An introduction to Quantum Technologies - with Professor Tim Spiller
okay I hope everyone can see my slides and hear me so great pleasure to talk to you this evening I was doing a little calculation and uh it's almost exactly 40 years since I was uh sitting my finals exams for for my degree in physics and it's very interesting to note that in that 40 years uh a great deal has happened in in in the subject area of quantum physics and so if if you know about the history of quantum physics then in fact it started its development uh in the early part of the last century with the work of Einstein and Planck and then uh Max born and Schrodinger and Heisenberg and Iraq and many more so so the quantum physics uh that I was taught was all developed rather rather earlier than that and the fundamental features of quantum physics that I'll I'll briefly mention in just a minute uh we're all known and understood but there have been two major developments really in last 40 years since since I finished my Physics degree and and those two things are firstly that in terms of of being able to do experiments and manipulate Quantum things uh 40 years ago people could generally do experiments with Collections and Quantum things and manipulate them them around and and over the last 40 years what they've now been able to do is isolate individual Quantum things and control them and manipulate them or a small number of them so they can now in Laboratories all over the world do fantastic experiments where they control Quantum systems so that's been one big jump forward the other big jump is that we've learned that there are uh there are new technologies that can now be built on these very fundamental features of quantum physics and that's what I'm going to be talking about so so uh if I can get my slides to move forward so so that that's the purpose of my talk to try and explain a little bit about these these new technologies so so as I say 40 odd years ago when I was learning about quantum physics the the fundamental features uh were all understood but they were regarded as things that didn't impact everyday life they were things you needed to understand to do experiments in laboratory somewhere but they weren't something that could have any impact on on people everywhere but but we now know that it's all all different and and in fact there are whole new technologies now that are underpinned by these basic fundamental features of quantum physics the things that make it different from from everyday life and classical physics and and if you like your intuition and so so I've I've named these these things with their proper words so there's there's three really three features of quantum physics that that make it it counter-intuitive and and those three things uh I'll explain in a little more in just a minute and they are the idea of superposition the idea of entanglement and the idea that you disturb things when you measure them and so we'll see how these can underpin new technologies and the really interesting thing about these new technologies is because they're built on something different they have new abilities and and they have the potential to outperform uh The Familiar information technology that that we all use today and so the first of these that I'll mention is is really Computing and so in quantum mechanics things can be in superposition and what that means is that they can be in many different states at the same time and so if I wave my hands and say suppose you had a computer chip that that worked according to the laws of quantum mechanics that computer could operate and do many many calculations all at the same time in the same device so it's like parallel processing but all those parallel processors are all in the same physical Quantum system if if you can do that if you can do many many calculations at the same time then if you can manipulate all of those calculations together you can do something which is far more efficient than you can do with an ordinary computer you can do calculations that are simply Beyond any form of computer that we have currently and the applications that that you can you can achieve you can simulate and model things far better you can do cryptanalysis you can break codes and also a little more about that in that you can you can search more efficiently through databases there are all sorts of algorithms if you like that you could on a Quantum machine what do you make these things from well there's a whole lot of candidates being considered for this they're certainly superconducting devices some of you may have heard that both Google and IBM big computer companies or are building machines based on superconductivity people are trying to track tiny ions or atoms individual atoms and use those as as the building blocks of a quantum computer they're trying to use light and they're trying to use semiconductors and and little defects in diamond and also so there's various there's various candidates for what people are trying to build these machines from but but we know if we can build them we can we can we can achieve computations that we can't do by ordinary means so that's the idea of superposition in many states the next thing I want to mention is the idea of of entanglement so entanglement is is where Quantum systems such as atoms or quanta of light called photons can be intimately correlated in a way that's much much stronger than any correlations you can imagine in the real world so so these these Quantum systems can be linked and this can be over a significant distance and they can have a correlation between them which is actually stronger than any kind of uh conventional correlation now what that means is if you have a couple of these Quantum particles that are correlated and you bounce one off some object that you wish to image or detect in some way and then you bring these two these two particles back together you can actually learn something about the object with more detail or with more Precision then you can learn if you use the same sorts of atoms or light in in a conventional state so you can you can actually use as I mentioned light atoms you can also use tiny little uh little vibrational nanomechanical devices or something if you want to detect Fields such as as gravity with with greater Precision so there are various systems that you can use in an entangled state or other interesting uh Quantum states which enable you to probe systems uh more accurately so one example of this you may well have heard of the detection of gravitational waves that was achieved at the ligo detector a couple of years back well they're now upgrading the ligo detector to actually build uh build Quantum versions of it so they're actually using squeezed light in in the ligo detector in order to improve the sensitivity of detecting gravitational waves so that's one example of of quantum sensing based on on interesting Quantum states of systems the third uh fundamental feature of quadrant physics is the fact that when you measure Quantum systems you disturb them so if if you have a Quantum system and you wish to learn about it the only way you can do that is to Instagram and measure it and and when you do that you will you will disturb it and and that disturbance is fundamental in that it's built into quantum physics it's not that the the people who do the experiments will work out in a few years time how to do the experiment better and they will get around this fundamental disturbance It's actually an intrinsic part of quantum physics it's needed in fact to make quantum physics consistent with with Einstein's theory of relativity so it's not going to go away and and it is very useful from the perspective of doing secure Communications because if if people and they're always called Alice who sends stuff to Bob if Alice sends Quantum things to Bob and someone has a cheeky look in the middle then by having that cheeky look they will inevitably disturb some of the stuff that Alice is sending to Bob which means that Alice and Bob can work out that someone is trying to Eaves so you can build a secure communication system on the basis the quantum things get Disturbed when people when people measure them and and in terms of what we use to do Quantum Communications then it's light we use quantum signals of light to to establish secure Communications and this may be carried down Optical fibers the kind of things that carry conventional high-speed Communications now or it may be through free space and I'll I'll mention a little about both of those options uh later on so just to give you a bit of perspective I mentioned that that building a a computer that works according to Quantum laws uh would enable better crypto analysis and in fact it's it's a bit more serious than that in fact if someone builds a big quantum computer which would have to be very much bigger than the one that Google for example is currently operating if someone can build a very big one then they could break most of the public key encryption that is currently used for our secure internet communications and so on so I significant problem is looming if if quantum computers really are developed in the future at that kind of site so so that's one thing that's worrying the fact that that the quantum computers will break a lot of the current cryptography that we're using another serious consideration is I just mentioned Quantum sensing and imaging will enable us to detect things you know beyond what we can currently do uh the good news is that despite both of those things which you might think of as problems then there are new ways of doing secure Communications based on Alice sending Quantum teams to Bob which are immune to both of these uh both of these uh potential attacks if you like so so although we know problems at looming we also know that Solutions are Loom which is very good and in addition to to Quantum based uh Quantum based secure Communications it's also the case that these things that will be broken by a quantum computer people are also trying to work out new forms of mathematical crypto that we hope are immune to to being broken by a quantum computer and so so despite these worries we think there is a nice way forward for secure Communications in the future so people are investing in this worldwide in fact many countries or the EU and so on have active programs and and in the UK we have a very substantial program and I'm going to tell you a little bit about that so we kind of have a bit of a tradition in the UK of dropping the ball when it comes to Turning basic science into technology uh uh so we have a long history in the UK of doing fantastic basic science but then very often that has turned into technology elsewhere in the world but over about the last 20 years success of UK governments have have realized that not only should we invest in the basic science but we should also make sure that we turn that into work at technology and so quite a number of subject areas graphene included for example have benefited from investment trying to turn the basic science into into technology and and our turn if you like in the quantum regime came in in 2013. So at the end of 2013 George Osborne who was at the time the chancellor of of a coalition government found uh 270 million pounds to start a new UK Quantum Technologies program and that program started about a year later at the end of of 2014 but but this this very large investment was was to make sure that all of the basic Quantum science that have been done could actually turn into these these potential Technologies so so in the UK very substantial investment was made in in four great big projects and I'm going to tell you a little more detail about just one of those uh in a minute but there was investment in in these four large projects to actually build the Technologies there was invest investment in training and skills and all sorts of other things so there was a very substantial investment and this was a initially a five-year program so it started late 2014 and finished towards the end of last year and it's been renewed for another five years so I'm going to give you in in a minute a quick snapshot of what we've done in one of these technology hops hubs over the last five years and then a quick forward look on what we're going to be doing in the next five years and so so these four hubs that were set up in the UK kind of covered all of the technologies that I've just uh I've just tried to outline so there was a there was a hub established uh to work on on Quantum Computing and that led by the University of Oxford but in general these hubs have about 10 different universities involved plus many many companies and I'll show you all of the all of the folk involved in our Hub in just a minute but so each of these hubs is is a big substantial spread out collaboration in in across the UK and so the one led by the University of Oxford has been focusing on building uh quantum computers of various sorts there's one LED from the University of Glasgow that focuses on using light for Quantum enhanced Imaging of various things uh there is a hub led by the University of Birmingham and they use atoms to sense uh gravity and so on to find uh buried infrastructure and things like that you can build gravitational based sensors that that can that can pick out buried things uh more accurately than you can do otherwise and then there's a hub that's built on realizing secure Communications and and that's the one that I lead and so this is what we said we were going to do in in in in the last five years and and I'll tell you what we've achieved in in just a minute so so our aim was to take basic science and to push it and and to develop new technologies that can actually achieve secure Quantum Communications in a practical way and the biggest thing that we do and I'm not going to explain in detail how it works but I will talk just a little bit about it is is quantum key distribution and so this is when Alice and Bob communicate with each other and after they've managed to communicate quantumly they can share a key between themselves and that key can be used to encrypt subsequent uh Communications and protect them against these droppers so so in our Hub in in the last five years we've got about uh a tenth of that 270 million pounds and going forward for the next five years we've got a similar sized budget and and in fact going forward into the next five years uh because UK industry is now beginning to also invest in in these various Quantum Technologies then then in total the estimated budget that includes all the industrial contributions over the whole 10-year period is going to be about one billion pounds so it's a very substantial investment so before I tell you just a little bit about what what we have done and what we will be doing I'll just say a little more about about key distribution which if you like is is the the integral building block that that we we use for for Quantum Communications and it's important to understand the distinction between sharing out of keys that can be used for encryption and then the use of the keys themselves because the way it works is that is that Alice and Bob uh can share out Quantum systems uh and measure them and establish a key and work out whether anyone else knows anything about that key and that's the quantum part so so Alice and Bob need to send Quantum signals between each other to do that and as I've said this could be through optical fiber it could be uh through free space and and both of these are uh are options and it depends on on what length scales you're communicating over as to which of those uh you do and I'll I'll come back to that in just a moment but but the important thing to note is that once the communications have been done to establish the keys you can then use these keys for whatever you like you can use them to protect information you can use them for transactions over the Internet so the use of the keys once they've been distributed is not Quantum so you don't need the quantum technology to use them you just need the quantum technology to establish the keys and the important thing about Keys which are almost certainly true for for all secure Communications is that they're a consumable you use them once and then you should delete if you use them again you'll probably violate the security and people will will be able to to subsequently decrypt your your encrypted information so so in addition to establishing Quantum Keys when you want to top them up that's when you also need the quantum technology so so that's key distribution this as I said uh I I would I promised you I'd show you uh a typical so each of the four technology hubs that works in the different technology sectors will have a slide like this it shows all the various University Partners but also it shows all of all of the companies that that work with them so of course in the communications domain British Telecom obviously handle a lot of the communications in the UK and so so they're a partner with us and and we even have a working network with them now so so there's there's BT who if you like are a service provider there's all sorts of Technology providers and so on and people who will we'll use uh use secure Communications in the future so so that is that is the the slide showing all of our partners as I say it's a big distributed collaboration with about 10 universities uh all of these industrial partners so what have we done over the last five years just to show you that this that this is is is real stuff now it's not just it's not just hypothetical now it really has moved out of the laboratory and into the real world so one of the things we we've developed and we have a prototype that maybe doesn't quite look as as sexy as this picture here but it's it's getting there uh I said you can either communicate through free space or over Optical fibers and over very short distances it's clearly convenient to communicate from a handheld device to some other device through free space and so we've developed a very short-range Quantum key distribution system that can work between a handheld device such as a phone and and some device in the wall some receiver so the Bob unit would be a receiver built in the wall and you can share Quantum Keys between your personal device and and it might be your bank it might be your employer it might be your University or whatever you could you can share Keys between yourself uh and all of these institutions and then as I said you can use these Keys subsequently for for various transactions so short range you can share Quantum Keys over free space on a longer distance you can you can share uh Keys down Optical fibers and and here is the sort of test Network that we've established in the UK there's a network that now goes around Cambridge there's a network that goes around Bristol and we're borrowing pieces of optical fiber to go between Cambridge and Bristol as well there's also a network which is shown us a dotted line here that runs from Cambridge to British telecoms uh r d Center at the dastural park and we now have a working Network there between uh between the Cambridge and and BT and so we're using that to demonstrate applications of of secure content Communications along there we've also built stuff on chip University of Bristol our partner there uh showed the world's first chip to chip uh Quantum key distribution demonstration they published that a couple of years ago so that is now working and and we're now developing what we would call Next Generation to Beyond uh qkd I've already mentioned we we work very strongly with industry we have we have many industrial partners and they've been essential to uh to to getting the work done over the last five years but also now as part of the phase two which is going to run for the next five years the government is now so iscf stands for industrial strategy challenge funding and so the government as well as funding people in universities to work on on if you like taking the basic science and turning it into working technology they're now supporting businesses and universities as part of these projects as well to really make it commercializable technology so so there are many parallel projects that are now going forward in in in phase two uh to commercialize this this new technology so so that's what we've achieved in the last five years I'm not going to talk you through through the intimate detail of all of this uh in the in the next five years but but we're basically continuing to push our work forward for example on on the the fiber-based network that is going around the UK and we're hoping to expand uh that out we're going to continue our work on the short range handheld uh qkd but the one thing I I would like to highlight that we're going to be doing over the next five years which which experiments are already underway uh uh elsewhere in the world and have shown that this is feasible even if it stands really rather difficult you can do Quantum key distribution between something on the ground and uh a satellite that is orbiting around the earth or possibly uh some kind of high altitude platform that that's that's uh that's between satellite level and and the ground and so that's one big thing that we're adding to to our agenda for the next five years we want to do an experiment to demonstrate that we can exchange Quantum Keys between a small satellite about this sort of size and and a receiver on the ground so so we're pushing forward over the next five years with with very many new activities in in Quantum Communications and I'll just mention standards as well because standards are something that always are needed for for new technology so when when when new technologies emerge in order the the different pieces of new technology can can work with each other and in order to to ensure that everything uh fits together then standards are very important so so alongside developing the technology it's very important to develop uh the relevant standards okay just to show you that this really is is is here now then okay this is not Quantum communication this this is a first small step in the in that you can as well as communicate quantly you can actually use quantum devices to Generate random numbers which are very important to underpin so so as of last month there's going to be a a new version of of the Galaxy smartphone that will actually contain a little Quantum random number generated so so soon you will actually be able to buy Quantum technology like this and carry it around in your pocket so so that's that's how real it is now so I'm going to close and just leave this slide up for a minute if people are interested in learning a bit more about this then then there's a whole website for the whole UK National program which which includes all four of those hubs and various other activities if you're interested in particular in Quantum Communications you could read about our stuff and if you're interested in reading about uh about all of the quantum Technologies in in a in a nice uh sort of low-level article that was written for for government then then then you can read the blanket review on Quantum technology so it was published just a couple of years ago so so with that I'm going to say thank you very much and uh I'm gonna stop sharing my screen now but we can put it back up if people want and and we'll take questions so thank you very much
2024-12-23 19:56
