MSE Department Seminar

Voltage imaging provides unparalleled spatial and temporal resolution of the brain’s electrical signaling at the cellular and circuit levels. A longstanding challenge has been to develop genetically encoded voltage sensors to track membrane voltage from multiple neurons in behaving animals. However, brightness and signal to noise ratio have limited the utility of existing voltage sensors, especially in vivo.

Dynamic materials comprising of soft solids and structured liquids that can adapt to surrounding environment are poised to be key components of future technologies. They offer the unique opportunity couple changes in their mechanical confirmation to physical properties and function via their micro and nano scale architecture. However, soft and fluid materials are seldom used for optical engineering.

Solid-state batteries pose new challenges to the battery design due to the unique solid-solid interfaces at battery cathode and anode. However, these interfaces, upon critical understanding and design, also form a special opportunity to unlock advanced battery performances. We design solid state batteries based on our unique mechanical constriction principle and the constrained ensemble computational platform, for a stable cycling toward performance relevant conditions.

Programmable shape-shifting materials can take different physical forms to achieve multifunctionality in a dynamic and controllable manner. We take geometry from nano- to macroscales by (re)programming anisotropy in liquid crystal elastomers (LCEs) and their nanocomposites in the forms of films, fibers, and droplets. Through inverse engineering, that is pre-programming inhomogeneous local deformations in LCEs, we show shape morphing into arbitrary 3D shapes. By incorporating 1D and 2D nanomaterials (e.g.

We address the problem of learning of classical Markov Random Fields that are widely used in material science, statistical physics, and computer science to represent structured Gibbs distributions. We introduce a new computationally efficient Interaction Screening method for learning discrete and continuous Gibbs distributions for which maximum likelihood approaches are intractable. The algorithm recovers the structure and parameters of the Hamiltonians with multi-body interactions specified in an arbitrary basis.

100 years since the discovery of ferroelectricity, this phenomenon still remains a center of intense research. The electrically switchable polarization, which is strongly coupled to the physical properties of ferroelectrics, determines the multifunctional nature of their responses to the external stimuli and underpins our ability to address a range of technological applications related to future computing.

The emergence of the two-dimensional (2D) transition metal dichalcogenides (TMDCs) ushers in a new chapter in excitonic physics. In monolayer TMDCs, the reduced screening enhances the Coulomb interaction and gives rise to strongly bound excitons with the binding energy of hundreds of meV. In addition, the valley degree of the freedom of the exciton is robust and can be accessed through chiral light. For the past few years, we have advanced our understanding of the valley contrasting excitonic physics in monolayer WSe₂ and associated van der Waals (vdW) heterostructures.