| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances and Discoveries in Non-equilibrium Driven Nanomaterials and Thin Films
|
| Presentation Title |
Conversion of c-Si and a-Si to Q-Si phases by ion irradiation |
| Author(s) |
Siba Sundar Sahoo, Jagdish Narayan, Ambuj Tripathi, Roger Narayan |
| On-Site Speaker (Planned) |
Siba Sundar Sahoo |
| Abstract Scope |
Q-silicon, a new allotrope of zinc-blende silicon, was discovered by nanosecond laser annealing, where localized melting and ultrafast quenching allowed us to create atomically distinct structures of Q-phases. This new phase has a higher density (>60%) than crystalline silicon (c-Si) of zinc blende structure and shows robust room temperature ferromagnetism (Tc>400K). In the current work, we have established high energy ion bombardment of a-Si and c-Si can achieve similar quench rates to create Q-Si phases. The study uses ion - solid interaction simulations coupled with atomistic ab initio modeling to study the conversion methodology of a-Si to Q-Si. We carried out Raman spectroscopy to understand the bonding characteristics of the Q-Si, HAADF Z-contrast imaging to validate the densification of a-Si along the tracks. We also used ultrahigh energy resolution monochromated electron energy-loss spectroscopy (EELS) to detect and visualize the energy states near the Fermi level. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Nanotechnology, Characterization, Thin Films and Interfaces |