Evidence for ferromagnetic instability in a repulsive Fermi gas of ultracold atoms
Free lunch served at 12:00
Multiqubit Clifford groups are unitary 3-designs
We show that the multiqubit (including qubit) Clifford group in any even prime power dimension is not only a unitary 2-design, but also a unitary 3-design. Moreover, it is a minimal unitary 3-design except for dimension 4. As an immediate consequence, any orbit of pure states of the multiqubit Clifford group forms a complex projective 3-design; in particular, the set of stabilizer states forms a 3-design. By contrast, the Clifford group in any odd prime power dimension is only a unitary 2-design.
Parallel repetition theorems for all entangled games
In complexity theory and cryptography, parallel repetition is a natural operation to reduce the error of a game or protocol without increasing the number of rounds. Raz's parallel repetition theorem is a cornerstone result in complexity theory showing that the value of two-player one round game, when repeated in parallel, decreases exponentially fast with the number of repetitions. Although the statement is intuitive, its analysis requires sophisticated techniques in information theory.
Exploring new frontiers of quantum optical science
We will discuss recent developments at a new scientific interface between quantum optics, nanoscience and quantum information science. Examples include the use of quantum optical techniques for manipulation of individual atom-like impurities at a nanoscale and for realization of hybrid systems combining atoms and atom-like systems with novel photonic devices.
Measuring entanglement spectrum in quantum many-body systems
Free lunch served at 12:00
Some thoughts about the Quantum Van Trees inequality
When a parameter of a quantum system is a random variable, the Quantum Van Trees inequality can be used to check if the combination of quantum measurement and estimator minimizes the error. In this talk we argue that, in general, the Quantum Van Trees inequality can not be saturated; when this happens it is not possible to use it to know if we are using the best measurement strategy. We propose a modification of the Quantum Van Trees inequality and discuss possible applications.
Observation of prethermalization in trapped ion quantum spin chains
Free lunch served at 12:00
Quantum algorithms and field theory: problems and connections to quantum optics
To give a reference point for the talk, I shall briefly summarize existing results regarding quantum computing for and from quantum field theory. I'll then describe some solved or open technical problems arising in this context, mentioning possible solutions of the latter. As will be apparent from this discussion, there exist various connections with topics in quantum optics and AMO physics.
Monogamy of entanglement, no-cloning, and dissipative quantum state preparation
Monogamy of entanglement limits the distribution of quantum correlations in a many-body system. The no-cloning theorem states that quantum information cannot be copied. From quantum cryptography to quantum chemistry simulations, these principles govern our approach to quantum information processing and distinguish it from classical information processing. For the most part, mathematical investigations of the monogamy of entanglement and "no-cloning" have been independent.