Enhanced THz emission from spintronic emitters with Pt-Al alloys

F Felix Janus (New Materials Electronics Group, Department of Electrical Engineering and Information Technology, Technical University of Darmstadt 1 , Merckstr. 25, 64283 Darmstadt,) N Nicolas S. Beermann (Fakultät für Physik, Universität Bielefeld 2 , Universitätsstraße 25, 33615 Bielefeld,) A Amir Khan J Jyoti Yadav R Reshma Rajeev Lekha (New Materials Electronics Group, Department of Electrical Engineering and Information Technology, Technical University of Darmstadt 1 , Merckstr. 25, 64283 Darmstadt,) W Wentao Zhang H Hassan A. Hafez (Fakultät für Physik, Universität Bielefeld 1 , 33615 Bielefeld,) D Dmitry Turchinovich (Fakultät für Physik, Universität Bielefeld 1 , 33615 Bielefeld,) M Markus Meinert (New Materials Electronics Group, Department of Electrical Engineering and Information Technology, Technical University of Darmstadt 1 , Merckstr. 25, 64283 Darmstadt,)

Abstract

Platinum (Pt) is the element with the largest spin Hall conductivity and is known as the most efficient spin-to-charge conversion material in spintronic THz emitters. By alloying with aluminum (Al), its resistivity can be substantially increased, exceeding 100 μΩ cm. While the spin Hall conductivity is reduced by alloying, the relative resistivity increase surpasses the reduction of spin Hall conductivity, thereby enhances the spin Hall angle. We make use of this mechanism to improve the commonly used Pt-based spintronic THz emitter and demonstrate that an increase of 67% in the THz emission amplitude can be achieved between 20% and 30% Al in Pt. We show that the enhanced THz emission amplitude is driven by the enhanced multilayer impedance due to the larger resistivity.

Article Details

Volume / Issue Vol. 127, Issue 15
Published October 13, 2025
ISSN 0003-6951
Publisher American Institute of Physics

Journal Info

Applied Physics Letters

American Institute of Physics

ISSN: 0003-6951 Physical Sciences

Authors (9)

F

Felix Janus

New Materials Electronics Group, Department of Electrical Engineering and Information Technology, Technical University of Darmstadt 1 , Merckstr. 25, 64283 Darmstadt,

N

Nicolas S. Beermann

Fakultät für Physik, Universität Bielefeld 2 , Universitätsstraße 25, 33615 Bielefeld,

A

Amir Khan

J

Jyoti Yadav

R

Reshma Rajeev Lekha

New Materials Electronics Group, Department of Electrical Engineering and Information Technology, Technical University of Darmstadt 1 , Merckstr. 25, 64283 Darmstadt,

W

Wentao Zhang

H

Hassan A. Hafez

Fakultät für Physik, Universität Bielefeld 1 , 33615 Bielefeld,

D

Dmitry Turchinovich

Fakultät für Physik, Universität Bielefeld 1 , 33615 Bielefeld,

M

Markus Meinert

New Materials Electronics Group, Department of Electrical Engineering and Information Technology, Technical University of Darmstadt 1 , Merckstr. 25, 64283 Darmstadt,