Photo Controlled Magnetic Properties of van der Waals Layered Materials

Nontechnical:

The recent discovery of quantum magnets in the post-silicon era offers the possibility of novel applications in computing, database storage, and communications. To realize these applications, tuning the magnetic properties of these materials is an ultimate goal of physics and materials science research. A rapidly evolving research area, controlling and manipulating the magnetic properties of quantum magnets using light, has just begun.

The goal of this project is to use external light as a control parameter to drive quantum magnetic phases, to advance our knowledge and understanding, and to control the emergent phases. In this project, photoexcitation across broad time-scales (seconds to femtoseconds) is used to control and manipulate the magnetic properties of these new classes of materials.

Outreach activities train army personnel and veterans at Fort Bliss and White Sands Missile Range in the El Paso region. This project further provides research and peer-coaching opportunities as well as professional development seminars to further foster education in STEM fields in UTEP, which is predominantly (81%) a Hispanic serving institute.

Technical:

Newly discovered (quasi) two-dimensional (2D) van der Waals (vdW) magnets show unexpected magnetic properties (monolayer ferromagnetism, giant second harmonic generation, etc.,) associated with the reduced dimension, which has generated a great deal of excitement in the recent past. Previous works have shown that electric field, electrostatic doping, external pressure, and mixed halide chemistry can control the magnetic properties of these materials.

Unlike the above approaches, ultrafast photoexcitation is known to control and manipulate the magnetic properties of materials much more rapidly and effectively which allows developing light controlled spin electronics. Previous researchers have measured the magnetic properties of these layered materials using light. However, controlling and manipulating their magnetic properties using light has largely been unexplored.

The main objective of this research is to establish a comprehensive fundamental scientific knowledge and understanding in controlling and manipulating the magnetic behavior of vdW materials upon photoexcitation. Of specific importance, the two main goals of this combined experimental and theoretical effort are to (a) study the magnetic properties in quasi-2D and 2D CrX3 upon photoexcitation, and to (b) gain in-depth understanding on magnetic exchange interactions and 2D correlations near magnetic order in quasi-2D CrX3 alter upon photoexcitation.

This effort has the potential to be extended to other emerging vdW magnetic metals, both at the quasi-2D and true 2D limit. This project provides research and educational opportunities for Hispanic students, army personnel and veterans at Fort Bliss and White Sands Missile Range in the El Paso region.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.