Funded Projects

The Maryland Quantum-Thermodynamics Hub aims to serve as a lodestone for quantum-thermodynamics research in North America, as part of an international network.

(opens in a new window)For more information see the project website.

Bioinspired hardware offers a pathway to energy-efficient and adaptable technologies with advanced functionality. Furthermore, nanoscale components offer not just extreme  miniaturization, but also a quantum advantage beyond classical capabilities. For these reasons, magnetic tunnel junctions (MTJs) have attracted considerable attention as candidates for next-generation, high-density, non-volatile memory. A prominent and urgent need for this technology arises in machine learning, whose use in real-world applications has exploded recently. However, the massive computing resources and energy requirements to e.g. train neural networks using standard CMOS technology is a major limitation. Devices utilizing MTJs may solve these problems, because they provide embedded memory in unconventional circuits, escaping the speed/power bottlenecks arising when memory and processors are separated. Furthermore, MTJs exhibit resistive switching behaviour that closely mimics biological neurons, meaning they can be used directly as functional components in neuromorphic hardware for machine learning applications. Such devices are fast, highly efficient, and operate at very low power by exploiting inherently quantum mechanical effects. In this project we will use advanced computational techniques to model and simulate the quantum dynamics of correlated materials and heterostructures providing insight into MTJ systems, taking into account material-specific properties as well as electron interactions and interfacial magnetism. 

Coming soon.

The aim of this project is to identify the most thermodynamically efficient model for quantum computation. By quantitatively assessing the energy requirements for the coherent control of quantum systems, and by taking into account unavoidable environmental spoiling effects. 

(opens in a new window)For more information see the project website.

Quantum condensed matter systems display an incredibly diverse range of physical behavior, due to the complex collective properties that emerge when a large number of quantum degrees of freedom interact. This project lies at the intersection between two pillars of modern physics: the quantum many body problem arising due to strong electronic interactions in condensed matter systems, and topological quantum matter arising due to nontrivial properties of solid state band structures. We first examine generalized SSH models, and then study with DMFT an interacting version on an SSH-Bethe lattice. We then develop the auxiliary field approach to reformulate the interacting problem in terms of an equivalent non-interacting system living in a larger Hilbert space. We show that the Mott metal-insulator transition in the Hubbard model can be understood as a topological quantum phase transition with domain wall dissociation. 

Semiconductor quantum dot devices offer a highly tunable platform to study the strongly correlated electron physics at the nanoscale. Quantum circuits built from quantum dots allow us to realize fundamental models of quantum matter and exhibit a wide range of behavior. A new paradigm has recently emerged, in which hybrid metal-semiconductor components can be incorporated into circuits. This has enabled new interactions to be engineered, and exotic quantum critical physics to be studied. In this project we develop models and methods to treat complex quantum impurity models describing such quantum devices. We focus on accurate simulation using numerical renormalization group techniques, and the development of new quantum transport calculations for such systems.

When nanoscale components are incorporated into electronic circuits, the laws of quantum mechanics govern their basic properties. Striking phenomena appear, such as entanglement and quantum interference, and have no classical analogue. The next generation of miniaturized electronics will overcome the limitations of traditional design paradigms by exploiting the novel functionality of the nano. The ultimate nanoelectronics building block -- from which to build quantum devices with advanced functionality, sensitivity, and energy efficiency -- is arguably the single-molecule transistor. In addition to embodying the extreme limit of component miniaturization, molecular electronics could utilize the incredible variety of different molecules provided by nature, exploiting their robust and reproducible chemical complexity. But what new physics can be realized in single-molecule devices, and how can this be harnessed for novel functionality? Which molecules best fulfill this function? To realize the central goal of rational device design, we will formulate a theoretical framework for understanding single-molecule transistors, and develop computational tools for accurate simulation. We will focus on the complex interplay between quantum interference due to competing transport pathways through a molecule, and entanglement from electronic interactions.