Non-equilibrium quantum simulators for quantum technologies
Lead Research Organisation:
University of Sussex
Department Name: Sch of Mathematical & Physical Sciences
Abstract
The goal of the project is to study theoretically the applications of quantum states of atomic quantum simulators to quantum sensing.
In recent years an intense experimental and theoretical activity has been carried out in the field of quantum simulation. Here, systems of many atoms or qubits are used to emulate the physics of complex quantum systems like quantum magnets, superfluids and high-Tc superconductors. The supervisor has contributed to this field with several proposals for quantum simulation with trapped ions , and more recently, the implementation of superradiant models in solid-state quantum optics , amongst other works.
During this project, the student will investigate the applications of quantum simulators in quantum sensing. Whereas both quantum sensing and quantum simulation are by now established research areas, the interface between those fields remains vastly unexplored. The project will open a new research avenue, in which entanglement generated in quantum simulators will be exploited to enhance precision measurements. A preliminary work in this direction has recently shown that a synthetic magnet implemented with trapped ions becomes an accurate probe of an external magnetic field when close to a phase transition . The student will have the opportunity to get trained in an increasingly active research field and work in applications with an immediate impact in quantum technology.
The methodology will rely on theoretical tools to describe quantum optical systems, such as master equations and the derivation of effective Hamiltonians. We will also use numerical algorithms to describe the quantum dynamics of many-body systems, like the Density Matrix Renormalization Group method, and other algorithms relying on Matrix Product States.
In recent years an intense experimental and theoretical activity has been carried out in the field of quantum simulation. Here, systems of many atoms or qubits are used to emulate the physics of complex quantum systems like quantum magnets, superfluids and high-Tc superconductors. The supervisor has contributed to this field with several proposals for quantum simulation with trapped ions , and more recently, the implementation of superradiant models in solid-state quantum optics , amongst other works.
During this project, the student will investigate the applications of quantum simulators in quantum sensing. Whereas both quantum sensing and quantum simulation are by now established research areas, the interface between those fields remains vastly unexplored. The project will open a new research avenue, in which entanglement generated in quantum simulators will be exploited to enhance precision measurements. A preliminary work in this direction has recently shown that a synthetic magnet implemented with trapped ions becomes an accurate probe of an external magnetic field when close to a phase transition . The student will have the opportunity to get trained in an increasingly active research field and work in applications with an immediate impact in quantum technology.
The methodology will rely on theoretical tools to describe quantum optical systems, such as master equations and the derivation of effective Hamiltonians. We will also use numerical algorithms to describe the quantum dynamics of many-body systems, like the Density Matrix Renormalization Group method, and other algorithms relying on Matrix Product States.
Organisations
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| EP/N509784/1 | 01/10/2016 | 30/09/2021 | |||
| 1815380 | Studentship | EP/N509784/1 | 01/10/2016 | 31/03/2020 | Charlie Nation |
| Description | A large and fundamental problem in the foundations of statistical mechanics is how it emerges from individual quantum systems. One intuitively expects statistical behavior when the dynamics of a system becomes complex in some meaningful way, to see this picture the opposing case: a simple system is not expected to behave statistically, but via simple, periodic motion. We have developed a framework using ideas from quantum chaos, and random matrix theory, to derive a previously hypothesized mechanism for the emergence of statistical physics from a closed quantum system under realistic assumptions. This has been published in the New Journal of Physics. Further, we have developed this framework to describe the dynamics of equilibration of closed chaotic quantum systems, and found an experimentally testable theorem that is related to classical fluctuation theorems of Brownian motion. This has both fundamental interest in the field of quantum statistical physics and thermalization, as well as to experimental syatems such as quantum simulators. This is due to an experimentally testable relation that we believe will have significant impact in the field of quantum simulation, which provides a reasonable measure of the 'complexity' of a closed quantum systems. Essentially this will potentially allow a comparison between a calculation made with a quantum simulator, to the required classical computational requirements for the same calculation. This is a large step in the demonstration of 'quantum supremacy' of quantum computers. This has led to a publication in Physical Review E, on dynamics of observables, and a fluctuation-dissipation theorem, and a further publication in Quantum, on an experimental proposal for quantum devices to characterize device complexity. We have tested our theoretical findings with numerical calculations using exact diagonalization methods on realistic quantum spin chain systems, and found a very good agreement with our theoretical models. This further backs up previous findings that chaotic quantum systems display similar behavior to random matrices. |
| Exploitation Route | Our theoretical work may be experimentally applied, to act as a measure of complexity of quantum simulator devices. Further, the theoretical framework we have developed is a useful tool to calculate the dynamics, as well as other aspects of, chaotic quantum systems. |
| Sectors | Other |
| URL | https://quantum-journal.org/papers/q-2019-12-02-207/ |