Atomic-Photonic Hybrid Devices for Next-Generation Quantum Sensors
Lead Research Organisation:
University of Sussex
Department Name: Sch of Mathematical & Physical Sciences
Abstract
This project will develop evolutionary algorithms to find state-of-the-art quantum states for a range of applications in realistic experimental settings.
We will start with states that are known to perform a particular task well and then see how their performance is altered under 'mutations'.
The beauty of this methodology is that it is very broadly applicable. The scheme can be tailored so that it only includes operations that are currently available in the laboratory, accounts for imperfections and losses specific to a particular system, and includes the important role of implementable measurements. It can also be updated easily as new experimental capability becomes available and even be used to guide what new capability would make the most difference in the future.
We have carried out an initial toy-model of this process (see Fig. 1), which has shown that we can find new quantum states that achieve considerable gains in the precision of measurement schemes over the states that are commonly used. This is very exciting and other groups are now starting to look at evolutionary
algorithms in a different context [1]. The project will start by setting up the general algorithm. Once this is operational, we will begin by applying it to the study of nitrogen vacancy (NV) centres in diamond in the context of magnetic field sensing and secure communications [2]. We will work closely with experimental
collaborators and the constraints on the algorithm will be informed by what can be achieved in the laboratory. We will then seek broader applications in a range of systems such as cold atoms or quantum dots.
We will start with states that are known to perform a particular task well and then see how their performance is altered under 'mutations'.
The beauty of this methodology is that it is very broadly applicable. The scheme can be tailored so that it only includes operations that are currently available in the laboratory, accounts for imperfections and losses specific to a particular system, and includes the important role of implementable measurements. It can also be updated easily as new experimental capability becomes available and even be used to guide what new capability would make the most difference in the future.
We have carried out an initial toy-model of this process (see Fig. 1), which has shown that we can find new quantum states that achieve considerable gains in the precision of measurement schemes over the states that are commonly used. This is very exciting and other groups are now starting to look at evolutionary
algorithms in a different context [1]. The project will start by setting up the general algorithm. Once this is operational, we will begin by applying it to the study of nitrogen vacancy (NV) centres in diamond in the context of magnetic field sensing and secure communications [2]. We will work closely with experimental
collaborators and the constraints on the algorithm will be informed by what can be achieved in the laboratory. We will then seek broader applications in a range of systems such as cold atoms or quantum dots.
Organisations
People |
ORCID iD |
| Jacob Dunningham (Primary Supervisor) | |
| Michail Kritsotakis (Student) |
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| EP/N509784/1 | 01/10/2016 | 30/09/2021 | |||
| 1805873 | Studentship | EP/N509784/1 | 01/10/2016 | 31/05/2020 | Michail Kritsotakis |
| Description | I have been involved into three different research projects up to this point related to this grant. 1st project: We theoretically examined atomic gravimeters which are devices used to measure the gravitational acceleration with very high precision. We found the theoretical limit of the precision of these devices by using tools from estimation theory, which is better compared to what is currently considered, indicating that there is more metrological potential in these devices (more information could be gained from them). Our analysis showed that we could boost gravimeter's sensitivity by using an appropriate initial state for our atoms or by making an appropriate measurement at the end of the interferometer (which is one of the basic parts of the gravimeter). The crucial outcome of our work is that it introduces new ideas on how we can improve gravimeters' sensitivity. This project concluded to a publication (Optimal matter-wave gravimetry, Phys. Rev. A 98, 023629). 2nd project: We have examined the interaction between atoms and light in order to increase the sensitivity of a device. We create entanglement between atom and light through their interaction. That means that some atomic properties are connected (more precisely entangled) with some light properties. So if we want to measure very precisely a specific atomic observable, A, we could also make a measurement of the corresponding entangled light observable, L, in order to gain more knowledge about A. That is to say that a combined measurement of A and L would be more precise than just measuring the atomic observable A. 3rd project: Here we examine another method in order to create spin-squeezed states, which provide us with higher sensitivities in measurements, by using the atom light interaction in a cavity (and not in free space as in the second project). In this scheme we don't rely on the detector efficiency of a light observable, as we did in the second project, but instead we use the cavity feedback, in order to generate the so called one-axis twisting dynamics. This method has already been examined theoretically and experimentally. Our aim is to find any improvements to that scheme, by using the so called twist and turn dynamics, which essentially has a faster squeezing rate, and hasn't been ever examined in this concept before. We have already found some interesting results, that show improvements in the sensitivity, but we still examine other aspects of the scheme, in order order to understand better our problem. We also apply an optimization algorithm (gradient descent algorithm), in order to optimize our results over the parameters considered in our problem. |
| Exploitation Route | All three theoretical projects I have worked on can be used for further theoretical and experimental research on improving the sensitivity of interferometers. |
| Sectors | Aerospace, Defence and Marine,Environment |
| Description | Prospects for quantum-enhanced radar systems |
| Amount | £109,571 (GBP) |
| Funding ID | DSTLX1000146546 |
| Organisation | Defence Science & Technology Laboratory (DSTL) |
| Sector | Public |
| Country | United Kingdom |
| Start | 07/2020 |
| End | 06/2024 |