1 / 13

Coherent terahertz control of antiferromagnetic spin waves

Coherent terahertz control of antiferromagnetic spin waves. Ashida lab Mukai Noriyuki. contents. Introduction Spin flopping in picosecond timescale Sample - NiO : Magnetic Property experiment - Zeeman effect - THz-pomp NIR-probe - THz spin resonance

sarai
Télécharger la présentation

Coherent terahertz control of antiferromagnetic spin waves

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Coherent terahertz control of antiferromagnetic spin waves Ashida lab Mukai Noriyuki

  2. contents • Introduction • Spin flopping in picosecond timescale • Sample - NiO: Magnetic Property • experiment - Zeeman effect - THz-pomp NIR-probe - THz spin resonance - Coherent control of spin waves • summary • Future plan

  3. THz technology optics electronics AFMR:反強磁性共鳴 MO disc (Magneto-Optical disc) MD (Mini Disc)

  4. Spin flopping in picosecond timescale Gerrits et al., Nature 418, 509 (2002) Tsudosa et al. Nature428, 831-833(2004)

  5. Magnetic component of electromagnetic wave Ex. pulse energy =200μＪ pulse duration = 150 fs beam size = 100μm Calibrated Electric field = 100MV/cm Calibrated Magnetic field = 33 T

  6. NiO : Magnetic Property Neel temperature NaCl type crystal structure easy plane Spin direction Thickness AFM: antiferromagnetic (反強磁性体)

  7. Spin resonance-Zeeman effect- G: Zeeman torque γ: gyromagnetic constant S: spin of an electron B: magnetic field zeeman torque spin 周囲のスピンが同じ歳差運動をするとき、 巨視的に視ると磁化が歳差運動する

  8. THz-pump NIR-probe ファラデー回転が pomp光とprobe光の時間間隔Δtに依存

  9. THz spin resonance Faraday rotation θf ±0.1mrad(0.057degree) THz pump pulse Peak of magnetic field 0.13 T Peak of electric field 0.4 MV/ Harmonic oscillation with a period of 1ps (1THz)

  10. Coherent control of spin waves in ps-scale First pulse 6ps(6 cycles) later Second pulse 6.5ps(6.5cycles) later Second pulse

  11. Summary • the magnetic component of intense terahertz transients enables ultrafast controlof the spin degree of freedom. (1 picosecond scale)

  12. THz quarter wave plate Based parallel plates

  13. Future plan Faraday rotation Circular polarized THz-pomp Liner polarized THz-pomp NIR-probe

More Related