EXPLOITING RELATIVITY FOR QUANTUM INFORMATION THEORY

Lead Research Organisation: University of Nottingham
Department Name: Sch of Mathematical Sciences

Abstract

My research programme is the study of how relativistic effects can be exploited to improve quantum information tasks, a key topic of immense technological importance already today and more so for the next decades. The vantage point of these investigations is that the world is fundamentally both quantum and relativistic, and that these facts are immensely useful for the design of communication devices that are absolutely safe from eavesdropping, and of quantum computers that can quickly perform difficult computational tasks which overwhelm any classically imaginable computer. Indeed, impressive technological achievements and promises have already been derived from taking seriously solely the quantum aspects of matter: quantum cryptography and communication have become a technical reality in recent years, but the practical construction of a quantum computer still requires to understand better how to efficiently store, manipulate and read information, without prohibitively large disturbances from the environment. Throwing relativity into the equation fundamentally changes the entire game, as I could show in a series of research papers, one of which was featured in a generally accessible Science article highlighting my work (Cho, Science 2005). I propose to push this exciting line of theoretical research to the point where relativistic effects in quantum information theory can be exploited technologically.Far from yielding only quantitative corrections, relativity plays a dominant role in the qualitative behaviour of many physical systems used to implement quantum information tasks in the laboratory. The prototypical example is provided by any system involving light, be it for the transmission or manipulation of quantum information. There is no such thing as a non-relativistic approximation to light quanta, so-called photons, since these always travel at the speed of light. While relativistic quantum theory, commonly known as quantum field theory, is a very well studied subject in foundational particle physics, research in quantum information theory selectively focused almost exclusively on those aspects one can study without relativity. Thus both unexpected obstacles (such as a relativistic degradation of quantum entanglement) and unimagined possibilities for quantum information theory (such as improved quantum cryptography and hypersensitive quantum measurement devices) have gone unnoticed. The relevance of these insights, which together with co-workers, I afforded over the past few years, are evidenced by the amount of work by other researchers recognizing and building on my work. Indeed, the impact of my research extends beyond pure quantum information theory, and applications to foundational questions in cosmology and black hole physics have been found.The research I propose to complete during my Fellowship aims at providing comprehensive answers to foundational, theoretical and technological aspects of relativistic quantum information theory, exploiting and building on the intriguing results obtained so far. My overall aspiration and vision is to ultimately provide concrete solutions to key problems in the field of quantum information theory.
 
Title Short film "Hierarchy Lost" 
Description Andrzej Dragan and Ivette Fuentes collaborated in the overlap of science an art to produce a short film as part of the outreach program of this grant. The film is about a scientist making an amazing discovery: he finds himself in his work. Indeed the movie aims at transmitting through images the strong emotions behind scientific discovery. It was made in collaboration with approximately 40 artists, including W. Pokromski (Schindler's List, Perfume, etc.). Ivette Fuentes contributed to this film by helping Andrzej Dragan conceive the story, develop and write the script. 
Type Of Art Film/Video/Animation 
Year Produced 2014 
Impact The film was submitted to the Foundational Questions Institute video contest "Show me the Physics" 
URL https://www.youtube.com/watch?v=rYrBDBNih9w
 
Description The main objective of my fellowship was to find suitable ways to store and process information in a quantum relativistic setting, with the ultimate goal of exploiting relativity to improve quantum information tasks. I planned to determine how quantum information tasks such as teleportation and quantum crypography are affected when considering the relativistic aspects of spacetime. I also intended to develop new relativistic quantum technologies and protocols. I very successfully achieved the objectives of my fellowship. I showed that moving cavities, traveling wave-packets and spatially localised detectors are suitable systems for the implementation of Relativistic Quantum Information. I developed mathematical techniques to describe the motion of these systems in flat and curved space-time. Using theses techniques, I demonstrated that motion and gravity have observable effects on entanglement. I also showed that motion and space-time curvature can have observable effects on quantum teleportation and quantum cryptography. These results are relevant for satellite-based quantum technologies. I showed that relativistic effects, such as particle creation, can be exploited to produce new relativistic quantum technologies (i.e. implement quantum computation and develop novel measurement devices). In particular, I designed a quantum thermometer, an accelerometer and a gravitational wave detector capable, in principle, of improving the state of the art. I also showed that relativistic effects affect quantum clocks. I developed mathematical techniques that will enable of development of quantum technologies compatible with the notion of space-time. These include gravimeters, inertial sensors and quantum clocks. This opened a new research direction in the overlap of quantum metrology and relativity. We designed a quantum scheme to measure with high precision the local gravitational field and its gradient in the Newtonian and General Relativistic (GR) regimes using the phononic field of a BEC. The designs work on the length scale of 200 µm for the gravimeter and 100 µm for the gradiometer, therefore, has high potential for miniaturization, in particular, with atom chip technologies.
Exploitation Route P. Delsing, an experienced experimentalist, is already demonstrating some of my results in his laboratory and has obtained funding from Sweden to develop the experiments. The techniques I developed to describe the motion of quantum relativistic systems and implement tools from quantum information and quantum metrology in relativistic settings have been used by several groups (in Canada, Spain, Australia, etc) to develop the field of relativistic quantum information. Very recently, other groups have further developed the techniques that we introduced to measure temperatures using single atoms. Rupert Ursin as IQOQI Vienna carried out and experiment demonstrating my predictions on the effects of gravity and motion on acceleration. The paper, which I co-authored, has been published in Nature Communications [Fink, et.al, Nature Communications 2017]. We filed two patents showing that exploiting collective excitations and entanglement enables the miniaturization of gravity sensors without loss of precision, a major limitation of conventional atom interferometers . If the proof-of-principle experiment we propose is successful, we will open a spin-off company in Nottingham ( Quetzal) , aimed at commercializing this technology. Foreseen applications range from civil engineering (key infrastructure, finding pipes, mineshafts, or voids), aerospatial and geospatial technologies and navigation (creating precise gravity maps), transport (accurate knowledge of a vehicle's position, inertial navigation, gravimeters for automated transport), humanities (in archaeology, by finding buried structures), Earth sciences and natural-resource exploration (finding groundwater, aquifers and glaciers, as well as oil and mineral reserves), and natural hazard prevention (detecting sinkholes and subsidence).
Sectors Aerospace

Defence and Marine

Digital/Communication/Information Technologies (including Software)

URL http://rqinottingham.weebly.com
 
Description The impact on the broader scientific community and general public has already been evident. In particular, my work gained plenty of media attention (New Scientist, The Conversation, Dvice, etc). Our articles were published in high impact journals such as PRL, NJP and Sci. Rep. My team and I presented our work at prestigious international conferences and at leading research centers such as Cambridge, Vienna, Queensland, among many others. We participated in a number of outreach activities including producing and participating in videos, presenting public talks, mentions in the written media, creating a webpage Twitter and several Facebook groups to disseminate our results to the general public. The scientific community will benefit from the mathematical tool and techniques that we developed in quantum metrology, quantum information theory, quantum field theory in curved space-time, thermometry, gravitational wave detection, etc. I was invited to give public lectures about my findings in this project to the New Scientist Live event in 1018 and the New Scientist Instant expert day on quantum physics in 2017. Due to my work in the overlap of quantum information and general relativity, Sir Roger Penrose and James Tagg invited me to be founding member and Director of Physics of the Roger Penrose Institute. The physics branch will open in Nottingham in 2018.
Sector Aerospace, Defence and Marine,Digital/Communication/Information Technologies (including Software)
Impact Types Cultural

Societal

 
Description Bridging the Gaps
Amount £42,030 (GBP)
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 01/2012 
End 01/2013
 
Description INSPIRE Award
Amount £49,000 (GBP)
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 07/2014 
End 03/2016
 
Description International Exchanges Award,
Amount £5,984 (GBP)
Organisation The Royal Society 
Sector Charity/Non Profit
Country United Kingdom
Start 01/2013 
End 01/2014
 
Description New Directions Research Award
Amount £300,000 (GBP)
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 03/2013 
End 09/2014
 
Description Panel Chair 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? Yes
Geographic Reach International
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact Decisions where made on grants and fellowships obtaining EPSRC funding
Year(s) Of Engagement Activity 2014
 
Description Panel Member at Annual Meeting of the German Female Physicists Saarbruecken, Germany 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact I gave my views on how it is like to be a female working in Physics in England.

I participated in a number of interesting discussions about the role of women in science.
Year(s) Of Engagement Activity 2012
 
Description Panel member 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? Yes
Geographic Reach International
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact Decisions where made on what grant and Fellowship applications would obtain EPSRC funding
Year(s) Of Engagement Activity 2010
 
Description Panel member and project reviewer 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? Yes
Geographic Reach International
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact Decisions where made on which projects would obtain European funding

Decisions where made on which projects would obtain European funding.
Year(s) Of Engagement Activity 2014