Peter Qiang Liu (University at Buffalo)

Date: Mon. November 18th, 2024, 12:45 pm-1:45 pm
Location: Foldy Room (Rockefeller 221)
Website: http://ubwp.buffalo.edu/mtpoetlab/

Transforming the Landscape of Photonics with Liquid Metals

Metals are widely used in various electronic and photonic devices for different purposes. Conventional
metals such as gold, aluminum and copper are all solid metals, which lack structural reconfigurability and
are prone to structural damage upon repeated deformation such as bending and stretching. In recent years,
room temperature liquid metals including gallium and gallium-rich alloys have been exploited to develop
soft, stretchable and reconfigurable electronics. The rising tide of liquid metals is also lifting the
photonics boat and ushering in new possibilities. Liquid metals have been utilized to realize
reconfigurable RF antennas and plasmonic structures in the visible and UV spectral regions, which led to
a variety of applications [1].

In my talk, I will discuss our recent explorations of using liquid metals to form photonic structures and
devices for different spectral regions and a variety of applications. I will first focus on our demonstration
of an unconventional type of nanophotonic sensors which exploits the fluidity and conformability of
liquid metals to effectively overcome the fundamental trade-off between field confinement/enhancement
and analyte delivery efficiency, i.e., the bottleneck that limits the performance of many conventional
nanophotonic sensors. These liquid-metal-based nanophotonic sensors achieved significantly improved
performance for surface-enhanced infrared absorption (SEIRA) [2] and surface-enhanced Raman
scattering (SERS) sensing [3]. I will then discuss our development of a facile and reliable technique to
deterministically pattern liquid-metal-based nanoscale structures with precisely defined shapes, sizes and
spatial distributions [4], which may lead to a range of nanophotonics and plasmonics applications,
especially for the UV spectral region. Last but not least, I will present some early results of our
development of electro-chemically driven reconfigurable liquid metal photonic structures.

[1] P.Q. Liu, X. Miao, S. Datta, “Recent Advances in Liquid Metal Photonics: Technologies and
Applications”, Optical Materials Express 13, 699 (2023).
[2] X. Miao, T.S. Luk, P.Q. Liu, “Liquid-metal-based nanophotonic structures for high-performance
SEIRA sensing”, Advanced Materials 34, 2107950 (2022).
[3] S. Datta, S. Vasini, X. Miao, P.Q. Liu, “Surface-Enhanced Raman Scattering Sensors Employing a
Nanoparticle-On-Liquid-Mirror (NPoLM) Architecture”, Small Methods 8, 2400119 (2024).
[4] M.A.K. Khan, Y. Zhao, S. Datta, P. Paul, S. Vasini, T. Thundat, P.Q. Liu, "Deterministic Fabrication
of Liquid Metal Nanopatterns for Nanophotonics Applications", Small, 2403722 (2024).

 

Host: Lydia Kisley