Jiayi Zhu
My research is mainly on studying valley polarization controlling in different transition metal dichalcogenides (TMD) heterostructures and exploring TMD device structures with higher efficiency. Valley pseudospin is an analogy to spin, giving rise to a new quantum index for people’s manipulation and it has potential application in quantum computing in the future. 2D TMD is the most promising candidate material for useful valleytronic application from its strong excitonic effect and spin-valley locking properties. In TMD heterostructure, the strongly unbalanced valley polarization can be generated with circularly polarized light of minimal power. For example, in WSe2/MoSe2, people can use as low as a few nanowatt...
Chun-Chih Tseng
Introducing the magnetic and spin-orbit coupling into graphene in proximity to dissimilar crystals has been extensively studied to realize exotic emergent physics. They include the dissipationless edge transport in quantum anomalous Hall effect and the efficient spin accumulation due to exchange splitting of Dirac cone in graphene. My research will focus on the investigation of these proximity effects in graphene on van der Waal magnets and topological insulators by the transport characterization. This study will help to gain the better understanding in engineering graphene properties and might benefit the low energy consumption application in the future Advisor: Matthew Yankowitz - Physics...
Rachel Tenney
I am studying perovskite-type chromium compounds that show intrinsic two-dimensional magnetism and exhibit unique absorption properties for applications including magnetic storage, spintronics, quantum computing, and magnetic switching. My project involves the synthesis of the hybrid organic/inorganic compounds, post-synthetic modification of these compounds through anion exchange, optical measurements that focus on variable-temperature absorption, and exfoliation with the goal of building novel heterostructures. Advisor: Daniel Gamelin - Chemistry...
Dan Sturm
My research focuses on mitigating the rapidly growing energy cost of artificial intelligence computation by developing a new ultra-low power compute approach using photonic integrated circuits (PICs). PICs - microchips that let light flow instead of electricity - have become increasingly popular since light can carry higher data bandwidths while consuming far less power. As a result, they offer a promising path towards powerful but energy-efficient AI accelerators. We minimize energy consumption by using programmable phase change material that can store data on-chip at zero energy, and organize PCM-based compute cells in a specialized architecture (systolic array) for efficient data reuse. In the past...
Thom Snoeren
It is predicted that by 2030 more than 20% of the global electricity demand will come from computing, urging the transition to next-generation, energy-efficient quantum computing technologies. This will require development of novel materials with enhanced magnetic and electrical control. The ferromagnetic 2D-layered Van der Waals material CrI3 is one of the most promising materials for spintronics and can readily be integrated into layered circuits. However, investigations on the optical properties of CrI3 are severely lacking. My research will focus both on incorporating carefully designed atomic defects such as lanthanides, as well as characterizing and iteratively optimizing the system using optical spectroscopy techniques. The goal is...
Gillian Shen
My research involves the design, fabrication, and optimization of quantum dot light-emitting diodes (QLEDs) for next-generation lighting and displays. As lighting accounts for 15% of global electricity consumption, advances in the energy efficiencies of lighting technologies would be a significant step towards reducing our global energy footprint. Mechanistic understandings of the excited state dynamics in quantum dots for QLEDs will also enable simultaneous advancements in quantum dot photovoltaic devices for more efficient solar cells. The first aspect of my work involves the synthesis of perovskite quantum dots with carefully controlled synthetic parameters and post-synthetic treatments for the growth of monodisperse, defect passivated, and highly...
Sage Scheiwiller
Blends of conjugated and commodity polymers provide a way to balance desirable electronic properties and physical properties of both components. This balance plays a critical role in the development and performance of organic electronic devices such as photovoltaics (OPVs), field-effect transistors (OFETs), bioelectronics, and wearable sensors. Understanding the fundamental interactions between the conjugated polymers and matrix polymers at all stages of processing is essential for designing and optimizing organic electronic devices. My research focuses on understanding the structure property relationship in solid and solution states in order to track how the pressures of processing and composition change the morphology and the film properties. Advisor: Lilo...
Michael Riehs
My research involves using concepts and techniques from molecular inorganic chemistry to alter the properties of two-dimensional materials for use in catalysis. Specifically, I am working on functionalizing semiconducting black phosphorus with transition metals that can serve as active sites for reactions such as hydroformylation. Synthesis of this type of material from the bulk down to a single atomic layer can provide insight into metal support interactions that often dictate how a catalyst behaves. Advisor: Alexandra Velian – Chemistry...
Meredith Pomfret
Rigid rod polymers are a class of high-performance materials made up of a conjugated, heteroaromatic backbone that have applications spanning engineering and electronics. Unfortunately, due to their chain stiffness, thermal recycling and solution-state processing of these materials can be very difficult. My research is focused on incorporating the ‘shape shifting’ small molecule bullvalene into rigid rod polymer chains to modulate the polymer physical properties while maintaining the desired thermal and chemical stability. Bullvalene undergoes rapid Cope rearrangements at room temperature to access 1.2 million degenerate isomers. Within a polymer chain, bullvalene leads to a dense, coiled chain conformation due to an ensemble of different...
Heonjoon Park
Two-dimensional semiconductor moiré superlattices are a powerful platform for engineering correlated electronic phenomena. My research focuses on the exploration of the extended Bose-Hubbard model of exciton lattices in twisted transition metal dichalcogenide moiré materials. I employ optical techniques to probe emergent phases in interacting opto-moiré quantum matter. Advisor: Xiaodong Xu - Physics...
Emily Nishiwaki
Alcohols are energy-dense fuels and small-chemical building blocks for electrosyntheses of commodity chemicals and fuels. Developing earth-abundant alternatives, such as nickel, to noble metals as catalysts for alcohol electro-oxidation is a critical step towards global sustainability. Nickel-based materials catalyze this reaction by forming a layer of NiOOH (in alkaline conditions) that assists in the rate-limiting deprotonation step of the alcohol on a surface. My research involves synthesizing a series of Ni-based nanocrystals (Ni2P, Ni3S2, Ni3B, etc) and exploring how the incorporation of additional non-metals modulates surface energetics. Additionally, I will be investigating how the oxy-hydroxide layer forms on different nanocrystals and ultimately impacts activity...