講演情報
[17p-K102-2]Novel method for optical evaluation of persistent spin helix state in a GaAs/AlGaAs two-dimensional electron gas
〇Keito Kikuchi1, Jun Ishihara1, Miari Hiyama1, Sota Yamamoto1, Yuzo Ohno2, Makoto Kohda1,3,4,5 (1.Grad. Sch. of Eng., Tohoku Univ., 2.Univ. of Tsukuba, 3.CSIS, Tohoku Univ., 4.DEFS, Tohoku Univ., 5.QUARC, QST)
キーワード：
spin-orbit interaction、Persistent spin helix、Time-resolved Kerr rotation
We present a novel optical method for evaluating the persistent spin helix (PSH) state in a GaAs/AlGaAs quantum well. The PSH state, which forms when Rashba and Dresselhaus spin-orbit interactions (SOI) are equal, enables robust spin transport, making it promising for spintronic applications.Conventional SOI evaluation methods require sample processing and external magnetic fields, complicating measurements. To overcome this, we combine time-resolved Kerr rotation (TRKR) with a spatial light modulator (SLM). The SLM generates a spin helix with a controlled wavenumber, while the probe pulse measures spin dynamics. This method eliminates the need for spatial scanning and external fields, simplifying the setup.Experiments reveal that spin relaxation rates follow a parabolic dependence on wavenumber, allowing the extraction of SOI parameters and the spin diffusion coefficient. Our results provide a simple and effective alternative to conventional techniques.