Characterizing drift qubits
Timothy Proctor, Sandia National Laboratories
It is essential to benchmark and characterize real-world qubits in order to understand whether they are of sufficient quality for quantum information tasks, and if they are not, so that they can be debugged. Many techniques are designed for qubits that stay constant in time, but in reality almost all qubits suffer from some form of time-dependence.
Constraint Propagation Games
Zhengfeng Ji, University of Technology, Sydney
Constraint propagation games are simple extended nonlocal games that are motivated by the propagation checking of quantum computation and have found powerful applications in the study of quantum proof systems recently. In this talk, we will introduce their definitions and basic properties, demonstrate their uses in larger games as building blocks, and illustrate the method that turns them into nonlocal games.
This is the tenth and final of the Intellectual Property (IP) Management Lunch and Learn Lecture Series. We are bringing in thought leaders in the protection and management of intellectual property, including many years of experience in relevant areas of information technology.
This session will be led by Neil Henderson and Tom Hunter.
Complexity of quantum impurity models
Sergey Bravyi, IBM Research
I will discuss classical and quantum algorithms for simulation of quantum impurity models. Such models describe a bath of free fermions coupled to a small interacting subsystem called an impurity. Hamiltonians of this form were famously studied by Anderson, Kondo, Wilson and others in 1960s.
Scaling up single-atom spin qubits in silicon
Andrea Morello, Centre for Quantum Computation & Communication Technology, University of New South Wales
The modern information era is built on silicon nanoelectronic devices. The future quantum information era might be built on silicon too, if we succeed in controlling the interactions between individual spins hosted in silicon nanostructures.
Spins in silicon constitute excellent solid-state qubits, because of the weak spin-orbit coupling and the possibility to remove nuclear spins from the environment through 28Si isotopic enrichment.
Mode-selection, purification, and ultrafast manipulation of quantum light with nonlinear waveguide devices
John Donohue, University of Paderborn
The temporal structure of quantum light offers an intrinsically high-dimensional and robust platform for encoding quantum information. In particular, the time-frequency degree of freedom can be explored in the frame of pulsed temporal modes, the ultrafast analogy to spatial Hermite-Gauss or orbital angular momentum modes. These overlapping temporal modes are naturally compatible with waveguide devices and fibre infrastructure, but present unique challenges to fully explore and exploit.
This is the ninth of the Intellectual Property (IP) Management Lunch and Learn Lecture Series. We are bringing in thought leaders in the protection and management of intellectual property, including many years of experience in relevant areas of information technology.
The speaker for this session is to be determined.
Chernoff Bound for Quantum Operations is Faithful
Nengkun Yu, Tsinghua University & University of Technology, Sydney
We consider the problem of testing two quantum hypotheses of quantum operations in the setting of many uses where an arbitrary prior distribution is given. The concept of the Chernoff bound for quantum operations is investigated to track the minimal average probability of error of discriminating two quantum operations asymptotically.
Sequential measurements, disturbance and property testing
Aram Harrow, Massachusetts Institute of Technology
We describe two procedures which, given access to one copy of a quantum state and a sequence of two-outcome measurements, can distinguish between the case that at least one of the measurements accepts the state with high probability, and the case that all of the measurements have low probability of acceptance.
Simulation of III-V Nanowires for Infrared Photodetection
Khalifa M. Azizur-Rahman, McMaster University
The absorptance in vertical nanowire (nw) arrays is typically dominated by three optical phenomena: radial mode resonances, near-field evanescent wave coupling, and Fabry–Perot (F-P) mode resonances. The contribution of these optical phenomena to GaAs, InP and InAs nw absorptance was simulated using the finite element method. The study compared the absorptance between finite and semi-infinite nws with varying geometrical parameters, including the nw diameter (D), array period (P), and nw length (L).
Existence and Uniqueness in the Quantum Marginal Problem
Joel Klassen, IQC
The quantum marginal problem asks whether a family of quantum marginals are compatible with a global quantum state. It is of central importance to a wide range of topics in both quantum many body physics and quantum information. Often it can be the case that when a family of quantum marginals are compatible with a global quantum state, that global state is unique.
Join us at the Institute for Quantum Computing for a two-week introduction to the theoretical and experimental study of quantum information processing.