TY  - JOUR
AU  - Seifert, T.
AU  - Jaiswal, S.
AU  - Martens, U.
AU  - Hannegan, J.
AU  - Braun, L.
AU  - Maldonado, P.
AU  - Freimuth, Frank
AU  - Kronenberg, A.
AU  - Henrizi, J.
AU  - Radu, I.
AU  - Beaurepaire, E.
AU  - Mokrousov, Y.
AU  - Oppeneer, P. M.
AU  - Jourdan, M.
AU  - Jakob, G.
AU  - Turchinovich, D.
AU  - Hayden, L. M.
AU  - Wolf, M.
AU  - Münzenberg, M.
AU  - Kläui, M.
AU  - Kampfrath, T.
TI  - Efficient metallic spintronic emitters of ultrabroadband terahertz radiation
JO  - Nature photonics
VL  - 10
SN  - 1749-4893
CY  - London [u.a.]
PB  - Nature Publ. Group
M1  - FZJ-2016-02625
SP  - 483–488
PY  - 2016
AB  - Terahertz electromagnetic radiation is extremely useful for numerous applications, including imaging and spectroscopy. It is thus highly desirable to have an efficient table-top emitter covering the 1–30 THz window that is driven by a low-cost, low-power femtosecond laser oscillator. So far, all solid-state emitters solely exploit physics related to the electron charge and deliver emission spectra with substantial gaps. Here, we take advantage of the electron spin to realize a conceptually new terahertz source that relies on three tailored fundamental spintronic and photonic phenomena in magnetic metal multilayers: ultrafast photoinduced spin currents, the inverse spin-Hall effect and a broadband Fabry–Pérot resonance. Guided by an analytical model, this spintronic route offers unique possibilities for systematic optimization. We find that a 5.8-nm-thick W/CoFeB/Pt trilayer generates ultrashort pulses fully covering the 1–30 THz range. Our novel source outperforms laser-oscillator-driven emitters such as ZnTe(110) crystals in terms of bandwidth, terahertz field amplitude, flexibility, scalability and cost.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000378839600015
DO  - DOI:10.1038/nphoton.2016.91
UR  - https://juser.fz-juelich.de/record/809696
ER  -