Ratchet Rectification of Electromagnetic Radiation via Breaking Time Reversal Symmetry in One and Two dimensional Structures
Abstract
We propose to explore a new mechanism of generating unidirectional displacement of charges, or ratchet rectification. The ratchet transport is driven by the oscillating E field of the incident wave in one dimensional or two dimensional structures with spatiotemporal modulation. Such charge generation will find applications in the generation of frequency standards for an accurate determination of the speed of EM waves, ultrahigh resolution spectroscopy, mixing, and ultrafast and polarization sensitive detection of very short EM pulses with applications in THz imaging, sensing, and communications. For modern nanoscale semiconductor structures, the parasitic resistances and inter device connects prevent determing the ultimate response speed using conventional techniques. We will develop new characterization techniques using the ratchet structures, in which the absence of interconnects and the placement of contacts only at the edges of the array would allow the minimization of parasitics. We will show that circular or elliptically polarized EM radiation can induce not only longitudinal but also transverse electron current, breaking the inversion symmetry. Study of this new current in ratchet structures would help determine fundamental anisotropic transport characteristics.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 14, 2022
- Source ID
- FA95501910355
Entities
People
- Jimmy Xu
Organizations
- Air Force Office of Scientific Research
- Brown University
- United States Air Force