ANNLab Research
Graphene Nanoribbon Transistors
Building the Next Generation of Computing Hardware
The chips that power our phones, laptops, and data centers are all built on silicon. Silicon has served us well for decades, but we are reaching the point where we simply cannot make silicon transistors much smaller or more efficient. At the same time, artificial intelligence (AI) is driving an enormous demand for computing power, and the energy costs of running AI workloads keep climbing. We need something new. Our research focuses on graphene nanoribbons (GNRs), extremely narrow strips of carbon atoms arranged in a honeycomb pattern. What makes GNRs special is that they are built from the bottom up, atom by atom, using chemical reactions on surfaces. This gives us a level of precision that traditional manufacturing methods cannot match. The resulting ribbons are only a few atoms wide, and their electronic properties can be tuned by changing their width and edge structure. GNRs can carry electrical current very efficiently and have the right kind of electronic behavior to work as transistor channels, the core switching elements inside a computer chip. We are working on improving how electrical contacts are made to these tiny ribbons, how to protect them with insulating layers, and how to scale up the fabrication process so that GNR-based devices can eventually be produced on full-size wafers. The goal is to build transistors that are faster, smaller, and use less energy than what silicon can offer today.
Topological Acoustic Wave Devices
Robust Signal Processing for Next-Generation Wireless
As wireless communication moves toward 6G and beyond, the devices that process radio-frequency (RF) signals need to become more precise, more efficient, and more resilient. Surface acoustic wave (SAW) devices, which use sound waves traveling along the surface of a crystal, are already widely used in filters and sensors. But conventional designs can be sensitive to manufacturing imperfections and structural defects. We are exploring a different approach, drawing on ideas from topological physics. In simple terms, topological protection means that the wave propagation is inherently robust, small defects or variations in the structure do not disrupt the signal. We build these devices on piezoelectric substrates like lithium niobate, using carefully designed electrode patterns and periodic structures to control how sound waves move through the material. The result is a new class of acoustic devices that can filter and route signals with low loss and high selectivity. We are particularly interested in making these platforms reconfigurable, so they can adapt their behavior based on real-time conditions, a feature that could be valuable for AI-driven communication systems and intelligent sensing applications.
Semiconducting Behavior of Chalcopyrite
Connecting Semiconductor Physics to Sustainable Mining
Chalcopyrite is the most common copper-bearing mineral on Earth, and copper is essential for everything from electrical wiring to renewable energy systems. The problem is that chalcopyrite is notoriously difficult to dissolve and extract copper from, which makes mining less efficient and more environmentally costly. What many people do not realize is that chalcopyrite is also a semiconductor, it conducts electricity in ways that depend on its composition, defects, and crystal structure. We believe that understanding these electronic properties is key to figuring out why some chalcopyrite samples leach easily while others resist dissolution. In our lab, we measure the electrical transport properties of chalcopyrite samples from different geological sources. Using Hall effect measurements, we determine things like how many charge carriers are present, how fast they move, and what type of conduction dominates. We then connect these findings to the mineral's microstructure and chemical makeup. The hope is that this semiconductor-level understanding will lead to smarter, more targeted approaches to copper extraction, reducing waste and energy use in the process.
Emerging Ideas & Out-of-the-Box Science
Exploring New Directions at the Boundaries of What We Know
Beyond our main research programs, we also explore early-stage ideas that do not yet fit neatly into established research directions. Some of these efforts originate from unexpected experimental observations, while others emerge when we recognize connections between fields that are rarely in conversation with one another. We intentionally keep these explorations open and flexible. When an idea begins to show promise, through initial results, new collaborations, or emerging applications, it can evolve into a focused research direction and eventually grow into a full research program.