Todd Pittman, University of Maryland, Baltimore County
Motivated by their necessity for most fault-tolerant quantum computation schemes, we formulate a resource theory for magic states. We first show that robustness of magic is a well-behaved magic monotone that operationally quantifies the classical simulation overhead for a Gottesman-Knill type scheme using ancillary magic states. Our framework subsequently finds immediate application in the task of synthesizing non-Clifford gates using magic states.
As we approach the development of a quantum computer with tens of
well-controlled qubits, it is natural to ask what can be done with
such a device. Specifically, we would like to construct an example of
a practical problem that is beyond the reach of classical computers,
but that requires the fewest possible resources to solve on a quantum
computer. We address this problem by considering quantum simulation of
spin systems, a task that could be applied to understand phenomena in
The quantum anomalous Hall (QAH) effect is a quantum Hall effect induced by spontaneous magnetization instead of an external magnetic field. The effect occurs in two-dimensional (2D) insulators with topologically nontrivial electronic band structure which is characterized by a non-zero Chern number. The experimental observation of the QAH effect in thin films of magnetically doped (Bi,Sb)2Te3 topological insulators (TIs) paves the way for practical applications of dissipationless quantum Hall edge states.
Suspended carbon nanotube (CNT) resonators have demonstrated excellent sensitivity in mass and force sensing applications to date. I will introduce these mechanical resonators, and how they can be combined with magnetic field gradients to realize magnetic moment readout.
Realization of a quantum network that enables ecient long-distance entanglement distribution would allow for multiple impressive applications with quantum key distribution being the most prominent one.
The strong interaction of quarks and gluons is described theoretically within the framework of Quantum Chromodynamics (QCD). The most promising way to evaluate QCD for all energy ranges is to formulate the theory on a 4 dimensional Euclidean space-time grid, which allows for numerical simulations on state of the art supercomputers. We will review the status of lattice QCD calculations providing examples such as the hadron spectrum and the inner structure of nucleons.
The study of charged particles dynamics in a Paul trap is the foundation of its wide-ranging applications, including analyzing proteins, determining isotope ratios, and constructing a quantum computer. However, in the simplest case of two-particle dynamics, there remains a controversy on whether a two-ion planar crystal undergoes an order-to-chaos transition at a critical, well-defined trap parameter value. Via analytical and numerical investigation of the Mathieu-Coulomb equations, I show that the transition does not exist.
We start with an overview of chiral quantum optics as quantum light-atom interfaces with broken left- right symmetry and associated quantum optical phenomena and applications. While chiral quantum optics is traditionally discussed in context of nano-photonics and nano fibers , we propose here a novel ‘free-space’ chiral quantum optics realized as atoms in free space coupled to a ‘few-atom’ quantum antenna. In particular, we discuss free space photonic quantum links between atoms (qubits) equipped with sending and receiving quantum antennas.
Sensors based on quantum effects can measure various external quantities, such as magnetic fields, with high precision. Moreover, their sensitivity can scale more favourably with their size than is allowed classically — a property analogous to quantum speedups in computing. As with quantum computers, the performance of quantum sensors is limited by decoherence. Quantum error correction (QEC) has recently emerged as a promising approach to mitigate this decoherence, and therefore, to enhance sensitivity.