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Updated: May 13, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Enhanced Modulation of Terahertz Generation in Optically Pumped Silicon-Based CoFeB/Ir Heterostructures.
Ruijie Peng1, Zuanming Jin1,2, Yexing Jiang1
1Terahertz Technology Innovation Research Institute, Terahertz Spectrum and Imaging Technology Cooperative Innovation Center, Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China.
Nanomaterials (Basel, Switzerland)
|May 12, 2026
Summary
We developed a silicon-compatible spintronic terahertz emitter (STE) with all-optical control. This breakthrough enables tunable terahertz generation for integrated optoelectronics, overcoming previous limitations.
Area of Science:
- Spintronics
- Optoelectronics
- Terahertz (THz) technology
Background:
- Silicon-compatible spintronic terahertz emitters (STEs) are vital for on-chip ultrafast optoelectronic integration.
- Achieving all-optical controllability of STEs is a significant challenge for advanced applications.
Purpose of the Study:
- To fabricate and demonstrate a silicon-compatible spintronic terahertz emitter with all-optical modulation capabilities.
- To investigate the mechanisms behind THz emission enhancement and modulation in a novel heterostructure.
Main Methods:
- Fabrication of a Ta-buffered CoFeB/Ir heterostructure on silicon substrates.
- Utilizing continuous-wave (CW) optical pumping for THz emission.
- Investigating THz emission bandwidth, robustness, and modulation efficiency under varying optical conditions.
Main Results:
- Demonstrated enhanced and nonlinearly modulated coherent THz emission from the CoFeB/Ir heterostructure at room temperature.
- Observed ultrabroadband THz emission (0-2.5 THz) dominated by the inverse spin Hall effect.
- Identified photothermal and photodoping effects in the silicon substrate as mechanisms for all-optical modulation, with optimized modulation at specific Ir layer thicknesses (1.2 nm).
Conclusions:
- Successfully developed an all-optical controllable, silicon-based THz source.
- The findings provide critical insights for designing next-generation on-chip THz functional devices.
- The demonstrated STE offers robustness against pump variations and tunable THz generation.
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