Engineering of spin-lattice relaxation dynamics by digital growth of diluted magnetic semiconductor CdMnTe

TL;DR

This paper demonstrates that digital alloying via molecular-beam epitaxy effectively accelerates spin-lattice relaxation in CdMnTe semiconductors without affecting static magnetization, enabling new spin engineering possibilities.

Contribution

It introduces a novel approach to tailor magnetic relaxation dynamics in diluted magnetic semiconductors using digital alloying techniques.

Findings

Spin-lattice relaxation is accelerated by an order of magnitude.

Static magnetization remains unaffected by digital alloying.

Magnetization dynamics are highly sensitive to Mn ion clustering.

Abstract

The technological concept of "digital alloying" offered by molecular-beam epitaxy is demonstrated to be a very effective tool for tailoring static and dynamic magnetic properties of diluted magnetic semiconductors. Compared to common "disordered alloys" with the same Mn concentration, the spin-lattice relaxation dynamics of magnetic Mn ions has been accelerated by an order of magnitude in (Cd,Mn)Te digital alloys, without any noticeable change in the giant Zeeman spin splitting of excitonic states, i.e. without effect on the static magnetization. The strong sensitivity of the magnetization dynamics to clustering of the Mn ions opens a new degree of freedom for spin engineering.