High-power, fiber-laser-based source for magic-wavelength trapping in neutral-atom optical clocks

Theory and experiment of transient two-wave mixing in Yb-doped single-frequency fiber amplifiers induced by frequency modulation

This paper presents a theoretical and experimental characterization of an instability phenomenon observed in single-frequency fiber amplifiers when the frequency of the seed laser is modulated. The instability manifests itself as fluctuating elastic back-reflections that occur only when the frequency is decreasing with time. The theory is a generalization of a coupled-mode model developed for a single-frequency fiber amplifier back-seeded with a constant frequency shift relative to the main signal. It can explain most observed features of the experiments in a qualitative and semi-quantitative way. Open questions and directions for further developments are also discussed.

Universal Kardar-Parisi-Zhang Dynamics in Integrable Quantum Systems

Although the Bethe ansatz solution of the spin-1/2 Heisenberg model dates back nearly a century, the anomalous nature of its high-temperature transport dynamics has only recently been uncovered. Indeed, numerical and experimental observations have demonstrated that spin transport in this paradigmatic model falls into the Kardar-Parisi-Zhang (KPZ) universality class. This has inspired the significantly stronger conjecture that KPZ dynamics, in fact, occur in all integrable spin chains with non-Abelian symmetry. Here, we provide extensive numerical evidence affirming this conjecture. Moreover, we observe that KPZ transport is even more generic, arising in both supersymmetric and periodically driven models. Motivated by recent advances in the realization of SU(N)-symmetric spin models in alkaline-earth-based optical lattice experiments, we propose and analyze a protocol to directly investigate the KPZ scaling function in such systems.

Tweezer-programmable 2D quantum walks in a Hubbard-regime lattice

Quantum walks provide a framework for designing quantum algorithms that is both intuitive and universal. To leverage the computational power of these walks, it is important to be able to programmably modify the graph a walker traverses while maintaining coherence. We do this by combining the fast, programmable control provided by optical tweezers with the scalable, homogeneous environment of an optical lattice. With these tools we study continuous-time quantum walks of single atoms on a square lattice and perform proof-of-principle demonstrations of spatial search with these walks. When scaled to more particles, the capabilities demonstrated can be extended to study a variety of problems in quantum information science, including performing more effective versions of spatial search using a larger graph with increased connectivity.