Femtosecond-laser-induced spin-polarized electron emission from a GaAs tip

Authors

Evan M. Brunkow, University of Nebraska - LincolnFollow
Eric R. Jones, University of Nebraska-LincolnFollow
Herman Batelaan, University of Nebraska - LincolnFollow
Timothy J. Gay, University of Nebraska - LincolnFollow

ORCID IDs

Evan Brunkow https://orcid.org/0000-0002-1123-3382

Eric R. Jones https://orcid.org/0000-0001-8479-3527

Herman Batelaan https://orcid.org/0000-0003-3175-8095

T. J. Gay https://orcid.org/0000-0003-3175-8095

Date of this Version

2-2019

Citation

Appl. Phys. Lett. 114, 073502 (2019)

doi.org/10.1063/1.5070059

Comments

Published under license by AIP Publishing. Used by permission.

Abstract

It is shown that focusing circularly polarized 800nm light pulses of duration 100 fs on the tips of p-GaAs crystalline shards having no negative electron affinity (NEA) activation results in electron emission that is both fast and spin-polarized. The 400 fs duration of the emission process was determined by pump/probe measurements. The three samples we investigated produced electron polarizations of 13.1(0.9)%, 13.3(0.7)%, and 10.4(0.2)%. Emission currents ranged between 50 pA and 3 nA with a sample bias of –100 V and an average laser power of 100 mW. The electron emission exhibited linear dichroism and was obtained under moderate vacuum conditions, similar to that of metallic tips. This source of spin-polarized electron pulses is “fast” in the sense that the electron emission process is of comparable duration to the laser pulses that initiate it.