Atoms can be controlled by manipulating their internal states using agile, quiet and reliable laser sources. An external-cavity diode laser (ECDL) is a crucial enabling technology to realize such laser sources since it allows for the narrowing of the linewidth of a laser diode and precise tuning of the laser frequency. This project aims to miniaturize the external cavity using a photonic integrated circuit (PIC) (i.e., a single chip), which will increase the reliability and functionality of the optical frequency source for quantum experiments. A PIC ECDL will be designed and fabricated using aluminum nitride (AlN). Since several atomic transitions of interest in quantum applications are in the visible spectrum, AlN is an ideal material due to its large bandgap that allows for low-loss waveguide propagation. AlN also enables key functionality for preparing narrow linewidth and agile optical frequencies. Thus, an AlN waveguide will be fabricated and tested to ensure low waveguide losses at visible wavelengths. An external cavity feedback laser will be fabricated by coupling a laser diode directly into the AlN waveguide. A micro-ring resonator feedback circuit will be used to select and narrow the laser output. The light will be further coupled into fibre optics for delivery to atoms in a vacuum chamber, demonstrating the viability of using PIC ECDLs to interact with atomic energy levels. This AlN PIC ECDL would be a compact optical frequency source that could help enhance existing quantum experiments, enable experiments currently unviable with bulk optical setups and allow for the translation of quantum atomic technologies out of the laboratory (i.e., large-scale quantum computation, high-precision gravimeters for resource mapping and portable optical atomic clocks).
Figure 1. A conceptual render of an external cavity diode laser in an aluminum nitride integrated photonic circuit.
Spin-transfer Torque Magnetic Random Access Memory for On-chip Spin Information Storage
Summary Leakage power in semiconductor memories, such as Dynamic Random Access Memory (DRAM) and Static Random Access Memory (SRAM), can be substantial and is one of the limits for scalability of classical electronics. This is attributed to the fact that the information stored is volatile, requiring constant refreshing, as well as reprogramming upon powering […]
August 6, 2018
Scanning Tunneling Microscopy of Quantum Materials, Devices and Molecules
Summary This project advances our ability to characterize and study novel quantum materials, quantum devices, and even individual molecules at the atomic level. By combining Non-Contact Atomic Force Microscopy (NC-AFM), Scanning Tunneling Microscopy (STM) and scanning gate methods, we correlate spatial information with transport properties and can locally manipulate charge, spin and structural states. […]
January 28, 2019
Zero-Dimensional Quantum Materials for the Next Generation of Highly-Selective Chemical Sensors
Summary Heavy metals are a major public health concern and their on-site detection in water supplies is not well served by existing lab techniques. We develop a new multi-modal platform comprising functionalized quantum dots of two-dimensional materials (2D-QDs) for the sensing of four highly-toxic heavy metal pollutants (arsenic, cadmium, lead and mercury). The zero-dimensional […]
March 11, 2019
Mesoscopic systems as coherent control elements
Summary Mesoscopic systems provide a new tool for quantum systems design. In particular, they are enabling of robust quantum control. Here “mesoscopic system” refers to a connected network where each element, if studied alone, would be a quantum bit. The network is too big to be treated fully quantum mechanically. We do not have individual […]
September 1, 2016