Research

Our research aims to: 1) design and grow new materials and structures to dramatically enhance light-matter interactions for applications in energy conversion, optoelectronics and information science; 2) explore the fundamental, ultrafast excited-state dynamics and flow of energy in functional materials and their assemblies; 3) optically manipulate the non-equilibrium vibrational & electronic degrees of freedom for understanding and achieving new functionalities in emerging materials. We collaborate extensively with groups at Yale University and elsewhere. Our efforts encompass the following areas.

Nanostructured materials growth and design

We harvest both solution-based synthesis and vapor-phase growth techniques to fabricate thin-film and nanostructured materials. These materials and structures are exploited for energy conversion, optoelectronics, sensing, and information science applications. We are particularly interested in layered hybrid organic-inorganic perovskites and other classes of low-dimensional materials.

Relevant publications: Nature Communications, 2018, 9, 2019; Physical Review Letters, 2018, 121, 127401

Excited-state dynamics and flow of energy

We investigate the dynamic processes of fundamental excitations (e.g., electrons, lattice vibrations) in solid-state and solution-phase materials using time-resolved optical spectroscopy. Our spectroscopic setup covers a wide spectral range (250 nm ~ 15 ┬Ám) with ~100 fs time resolution and diffraction-limited spatial resolution.

Relevant publications: Nature Communications, 2018, 9, 2792; Nature Photonics, 2016, 10, 267-273

Optical manipulation of materials

We use femtosecond laser pulses as an active tuning knob to probe elusive structure-property relationships in emerging materials and control their properties out of equilibrium. To this end, we combine ultrafast excitation (electronic or vibrational) with time-resolved absorption, luminescence and Raman measurements of materials at controlled environments. Our optical setups are flexible, well integrated, and routinely modified to engage with different measurements.

Relevant publications: Nature Communications, 2019, 10, 482; Nature Communications, 2016, 7, 12892; Advanced Functional Materials, 2020, 30, 1907982