RQS Seminar

Abstract: The pillars of quantum theory include entanglement and operators' failure to commute. The Page curve quantifies the bipartite entanglement of a many-body system in a random pure state. This entanglement is known to decrease if one constrains extensive observables that commute with each other (Abelian ``charges''). Non-Abelian charges, which fail to commute with each other, are of current interest in quantum information and thermodynamics.

In recent years, there have been rapid breakthroughs in quantum technologies that offer new opportunities for advancing the understanding of basic quantum phenomena; realizing novel strongly correlated systems; and enhancing applications in quantum communication, computation, and sensing. Cutting edge quantum technologies simultaneously require high fidelity quantum-limited measurements and control.

Quantum computers offer the potential to perform simulations of nuclear processes that are infeasible for classical devices.

The central philosophy of statistical mechanics and random-matrix theory of complex systems is that while individual instances are essentially intractable to simulate, the statistical properties of random ensembles obey simple universal “laws”. This same philosophy promises powerful methods for studying the dynamics of quantum information in ideal and noisy quantum circuits – for which classical description of individual circuits is expected to be generically intractable.

Near-term quantum information processors will not be capable of quantum error correction, but instead will implement algorithms using the physical native interactions of the device. These interactions can be used to implement quantum gates that are often continuously-parameterized (e.g., by rotation angles), as well as to implement analog quantum simulations that seek to explore the dynamics of a particular Hamiltonian of interest.

Analog quantum simulators have the potential to provide new insight towards naturally occurring phenomena beyond the capabilities of classical computers in the near term. Incorporating controllable dissipation as a resource enables simulation of a wider range of out-of-equilibrium processes such as chemical reactions. In this talk, I will describe an experiment where we operate a hybrid qubit-oscillator circuit quantum electrodynamics processor and use it to model nonadiabatic molecular reaction dynamics through a so-called conical intersection.

Quantum devices hold promise to outperform classical computers in performing some physical simulations in the nearest future, making them a valuable tool for physics research. In this talk, Oles will focus on quantum simulation of the topological states of matter hosting Majorana modes -- the exotic "half-electron" states. He will show the results obtained from noisy quantum hardware provide us with accurate prediction of Majorana mode wavefunctions. This experiment also allows us to verify the topological nature of observed modes.

Real-time control software and hardware is essential for operating modern quantum systems. In particular, the software plays a crucial role in bridging the gap between applications and real-time operations on the quantum system. Unfortunately, real-time control software is an often underexposed area, and many well-known software engineering techniques have not propagated to this field. As a result, control software is often hardware-specific at the cost of flexibility and portability.