The Quantum Key Distribution (QKD) Summer School, hosted by IQC, equips graduate students and young postdoctoral fellows with a strong foundation in quantum communication, particularly quantum cryptography.
In this talk, I will present a stronger version of the Doherty-Parrilo-Spedalieri (DPS) hierarchy of approximations for the set of separable states. Unlike DPS, our hierarchy converges exactly at a finite number of rounds for any fixed input dimension. This yields an algorithm for separability testing which is singly exponential in dimension and poly-logarithmic in accuracy.
In the first part of the talk I will focus on resonant tunneling and directed transport of ultracold atoms that are strongly coupled to an optical lattice inside a ring-cavity and to which an uniform bias force is applied. The bias force induces Bloch oscillations causing amplitude and phase modulation of the lattice which resonantly modifies the site-to-site tunneling. We show how different aspects of the transport such as the direction and magnitude can be simply controlled by changing the cavity detuning.
Legal documents are omnipresent and a subject to fraudulent manipulation. Important examples include mail, drug prescriptions, sin taxes, contracts, deeds and stock certificates. Cryptography is a powerful and convenient tool that can be used to protect documents against counterfeiting, alteration, duplication and other forms of manipulation. The act of creating cryptographically-secured information that is added to a document constitutes an event that is visibly evidenced on the document.
The field of cavity optomechanics deals with a family of systems, each is composed of two coupled elements. The first one is a mechanical resonator, commonly having low damping rate, and the second one is an ancilla system, which is typically externally driven. The talk will be devoted to three configurations: a mechanical opto-microwave cavity [1] , an on-fiber optomechanical cavity [2] , and a vibrating superconducting quantum interference device (SQUID) [3].
With the rapid advance of quantum technology, it may become a real
threat that an adversary can take advantage of quantum side information
at hand to break security. In this talk, we consider the problem of
multi-source randomness extraction in the presence of a quantum
adversary, who collects quantum side information from several initially
independent classical random sources. The goal is then to extract almost
National Physical Laboratory (NPL) is developing a measurement infrastructure for traceably characterising the quantum optical components of Quantum Key Distribution (QKD) systems, one of the most commercially advanced quantum technologies, and among the first to directly harness the peculiar laws of quantum physics.
Introducing the next installment of the Quantum Industry Lecture Series (QuILS). Nathan Wiebe, a former IQC postdoctoral fellow who is currently working at Microsoft, will talk to us about what it's like to work in research for a technological powerhouse.
Recently it has been shown that Repeat-Until-Success (RUS) circuits can approximate a given single-qubit unitary with an expected number of T gates of about 1/3 of what is required by optimal, deterministic, ancilla-free decompositions over the Clifford+T gate set. In this work, we introduce a more general and conceptually simpler circuit decomposition method that allows for synthesis into protocols that probabilistically implement quantum circuits over several universal gate sets including, but not restricted to, the Clifford+T gate set.
Computing the group of units in a field of algebraic numbers is one of the central tasks of computational algebraic number theory. It is believed to be hard classically, which is of interest for cryptography. In the quantum setting, efficient algorithms were previously known for fields of constant degree. We give a quantum algorithm that is polynomial in the degree of the field and the logarithm of its discriminant. This is achieved by combining three new results.