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Title: Ultrafast Relaxation of Charge Carriers Induced Switching in Terahertz Metamaterials

Here, we demonstrate ultrafast switching of resonant mode in terahertz metamaterials through optical excitation of radiation-damaged silicon placed in the gap of a split-ring resonator. Upon optical excitation, we observe the dynamic transition of the fundamental resonance from ON-to-OFF state on a timescale of 4 picoseconds (ps) and then fast recovery of the resonance to the ON-state within the next 20 ps. Electric field distributions in the metamaterial unit cell derived through numerical simulations clearly support our experimental observations, showing that the high electric field at the resonator gaps, responsible for inductive-capacitive (LC) resonance, completely disappears and switches OFF the resonance after being optically excited. The ultrafast switching of the metamaterial resonance is attributed to the relaxation of the photo-carriers through the defect states of radiation-damaged silicon layer. Such ultrafast material–based active control of metamaterials can lead to the ultrafast terahertz metaphotonic devices.
Authors:
 [1] ;  [1] ; ORCiD logo [2] ;  [3]
  1. Indian Institute of Technology, Guwahati (India)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mahindra Ecole Centrale, Hyderabad (India)
Publication Date:
Report Number(s):
LA-UR-18-30111
Journal ID: ISSN 1866-6892
Grant/Contract Number:
AC52-06NA25396
Type:
Accepted Manuscript
Journal Name:
Journal of Infrared, Millimeter, and Terahertz Waves
Additional Journal Information:
Journal Volume: 39; Journal Issue: 12; Journal ID: ISSN 1866-6892
Publisher:
Springer
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
USDOE Laboratory Directed Research and Development (LDRD) Program
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Metasurface; Metamaterial; Terahertz; Ultrafast switching; Split ring resonator
OSTI Identifier:
1482017

Rao, S. Jagan Mohan, Kumar, Gagan, Azad, Abul Kalam, and Chowdhury, Dibakar Roy. Ultrafast Relaxation of Charge Carriers Induced Switching in Terahertz Metamaterials. United States: N. p., Web. doi:10.1007/s10762-018-0547-6.
Rao, S. Jagan Mohan, Kumar, Gagan, Azad, Abul Kalam, & Chowdhury, Dibakar Roy. Ultrafast Relaxation of Charge Carriers Induced Switching in Terahertz Metamaterials. United States. doi:10.1007/s10762-018-0547-6.
Rao, S. Jagan Mohan, Kumar, Gagan, Azad, Abul Kalam, and Chowdhury, Dibakar Roy. 2018. "Ultrafast Relaxation of Charge Carriers Induced Switching in Terahertz Metamaterials". United States. doi:10.1007/s10762-018-0547-6.
@article{osti_1482017,
title = {Ultrafast Relaxation of Charge Carriers Induced Switching in Terahertz Metamaterials},
author = {Rao, S. Jagan Mohan and Kumar, Gagan and Azad, Abul Kalam and Chowdhury, Dibakar Roy},
abstractNote = {Here, we demonstrate ultrafast switching of resonant mode in terahertz metamaterials through optical excitation of radiation-damaged silicon placed in the gap of a split-ring resonator. Upon optical excitation, we observe the dynamic transition of the fundamental resonance from ON-to-OFF state on a timescale of 4 picoseconds (ps) and then fast recovery of the resonance to the ON-state within the next 20 ps. Electric field distributions in the metamaterial unit cell derived through numerical simulations clearly support our experimental observations, showing that the high electric field at the resonator gaps, responsible for inductive-capacitive (LC) resonance, completely disappears and switches OFF the resonance after being optically excited. The ultrafast switching of the metamaterial resonance is attributed to the relaxation of the photo-carriers through the defect states of radiation-damaged silicon layer. Such ultrafast material–based active control of metamaterials can lead to the ultrafast terahertz metaphotonic devices.},
doi = {10.1007/s10762-018-0547-6},
journal = {Journal of Infrared, Millimeter, and Terahertz Waves},
number = 12,
volume = 39,
place = {United States},
year = {2018},
month = {10}
}

Works referenced in this record:

Magnetism from conductors and enhanced nonlinear phenomena
journal, January 1999
  • Pendry, J. B.; Holden, A. J.; Robbins, D. J.
  • IEEE Transactions on Microwave Theory and Techniques, Vol. 47, Issue 11, p. 2075-2084
  • DOI: 10.1109/22.798002