JILA Science Seminar

Ultracold polar molecules possess inherent strong electric dipole moments and a rich internal structure, making them ideal platforms for implementing novel quantum information schemes, performing precision quantum metrology, and exploring exotic quantum phases such as dipolar BEC-BCS crossover in molecular Fermi gases. However, such experiments require extensive control over two or more species of atoms and their interactions, significantly scaling up the complexity and construction period of the experiment setup.

In this talk, Shinho Kim will discuss photonic systems studied across distinct spectral regimes, from the visible to the mid-infrared. His work addresses multiscale and multiphysics challenges in light–matter interactions, with each spectral regime involving fundamentally different mechanisms and applications.

Ultracold polar molecules are an exciting platform for quantum science and technology. The combination of rich internal structure of vibration and rotation, controllable long-range dipolar interactions and strong coupling to applied electric and microwave fields has inspired many applications. These include quantum simulation of strongly interacting many-body systems, the study of quantum magnetism, quantum metrology and molecular clocks, quantum computation, precision tests of fundamental physics and the exploration of ultracold chemistry.

Abstract: Efforts on quantum simulation and computation have lead to the realization of well-controlled quantum many-body systems. Due to practical constraints, they are inevitably open, i.e., coupled to the environment, which generally leads to decoherence but can also be used to stabilize interesting states. In the thermodynamic limit, the nonequilibrium steady states can undergo phase transitions due to the competition of unitary and driven-dissipative processes. After recalling general properties, we will discuss first simple examples.

Experiments with fermionic atoms in optical lattices have led to breakthroughs in understanding fundamental condensed-matter phenomena. However, elevating such experiments from a tool of scientific exploration to a computational tool capable of quantitatively predicting molecule and material properties requires overcoming decoherence with fault-tolerance techniques. Existing approaches encode qubits into atoms, losing one of the fundamental advantages of cold-atoms: their fermionic nature.

Abstract:  I will review advances to beat standard metrological limits when the quantum system is explicitly time-dependent.  In general both coherent control and adaptive strategies are required to unlock these advantages. Examples will be given in qubit systems and experiments discussed.  Recent advanced using variational methods and applications to many-body systems will also be discussed.

The scale of electronic structure calculations feasible on current or near-term quantum hardware is constrained by several inherent limitations, including coherence time, qubit count and connectivity, and device noise. All these limitations taken together severely impact the number of qubits that may be put to work constructively for chemical applications. While we have routine access to quantum computing devices exceeding 100 qubits, only a handful of these can be utilized effectively.

Abstract: Optical tweezer arrays of neutral atoms have emerged as a
promising platform for quantum science. Their geometries are highly
configurable, and excitation to Rydberg states allows the atoms to
interact. When driven by a laser, the system supports a rich phase
diagram containing both a paramagnetic and antiferromagnetic phase.
The critical point between these phases belongs to the Ising
universality class, allowing our simulator to provide direct
measurements of the universal scaling dimensions of the Ising