Terahertz Generation via Picosecond Spin-to-Charge Conversion in IrMn3/Ni−Fe Heterojunction

Abstract

† Cheng Li, Bin Fang and Like Zhang contributed equally to this work. nanoseconds, which cannot support applications in the ter-44 ahertz field. To tackle this issue, the approach of applying 45 a femtosecond laser pulse in a specifically designed mag-46 netic heterostructure [18] is proposed, which reduces the 47 timescale of spin-electricity conversion to the subpicosec-48 ond range, enabling the engineering of terahertz spintronic 49 devices. Therefore, this holds out the promise of spin-50 tronic terahertz emitters. In this respect, emerging terahertz 51 devices comprised of a variety of nonmagnetic materials 52 or interfaces, such as heavy metal [19-24], topological 53 insulator [25-28], and Ag/Bi Rashba interface [29,30], 54 have been validated. Apart from that, by using the afore-55 mentioned spin-to-charge conversion of antiferromagnetic 56 materials, Chen et al. proposed a compensated magnetic 57 heterostructure consisting of ferrimagnet and antiferro-58 magnet to operate as a terahertz emitter [31]. Mean-59 while, Zhou et al. observed terahertz emission in a non-60 collinear antiferromagnetic Mn 3 Sn heterostructure [32], 61 which extends the material selection for spintronic tera-62 hertz emitters. Nevertheless, neither detailed experimental 63 analysis nor quantitative calculation is explicitly presented 64 2331-7019/21/0(0)/XXXXXX(7) XXXXXX-1

Spintronics Based Terahertz Sources

“…The trend of THz amplitudes with respect to NM materials is in good agreement with the calculated spin-Hall conductivity. Related works [52][53][54][55][56] also studied NM materials, such as Au, Ru, Al, IrMn 3 , and Mn 2 Au. At present, Pt is still the best choice for preparing NM layers, owing to the lesser effect on the THz amplitude for STEs.…”

Simulations of magnetization reversal in FM/AFM bilayers with THz frequency pulses

“…More Recently, it has been shown Mn 2 Au can be coupled ferromagnetically at the interface to Permalloy with one-to-one imprinting of the AFM order on the FM domains 10 , though little is known of the switching dynamics and whether one can simultaneously take advantage of the higher frequency dynamics of the AFM whilst being coupled to the sluggish FM. While AFM/FM bilayer systems have remained largely unexplored for reversal applications, Efforts have already been made to develop and understand the use of FM/AFM bilayers as THz emittors 23 – 25 .…”

Noncollinear Antiferromagnetic Spintronics

“…For example, it has been shown that Mn 3 Sn and Mn 3 Ir can be unutilized to construct THz emitters. [114,115] In addition, the large AHE signals have been shown to survive at a THz frequency at room temperature, which is beneficial for THz information reading (Fig. 5).…”