Events

Christoph Simon, University of Calgary

Quantum optical systems are well suited for pushing the boundaries of quantum physics. Two big goals in this context are the creation of entanglement over long distances and the observation of quantum effects on macroscopic scales. I will describe various theoretical and some experimental work in these directions.

Britton Plourde, University of Syracuse 

Low-loss resonators formed from lumped circuit elements or distributed transmission lines can be coupled to superconducting qubits. This is the basis for the numerous investigations of circuit-QED over the past decade. In this case, one is primarily interested in the coupling between the qubit and one or a few modes.

 John Martinis, University of California,
Santa Barbara

As microelectronics technology nears the end of exponential growth over time, known as Moore’s law, there is a renewed interest in new computing paradigms. I will discuss recent research at UCSB on superconducting quantum bits, as well as our recent start at Google to build a useful quantum computer to solve machine learning problems.  A recent experiment will be highlighted that extends the lifetime of a qubit state using quantum error correction.

Marco Piani, University of Strathclyde, Glascow

Quantum correlations exhibit a variety of non-classical features, which include quantum entanglement, quantum steering, and quantum discord. Such richness and diversity of quantum features calls for meaningful and quantitative approaches to their study. In this talk I will illustrate how it is possible to exploit techniques and insight from convex optimization, especially from semidefinite programming, to provide an operational quantification and interpretation of all the above aspects of the quantumness of correlations.

The International QKD Summer School is a five-day program focused on theoretical and experimental aspects of quantum communication with a focus on quantum cryptography. The QKD Summer School aims to provide a solid foundation in relevant approaches and techniques to enable graduate students and young postdoctoral fellows to perform their own independent research.

Ying Dong, Hangzhou Normal University

Thermodynamics has been highly successful, impacting strongly on the natural sciences and enabling the development of technologies that have changed our lives, from fridges to jet planes. Until recently, it was applied to large systems described by the laws of classical physics. However, with modern technologies miniaturizing down to the nanoscale and into the quantum regime, testing the applicability of thermodynamics in this new realm has become an exciting technological challenge.

Ibrahim Nsanzineza, Syracuse University

Nonequilibrium quasiparticles and trapped magnetic flux vortices can significantly impact the performance of superconducting microwave resonant circuits and qubits at millikelvin temperatures. Quasiparticles result in excess loss, reducing resonator quality factors and qubit lifetimes. Vortices trapped near regions of large microwave currents also contribute excess loss. However, vortices located in current-free areascan actually trap quasiparticles and lead to a reduction in the quasiparticle loss.

Si-Hui Tan, Singapore University of Technology and Design

We introduce an approach to homomorphic encryption on quantum data.
Homomorphic encryption is a cryptographic scheme that allows
evaluations to be performed on ciphertext without giving the evaluator
access to the secret encryption key. Random operations from an finite
abelian unitary group chosen using an encryption key chosen
uniformly at random perform the encryption, and operations that lie
within the centralizer of the encryption group perform the

Nitin Jain, Northwestern University

Quantum-optical frequency conversion (QFC) provides a method, usually via a nonlinear interaction with an optical ‘pump’ beam, to keep the quantum features of an optical ‘signal’ intact. Most QFC experiments
upconvert near-infrared signal photons to those in the visible or near-visible regime due to the availability of highly-efficient detectors that can be operated at high speeds without incurring a severe noise penalty.

Chris Granade, University of Sydney

In recent years, Bayesian methods have been proposed as a solution to a wide range of issues in quantum state and process tomography. In this talk, we make these methods practical by solving three distinct problems: numerical intractability, a lack of informative prior distributions, and an inability to track time-dependent processes. Our approach allows for practical computation of point and region estimators for quantum states and channels, and allows tracking of time-dependent states.