Spintronic terahertz-frequency nonlinear emitter based on the canted antiferromagnet-platinum bilayers

Abstract

Note: This paper is part of the Special Topic section "Advances in Terahertz Solid-State Physics and Devices" published in J. Appl. Phys. 125(15) (2019).

Terahertz Spin Current Dynamics in Antiferromagnetic Hematite

“…We, thus, ascribe the generation of J s y to ultrafast spin pumping launched by the laserinduced transient magnetization ΔM(t). [26,27,46,47] The dynamic ΔM(t) originates from an effective magnetic field that is induced by the optical field through an ISRS process, as observed in AFMs previously. [48][49][50] An off-resonant and coherent ISRS response is expected to sensitively depend on the pump polarization and is, thus, tested by studying the impact of the pump polarization on J s y .…”

“…We, thus, ascribe the generation of $${\bm{J}}_{y}^{\mathrm{s}}$$ to ultrafast spin pumping launched by the laser‐induced transient magnetization Δ M ( t ). [ 26,27,46,47 ] The dynamic Δ M ( t ) originates from an effective magnetic field that is induced by the optical field through an ISRS process, as observed in AFMs previously. [ 48–50 ]…”

Strongly nonlinear antiferromagnetic dynamics in high magnetic fields

“…In addition, non-monotonous behavior of the spin-pumping into the adjacent Pt layer is observed, explained by the counter-acting frequency shifts resulting from the large amplitude and from the applied magnetic field. We believe that our results will be useful for the development of theoretical description of nonlinear AFM behavior, which may result in tunable and highly sensitive THz-frequency AFM devices such as detectors [16], emitters [17] and spectrum analyzers [18].…”

Electrical detection of the spin reorientation transition in antiferromagnetic TmFeO$_3$ thin films by spin Hall magnetoresistance

“…Antiferromagnets (AFMs) are a key focus of current spintronic research [1][2][3]. Due to their fast spin dynamics and stability against external perturbations, AFMs are promising candidates for THz emitters [4,5] and next generation data storage devices [6]. The insulating canted antiferromagnet TmFeO 3 (TFO) has recently gathered significant interest because of the possibility to coherently switch its spin state by 90 • with a THz pulse [7] in the proximity of the temperature-driven spin reorientation transition (SRT) in bulk single crystals.…”