Quantum Thermodynamics Hub
|PIs||Christopher Jarzynski, Nicole Yunger Halpern, Sebastian Deffner, Steve Campbell, Amir Kalev, Kanu Sinha|
|Period||September 2022 - August 2025|
|Scheme||John Templeton Foundation Large Grants|
The Maryland Quantum-Thermodynamics Hub aims to serve as a lodestone for quantum-thermodynamics research in North America, as part of an international network.
Theory and Simulation of Magnetic Tunnel Junctions for Neuromorphic Computing
|Grant Holders||Emmanuel Bogacz and Andrew Mitchell|
|Period||September 2022 - August 2026|
|Scheme||IRC Enterprise Partnership Postgraduate Scholarship, co-funded by Intel; and the Thomas Preston Scholarship|
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.
ÉQUITY: Éire Strategy for Quantum Information and Technology
|Grant Holder||Steve Campbell|
|Period||December 2021 - November 2022|
|Scheme||IRC New Foundations|
EQUITY aims to provide a snapshot of the activity in quantum information on the island of Ireland helping to identify the most promising avenues that the community can have a lasting impact in.
Dynamics and control in quantum nanoelectronics devices
|Grant Holders||George Mihailescu, Steve Campbell, and Andrew Mitchell|
|Period||September 2021 - August 2025|
|Scheme||Equal1 Labs industry-funded Postgraduate Scholarship|
ThermoComp: Thermodynamics of Quantum Computational Models
|Grant Holders||Eoin Carolan and Steve Campbell|
|Period||November 2020 - October 2024|
|Scheme||IRC Postgraduate Scholarship|
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.
SpeedDemon: Quantum Speed Limits in Thermodynamic Processes and Coherent Control
|Grant Holder||Steve Campbell|
|Period;||February 2019 - March 2024|
|Scheme||SFI Starting Investigator Research Grant|
SpeedDemon presents an ambitious research proposal aimed at designing practical schemes to achieve the ultimate control of complex quantum systems. By bringing together several fundamental bounds related to the communication of quantum information, the thermodynamic cost of computation, and the limits on the speed of a quantum evolution, SpeedDemon will develop a new paradigm for the coherent manipulation of quantum systems.
Interactions and Topology in Quantum Matter
|Grant Holders||Patrick Wong and Andrew Mitchell|
|Period||January 2018 - May 2022|
|Scheme||UCD School of Physics Postgraduate Scholarship|
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.
Theory and simulation of semiconductor quantum devices based on the charge-Kondo paradigm
|Grant Holders||Emma Minarelli and Andrew Mitchell|
|Period||January 2018 -- May 2022|
|Scheme||IRC Enterprise Partnership Postgraduate Scholarship, co-funded by Intel|
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.
Quantum-boosted functionality in single-molecule transistors
|Grant Holder||Andrew Mitchell|
|Period||September 2018 - April 2023|
|Scheme||IRC Starting Laureate Award|
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.