What is a recent development in quantum computation?
49512158#8
As the field has progressed new quantum algorithms have been developed which provide short and long term routes towards the demonstration of the superiority of quantum computers over their classical counterparts. Cluster state computation is now generally accepted as the approach that will be used to develop a fully fledged quantum computer. Whilst development of quantum computer will require the synthesis of many different aspects of integrated optics, boson sampling seeks to demonstrate the power of quantum computation via technologies readily available and is therefore a very promising near term algorithm to doing so. In fact shortly after its proposal there were several small scale experimental demonstrations of the boson sampling algorithm
Integrated quantum photonics
38407148#2
Recently, quantum contextuality has been explored as a potential tool for quantum computing. In 2013, Robert Raussendorf showed that in general, any Mermin-like, inequality-free proof for quantum contextuality (such as the Kochen-Specker theorem) can be turned into a measurement-based quantum computation. More formally, "under quite natural assumptions for multi-qubit systems, MBQCs (measurement based quantum computations) which compute a non-linear Boolean function with sufficiently high success probability are contextual." Then in 2014, Mark Howard, et. al. showed that applying contextuality to magic state distillation (MSD) provides a means for arriving at universal, fault-tolerant quantum computing. MSD is a process by which a single qubit's polarization is increased along one of several "magic" directions and its state is considered "magic" once its polarization reaches a certain level. In particular, the group proved that states are non-contextual if and only if they cannot be used as inputs for magic state distillation. This provides a selection criteria for proper input states needed in MSD, and by extension aids in the efficient creation of magic states that, when coupled with fault-tolerant operators, allows for universal quantum computing. In both cases, contextuality has a potential advantage over other quantum computational techniques since contextuality itself can be thought of as a theory of information that is built directly into quantum mechanics. Comparatively, more traditional quantum phenomena such as entanglement and interference use delicate physical states which are incredibly susceptible to noise and very difficult to manipulate experimentally.
Quantum contextuality
25220#2
A recent review by Mikhail Dyakonov in IEEE Spectrum argues that practical quantum computers are not likely to be implemented. He says: "There is a tremendous gap between the rudimentary but very hard experiments that have been carried out with a few qubits and the extremely developed quantum-computing theory, which relies on manipulating thousands to millions of qubits to calculate anything useful. That gap is not likely to be closed anytime soon."
Quantum computing
918635#10
He then also applied quantum entanglement to optical quantum computation, where in 2005, he performed the first implementation of one-way quantum computation. This is a protocol based on quantum measurement as proposed by Knill, Laflamme and Milburn. Most recently, it has been shown that one-way quantum computation can be used to implement blind quantum computing. This solves a problem in Cloud computing, namely that, whatever algorithm a client employs on a quantum server is completely unknown, i.e. blind, to the operator of the server.
Anton Zeilinger
14864881#0
A continuous-time quantum walk (CTQW) is a quantum walk on a given (simple) graph that is dictated by a time-varying unitary matrix that relies on the Hamiltonian of the quantum system and the adjacency matrix. The concept of a CTQW is believed to have been first considered for quantum computation by Edward Farhi and Sam Gutmann; since many classical algorithms are based on (classical) random walks, the concept of CTQWs were originally considered to see if there could be quantum analogues of these algorithms with e.g. better time-complexity than their classical counterparts. In recent times, problems such as deciding what graphs admit properties such as perfect state transfer with respect to their CTQWs have been of particular interest.
Continuous-time quantum walk
6947000#2
As a theoretician, Peter Zoller has written major works on the interaction of laser light and atoms. In addition to fundamental developments in quantum optics he has succeeded in bridging quantum information and solid state physics. The model of a quantum computer, suggested by him and Ignacio Cirac in 1995, is based on the interaction of lasers with cold ions confined in an electromagnetic trap. The principles of this idea have been implemented in experiments over recent years and it is considered one of the most promising concepts for the development of a scalable quantum computer. Zoller and his researcher colleagues have also managed to link quantum physics with solid state physics. One of his suggestions has been to build a quantum simulator with cold atoms and use it to research hitherto unexplained phenomena in high temperature superconductors. Zoller's ideas and concepts attract widespread interest within the scientific community and his works are highly cited.
Peter Zoller
54782330#0
Continuous-variable quantum information is the area of quantum information science that makes use of physical observables, like the strength of an electromagnetic field, whose numerical values belong to continuous intervals. One primary application is quantum computing. In a sense, continuous-variable quantum computation is "analog", while quantum computation using qubits is "digital." In more technical terms, the former makes use of Hilbert spaces that are infinite-dimensional, while the Hilbert spaces for systems comprising collections of qubits are finite-dimensional. One motivation for studying continuous-variable quantum computation is to understand what resources are necessary to make quantum computers more powerful than classical ones.
Continuous-variable quantum information
43447720#2
Hans Briegel has developed fundamental concepts in the field of quantum information, quantum computing and quantum communication. In 2001, together with Robert Raussendorf, he introduced the concept of a one-way quantum computer or measurement-based quantum computer model, which presented a new paradigm for building a quantum computer. According to Thomson Reuter’s analysis, the publication of this work is the second most-often cited publication in the field of quantum computing research in the first decade of the 21st century. Together with his work in cluster and graph states, it led to a completely new understanding of entanglement as a resource for quantum information processing. The concept of the quantum repeater, presented by Hans Briegel and his colleagues in 1998, plays an important role in quantum communication.
Hans Jürgen Briegel
29991137#41
Quantum computing in Canada is also gaining a foothold as evidenced by D-Wave Systems, a Burnaby-based quantum computing company founded in 1999 where in May 2013 it was announced that a collaboration between NASA, Google and the Universities Space Research Association (USRA) launched a Quantum Artificial Intelligence Lab using a 512 qubit D-Wave Two that would be used for research into machine learning, among other fields of study. Though the field is still in its infancy, experiments have been carried out in which quantum computational operations were executed on a very small number of qubits. Both practical and theoretical research continues, and many national governments and military funding agencies support quantum computing research to develop quantum computers for both civilian and national security purposes, such as cryptanalysis.
Technological and industrial history of 21st-century Canada
28150695#1
The mission of CQT is to conduct interdisciplinary theoretical and experimental research in quantum theory and its application to information processing. The discovery that quantum physics allows fundamentally new modes of information processing has required that classical theories of computation, information and cryptography be superseded by their quantum generalizations. These hold out the promise of faster computation and more secure communication than is possible classically. A key focus of CQT is the development of quantum technologies for the coherent control of individual photons and atoms, exploring both the theory and the practical possibilities of constructing quantum-mechanical devices for cryptography and computation.
Centre for Quantum Technologies