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Updated: Aug 6, 2026
14:58
Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
Published on: June 3, 2015
Semiconductor room-temperature maser
Andreas Gottscholl1,2, Maximilian Wagenhöfer3, Valentin Baianov3
1Experimental Physics 6 and Würzburg-Dresden Cluster of Excellence ctd.qmat, Julius-Maximilians-Universität Würzburg, Würzburg, Germany. gottscholl.andreas@gmail.com.
Nature Communications
|July 24, 2026
Summary
Researchers developed the first semiconductor maser using silicon carbide (SiC) with silicon vacancies (VSi). This breakthrough enables continuous-wave operation above room temperature, paving the way for advanced maser technologies.
Area of Science:
- Quantum electronics
- Materials science
- Solid-state physics
Background:
- Semiconductor masers are crucial for advanced electronics.
- Silicon carbide (SiC) offers unique properties for quantum applications.
- Silicon vacancies (VSi) in SiC are promising for maser development.
Purpose of the Study:
- To demonstrate the first semiconductor maser based on silicon vacancies in 4H-silicon carbide.
- To explore the potential of this maser as a preamplifier and for sensitive magnetometry.
- To investigate its performance above room temperature.
Main Methods:
- Fabrication of a maser device using 4H-silicon carbide with VSi.
- Implementation of an active feedback loop to enhance resonator quality factor.
- Optical pumping techniques for microwave photon absorption and magnetometry measurements.
Main Results:
- Achieved continuous-wave maser operation above room temperature.
- Demonstrated high-performance preamplifier capabilities with >10 dB gain at 110 K.
- Enabled sensitive magnetometry with a sensitivity of 20 pT/√Hz at room temperature.
- Showcased optically pumped microwave photon absorption, reducing resonator temperature by 40 K.
Conclusions:
- Silicon carbide masers with silicon vacancies represent a significant advancement in maser technology.
- The device shows potential for compact, high-performance preamplifiers and sensitive magnetometers.
- This work lays the foundation for electrically driven maser diodes and room-temperature maser applications.
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