NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Mixed-Surfactants as a Novel Approach to Atomic Engineering of Spin Valves
Published
Author(s)
D X. Yang, H D. Chopra, P J. Chen, William F. Egelhoff Jr.
Abstract
Previously, surfactants in ultra-high vacuum have been used to obtain smooth interfaces in giant magnetoresistance effect (GMR) spin valves for an enhanced GMR. In the present study, a novel extension to the surfactant approach has been developed, called mixed surfactants . Instead of a single atomic species as a surfactant, mixed surfactant consists of two or more surfactant species. To test the idea of mixed surfactants, dc magnetron sputtered NiO/Co/Cu/Co bottom spin valves were studied with and without an equi-atomic alloy of Ag0.5Pb0.5 as a mixed surfactant. Results show that at Cu spacer thickness of 1.8 nm, the samples show a small or negligible GMR effect (0.5%) in surfactant-free samples. In contrast, spin valves with a 0.5 to 1.2 monolayer (ML) of surfactant AgPb deposited on the pinned Co layer exhibit more than 20-fold increase in GMR (10-11.5%). The given surfactant work best when deposited on the pinned Co layer. The use of mixed surfactants illustrates their efficacy in favorably altering the magnetic characteristics of GMR spin valves, and their potential use in other magnetoelectronics devices and multilayer systems.
Yang, D.
, Chopra, H.
, Chen, P.
and Egelhoff Jr., W.
(2021),
Mixed-Surfactants as a Novel Approach to Atomic Engineering of Spin Valves, IEEE Transactions on Magnetics
(Accessed October 13, 2025)