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.
Related Content
Advanced microwave electronics enabling quantum technologies
Summary Superconducting quantum computers require quantum-limited measurements at microwave frequencies in order to implement error correction. Conventionally, this is accomplished using near quantum-limited Josephson Parametric Amplifiers (JPAs). The JPAs require bulky ferrite-based circulators that prevent on-chip integration of the amplifiers with the processor and take up the majority of space and cooling power in the […]
April 1, 2020
Qubits and Quantum Effects in Biology
It is unknown whether biological processes make direct use of quantum effects, as opposed to depending merely on the influence of quantum physics on chemical bonding and molecular structure.
June 1, 2017
Quantum Sensing Applications using Quantum Communication Technology
Summary The Quantum Encryption and Science Satellite provides a platform to develop and deploy quantum sensing and metrology via photonic channels. This project will build upon ‘free-space’ quantum communication technology and explore new approaches and methods to advance two primary applications: quantum-enhanced telescopes, and spectroscopic sensing for methane detection in the atmosphere. For the […]
December 8, 2018
Free-space Polarization-selective Microcavity based on Chiral Metasurfaces
Summary Developing a new type of Fabry-Pérot cavity that allows improved control of the atoms’ emission into the cavity mode will result in enhancement of the efficiency and fidelity of quantum state transfer from photons to atoms and back. This in turn can be used to improve the performance of quantum networks and repeaters, as […]
September 19, 2019