Parallel quantum state inversion of more than 10 semiconductor quantum dots is demonstrated using a single chirped laser pulse and adiabatic rapid passage.

We report the performance of deterministic III-V-based, and heralded silicon-on-insulator-based single-photon sources, and superconducting nanowire single photon detectors packaged with optical fiber ribbons operating at cryogenic temperatures. The fiber ribbons are packaged using either 3D printed polymer waveguides to connect the fibers to on-chip waveguides, or by directly bonding them to grating couplers.

Ultrashort light pulses play a critical role in our quest to observe and exploit ever-faster physical phenomena. In particular, few-cycle lasers with frequencies in the visible range enable the visualization and control of chemical and physical processes occurring on femto to attosecond timescales. In this talk, I will discuss how the interaction of these intense and ultrafast light fields with matter can be used to guide electrons in matter and generate bursts of currents on ultrafast femtosecond timescales, an emerging direction of research called lightwave electronics. Specifically, I will discuss how in the context of nanojunctions it is possible to disentangle the ultrafast laser-induced currents into contributions by real and virtual carriers and use this augmented to control landscape to design petahertz electronic logical circuits elements that operate one million times faster than present-day capabilities.

We demonstrate that high-harmonic generation from a ZnO crystal can be perturbed with non-classical light states, namely Bright Squeezed Vacuum (BSV). The perturbation with a femtosecond BSV field induces the emission of sidebands of the high harmonics that inherit the super-Poissonian statistics of BSV, and that feature a second-order single-mode correlation function g(2) > 1 that depends on the sideband order, suggesting that electron-hole pair trajectories responsible for the emission of different sidebands experience the quantum-optical interaction differently. Our results pave the way to generate coherently-controlled quantum optical states at short wavelengths and short pulse durations, both of which can boost the sensitivity of quantum sensors beyond state-of-the-art.

Quantum walks (QWs) are a valuable tool for fundamental inquiries in quantum technology, including quantum simulations, quantum search algorithms, quantum transport, and universal quantum computations. Ultrafast time-bin encoding is a promising new platform for performing photonic QWs, as it supports the scalability of QWs while retaining a significant degree of programmability and preserving excellent interferometric phase stability over extremely long periods of time. We implement an ultrafast time-bin encoding scheme for a QW with a two-photon input state––a crucial step towards building a quantum simulator capable of handling problems which cannot be solved with classical computers.

In this work, we explore the ability to change and switch between different spatial modes in a standard few-mode fiber through the use of cross-phase modulation. We characterize the switching ability for different fiber lengths and different pump powers via polarization and spatial mode tomography.