Optically-driven optical isolation and magnetism in an integrated photonic platform
Abstract
Optical isolators, which only permit the flow of light in one direction, are necessary for future Army technologies that require phase-stabilized lasers, such as high-resolution LIDAR sensing and navigation. However, isolators are challenging to integrate with on-chip photonics due to typically weak magneto-optical interactions. Current approaches for on-chip isolators utilize millimeter-scale photonics coupled to bulky magnets or external magnetic fields. These structures present compatibility challenges both in terms of size, materials, and in the introduction of unwanted magnetic fields. Therefore, it is of critical technological relevance to explore new methods of generating optical isolation that eliminate these components. However, optical isolation demands breaking time-reversal symmetry, or Lorentz reciprocity, which is technologically challenging in the absence of magnets. In this proposal, we are exploringa new operational principle for generating optical isolation and magnetism in ultra-compact, micron-scale-footprint integrated photonics that relies purely on all-optical driving with no applied magnetic fields. Our method will leverage so-called optical spin orbit coupling(OSOC), in which the microscopic optical fields of photonic resonators and waveguides can exhibit near-perfect circular polarization in which the helicity is locked to propagation direction. This physical phenomena enables generation of pseudo-magnetic optical fields that can break time-reversal symmetry in materials that are integrated with photonics. We will have two overall technological objectives in the research. Our primary objective is to utilize OSOC to realize on chip photonic devices with broken time reversal symmetry. Specificallywe will develop optical isolators that can be driven and interfaced with integrated photonics. By eliminating the need for magnets, we can dramatically reduce the footprint and improve the compatibility of these important technologies. These isolators will find applications in Army relevant technologies such as LIDAR, autonomous vehicle navigation, high-resolution surveillance, and ballistic guidance. The secondary objective of this research proposal is to determine if OSOC in integrated photonics can optically-control magnetic solid-state memories. Specifically, we will determine if OSOC can control spin magnetism in electronically-doped TMDs. This research will break new ground in our ability to control spins in solid-state materials. If successful, the same techniques can be applied directly to more commonly utilized magnetic thin films. Such control would advance optical computing and interconnects by creating a new photonic interface with traditional solid state electronic computing. Beyond improved integration possibilities, optically driven magnetism offers additional advantages over traditional magnetic systems, including to the capability to be reconfigured at ultra-fast timescales, enabling dynamic control, and memory control without energy consuming electronics.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 09, 2020
- Source ID
- W911NF2010217
Entities
People
- Alexander A. High
Organizations
- Army Contracting Command
- United States Army
- University of Chicago