Single organic molecules make excellent single photon sources, emitting photons with high efficiency and at favourable wavelengths for coupling to other quantum systems, including alkali atoms. I will discuss techniques to create organic crystals containing single photon emitting molecules, and our recent results applying strain to these crystals to tune their emission wavelength. I will show that subsequent photons emitted by a single molecule can undergo quantum interference at a beam splitter, a vital tool in optical quantum computing and communication, and will discuss how discuss how to assess photon indistinguishability using both continuous and pulsed lasers. While molecular excitation and radiative emission is efficient, generated photons can be difficult to collect without the use of photonic structures. I will discuss our recent efforts in coupling single molecules to waveguides and nanophotonic cavities.

Future quantum networks will enable unprecedented applications, ranging from secure communication to quantum-sensor networks. Qubits based on single rare-earth ions are promising candidates to act as nodes in such networks. We make use of single Yb3+ ions in YVO4, embedded in photonic crystal cavities. The vanadium (V) nuclear spins provide a dense nuclear spin bath, which can be used to store quantum states. Due to the Yb ions' orientation relative to neighboring V spins, control has been limited to next-nearest-neighbor spins. We work towards extending the resources for quantum state storage by the development of the nearest-neighbor spin control, enabled by an off-axis off-chip radiofrequency drive. Furthermore, we investigate what limits the qubit lifetime and coherence, using a crystal with a lowered concentration of Yb and paramagnetic defects. Additionally, we study the effect of an interacting spin bath using a cluster correlation expansion model. This work will enable the further exploration of sensing protocols in complex spin environments, the development of coherence preserving pulse sequences, and storage of quantum states in high-dimensional Hilbert spaces.

Integrated quantum photonic system has become a promising candidate for next-generation quantum optical system. Thanks to the scalability and strong light-matter interactions, such nanophotonic systems can realize compactness, large-scale integration, stability, and novel optical functionalities simultaneously. In this talk, I will introduce our experimental works in the fields of the integrated lithium niobate photonics. First, we demonstrate a set of nonlinear photon-pair generations for the nonlinear quantum photonic sources. Next, I will show our works on lithium-niobate integrated quantum photonic circuits for the application in quantum communications and variational quantum simulations.

We report the designs and the fabrication of optical intensity masks which enable trapping of two-dimensional arrays of cooled atoms of two atomic species, using single laser. Compared to previous realizations using active optical components, e.g., spatial light modulators, these passive optical masks reduce the complexity of neutral-atom experiments. The optical intensity masks are easily scalable to enable the trapping of large arrays of single atoms, enabling future applications in quantum sensing, networking, and computing.

In this presentation, we delve into hBN’s potential as a host for photon emitters. In our recent publication, we introduced a method for creating defects in hBN with tailored spectral properties and spatial distributions using ion beam irradiation. We demonstrate that gallium ions efficiently produce emitters, with Raman spectroscopy identifying defect vibrational signatures. Spectral tuning over 200 nm is achieved through thermal annealing, regardless of ion species, energy, or density. This process is confirmed by Raman spectroscopy, indicating changes in defects' configurations. Coupling a focused ion beam system with annealing, we achieve precise control over emitters' spectral and spatial properties, advancing quantum technologies by enabling customization of emitter properties in hBN.

Classical and quantum light sources play a fundamental role in science and technology. However, scaling the power of lasers has always come at the cost of single mode operation, a scaling question that has been investigated, without success, since the invention of lasers in 1958. I will propose a solution to this question and discuss a “scale-invariant” laser that remains single mode irrespective of its cavity size. I will conclude that mirrors are bad for the scaling of lasers and that the Berkeley Surface Emitting Laser (BerkSEL or BKSEL) solves a more than six decades open question.

In this presentation, we will discuss recent advances in the massively parallel manipulation of electromagnetic waves on chip-scale photonic systems using nonlinear photonic devices, computational optimization, and photonic-electronic systems. These advances enable applications including, but not limited to, data communications at two terabits per second. Furthermore, we will explore nonlinear photonics, including our experimental insights into second- and third-order nonlinear photonic processes, classical and non-classical parametric oscillations, and optical gain elements. This presentation will also introduce computational optimization techniques for designing photonic devices with desired functionalities.

Nanophotonic structures provide nearly arbitrary controls of light, including with nonlinear interactions to modify optical frequency. Moreover, integration of nanophotonics addresses challenging requirements in complex systems for optical metrology. Nanophotonics open up versatile tools for measuring time, transmitting data, identifying chemicals, sensing distance, searching for new physics, and supporting quantum-information science. I will describe the development of nonlinear nanophotonics devices that provide diverse controls of visible light, generate novel broadband laser sources, and enable integration of quantum sensors.

We hereby present our recent work related to the interaction of light with vapor and 2-D materials, enhanced by metasurfaces. Both free space and guided wave configurations will be discussed. We will show how Rubidium vapor and other species can modulate the phase and amplitude of the local field, benefiting from the strong enhancement of the light-matter interactions.

In this work, i will discuss the emerging field of hBN quantum photonics. I will show how to engineer scalable photonic devices from hBN, and present new spectroscopic evidence for spectral hole burning and evidence for coherent emission.

Coupling optical transitions to a single mode of an optical cavity can to enable generation of indistinguishable single photons, nonlinear-optical applications, quantum transduction, and control of chemical pathways. For all of these applications, coupling strengths need to be large compared to decoherence rates of the emitter. I will discuss progress towards this goal for various quantum emitters, including semiconductor nanocrystals (quantum dots), defects in silicon, and organic molecules. I will emphasize in particular the use of plasmonic nanocavities, which can have mode volumes well below the diffraction limit, and thus can provide coupling strengths than enable quantum photonics at room temperature.