Rajeswari Jayaraman, postdoc in Fabrizio Carbone’s group, is one of the six researchers from EPFL who have been awarded the prestigious Ambizione grants this year. With her Ambizione grant, she will investigate “Real time magnon dynamics for next generation magnonic devices”. Future generations of memory devices can benefit from such spin-based (magnon) data processing. A variety of magnonic crystals – periodically modulated magnets on the quantum scale – will be explored in this project. The art here is, not only to control the energy but also the behaviors in the ultrafast time domain in one experimental probe.
To unravel the energetic and temporal quantum properties of such spin textures, Rajeswari is developing a time-of-flight (ToF) Electron Energy Loss Spectrometer (EELS) and combines with the state-of-the-art ultrafast electron diffraction (UED) set-up in Carbone’s group. This unique marriage of techniques will provide the dynamics of magnons with combined energy and temporal resolution. The project aims to unravel the evolution and relaxation dynamics of magnons in novel and emerging metamaterials.
In addition, the THz generation capability in our UED set up will allow to resonantly photoexcite the material to drive specific phonons and phonon-assisted magnons. In this way, one can induce exciting structural or electronic modes that can be traced with picoseconds resolution by diffraction of the electron pulses. Such experiments will ultimately allow us to achieve a unique microscopic control of magnetism with tailored ultra-short light pulses.