Engineering light induced phase change for emerging nanoscale processes

Introduction

Light-induced phase change (LPC) is the unifying theme underpinning many apparently non-related processes in:

1. Additive Manufacturing (AM) for metals where laser-induced vaporization and the formation of keyhole porosity is a major limiting factor for 3D printing.
2. Nanomedicine (NM) where laser-induced nanobubble dynamics and associated shockwave effects are powerful for malicious cell destruction.
3. Solar Energy (EN) where direct steam/vapor production from bulk and surface fluid is a promising technology for power and clean water solutions.

In addition to the challenging multiscale nature of phase change, LPC adds further complexities by introducing the multiphysics nature due to strong light-absorber interactions.

Objectives

We will tackle the fundamental challenge of the formation and control of LPC and develop a physics-based platform, supported by multiscale experimentation and multiscale simulation, as the tool to design and engineer LPC as an innovative mechanism for in situ process steering and control.

Work Programs

Five work programs are designed focusing on two complementary paradigms:

1. Fundamental Studies: Enhancing LPC mechanism understanding via developing physics-informed multiscale modeling validated by dedicated nanoscale experiments.
2. Application Studies: Engineering LPC for designed functions towards EN, NM, and AM respectively.

Expected Breakthroughs

Many breakthroughs beyond state-of-the-art work are expected, such as:

1. The establishment of a unique multi-physics and multiscale LPC simulation platform.
2. The revelation of LPC mechanisms by sub 100 nm experiments with localized temperature and nanobubble dynamics measurement.
3. The reverse engineering of LPC to maximize solar vapor production, inhibit keyhole pore formation, and control nanobubble shockwave effects.

Conclusion

The project will not only advance LPC understanding in the domain of Thermodynamics and Heat Transfer but also transfer the developed expertise into emerging applications.