Efficient on-chip terahertz generation and detection with GaN photoconductive emitters

Can B. Uzundal; Qixin Feng; Weichen Tang; Chen Hu; Collin Sanborn; Yoseob Yoon; Sudi Chen; Jiawei Ruan; Steven G. Louie; Feng Wang

doi:10.1038/s41377-025-01870-6

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Efficient on-chip terahertz generation and detection with GaN photoconductive emitters

Original Articles

- Efficient on-chip terahertz generation and detection with GaN photoconductive emitters
- Light: Science & Applications Vol. 14, Issue 8, Pages: 2327-2334(2025)
- Affiliations：
  
  1.Department of Physics, University of California, Berkeley, CA, USA
  2.Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
  3.Department of Chemistry, University of California, Berkeley, CA, USA
  4.Graduate Group in Applied Science and Technology, University of California, Berkeley, CA, USA
  5.Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA, USA
  6.Kavli Energy NanoScience Institute, Berkeley, CA, USA
- Author bio：
  
  Feng Wang (fengwang76@berkeley.edu)
- Funds：
- DOI：10.1038/s41377-025-01870-6
  CLC：
- Received：19 November 2024，
  
  Revised：16 April 2025，
  
  Accepted：17 April 2025，
  
  Published Online：25 June 2025，
  
  Published：31 August 2025
- Accepted：
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Uzundal, C.B. et al. Efficient on-chip terahertz generation and detection with GaN photoconductive emitters. Light: Science & Applications, 14, 2327-2334 (2025).
DOI：

Uzundal, C.B. et al. Efficient on-chip terahertz generation and detection with GaN photoconductive emitters. Light: Science & Applications, 14, 2327-2334 (2025). DOI： 10.1038/s41377-025-01870-6.

摘要

Abstract

Photoconductive emitters for terahertz generation hold promise for highly efficient down-conversion of optical photons because it is not constrained by the Manley-Rowe relation. Existing terahertz photoconductive devices

however

faces limits in efficiency due to the semiconductor properties of commonly used GaAs materials. Here

we demonstrate that large bandgap semiconductor GaN

characterized by its high breakdown electric field

facilitates the highly efficient generation of terahertz waves in a coplanar stripline waveguide. Towards this goal

we investigated the excitonic contribution to the electro-optic response of GaN under static electric field both through experiments and first-principles calculations

revealing a robust excitonic Stark shift. Using this electro-optic effect

we developed a novel ultraviolet pump-probe spectroscopy for in-situ characterization of the terahertz electric field strength generated by the GaN photoconductive emitter. Our findings show that terahertz power scales quadratically with optical excitation power and applied electric field over a broad parameter range. We achieved an optical-to-terahertz conversion efficiency approaching 100% within the 0.03–1 THz bandwidth at the highest bias field (116 kV/cm) in our experiment. Further optimization of GaN-based terahertz generation devices could achieve even greater optical-to-terahertz conversion efficiencies.

关键词

Keywords

references

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