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• 12 décembre
  [Institut Quantique] Banque nationale
  12 décembre

  [Institut Quantique] Banque nationale

  Lieu : Description : Événement privé Lieu : Auditorium de l'IQ

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• 13 décembre
  [Séminaires] Séminaire de maîtrise de Bavneet Kaur
  13 décembre

  [Séminaires] Séminaire de maîtrise de Bavneet Kaur

  Lieu : Auditorium de l'Institut Quantique Description : Terahertz spectroscopy of thin metallic films and characteristicsof spintronic terahertz emitters.Spintronic terahertz emitters are broadbandand efficient sources of terahertz radiation, which emerged at the intersectionof ultrafast spintronics and terahertz photonics.  The spintronic emitter combines ultrabroadbandwidth, high efficiency, ease of use, and flexibility in terms of geometryand design. They are based on efficient spin-current generation,spin-to-charge-current conversion, and current-to electromagnetic radiation atterahertz frequencies.We have studied the efficiency of one ofsuch ultrabroadband terahertz spintronic emitters made of heterostructure ofmagnetic and heavy metals. We have used ultrafast laser spectroscopy techniquesto better understand the AC electrical characteristics of the individualultrathin films used to make the trilayer Pt/CoFeB/W heterostructure. Characterizationof the surface morphology of thin films and tri-layer devices has also beencarried out to establish a potential link between the efficiency of our spintronicemitters and the structural properties of the constituent materials. Theinfluence of the type of substrate (quartz or sapphire) on the crystallinequality, surface morphology and electrical properties of thin metallic filmswas also studied. Our results show that the performance of our spintronicemitters is superior to that of sources based on generation by opticalrectification in standard non-linear crystals (such as ZnTe). However, we havenot yet been able to fully assess the high-frequency bandwidth (> 4 THz) ofour emitters. [1]       T. Seifert et al., “Efficient metallic spintronicemitters of ultrabroadband terahertz radiation,” Nat. Photonics, vol.10, no. 7, pp. 483–488, Jul. 2016, doi: 10.1038/nphoton.2016.91.[2]       T. S. Seifert et al., “Terahertzspectroscopy for all-optical spintronic characterization of thespin-Hall-effect metals Pt, W and Cu 80 Ir 20,” J.Phys. Appl. Phys., vol. 51, no. 36, p. 364003, Sep. 2018, doi:10.1088/1361-6463/aad536.[3]       T. Seifert et al., “Terahertz SpinCurrents and Inverse Spin Hall Effect in Thin-Film Heterostructures ContainingComplex Magnetic Compounds,” SPIN, vol. 07, no. 03, p. 1740010, Sep.2017, doi: 10.1142/S2010324717400100.[4]       W. Fuscaldo et al., “Terahertzcharacterization of graphene conductivity via time-domain reflectionspectroscopy on metal-backed dielectric substrates,” J. Phys. Appl. Phys.,vol. 55, no. 36, p. 365101, Sep. 2022, doi: 10.1088/1361-6463/ac7759.Microsoft Teams meetingJoin on your computer, mobile app orroom deviceClickhere to join the meetingMeeting ID: 224 275 895 938  Passcode: h3Wxch DownloadTeams | Joinon the webJoin with a video conferencing deviceusherbrooke@m.webex.comVideo Conference ID: 113 382 379 5Alternate VTC instructionsUniversitéde SherbrookeLearnMore | Help| Meetingoptions | Legal

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• 13 décembre
  [Institut Quantique] Séminaire de maîtrise de Bavneet Kaur
  13 décembre

  [Institut Quantique] Séminaire de maîtrise de Bavneet Kaur

  Lieu : Auditorium de l'Institut Quantique Description : Lieu/Location : Auditorium de l'Institut QuantiqueTerahertz spectroscopy of thin metallic films and characteristicsof spintronic terahertz emitters.

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