; Borch, Morten; Kaspar, Peter & Furuberg, Liv [Show all 9 contributors for this article] (2011). Umiddelbar diagnose i 2020.
  • Grepstad, Jon Olav & Skaar, Johannes (2011). Does evanescent gain exist?
  • Lydersen, Lars Vincent Van de Wiel; Makarov, Vadim & Skaar, Johannes (2011). Comment on "Resilience of gated avalanche photodiodes against bright illumination attacks in quantum cryptography" [Appl. Phys. Lett. 98, 231104 (2011)]. Applied Physics Letters. ISSN 0003-6951. 99(19). doi: 10.1063/1.3658806.
  • Hågenvik, Hans Olaf & Skaar, Johannes (2019). Analysis of active and passive metamaterials. NTNU Grafisk senter. ISSN 978-82-326-3915-1.
  • Skaar, Johannes (2011). Elektromagnetisme. Tapir Akademisk Forlag.

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Published Sep. 3, 2019 8:21 AM - Last modified Apr. 22, 2023 10:12 PM

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