High-spectral-purity frequency-agile room-temperature sources in the terahertz spectrum are foundational elements for imaging, sensing, metrology, and communications. Here we present a chip-scale optical parametric oscillator based on an integrated nonlinear microresonator that provides broadly tunable single-frequency and multi-frequency oscillators in the terahertz regime. Through optical-to-terahertz down-conversion using a plasmonic nanoantenna array, coherent terahertz radiation spanning 2.8-octaves is achieved from 330 GHz to 2.3 THz, with ≈20 GHz cavity-mode-limited frequency tuning step and ≈10 MHz intracavity-mode continuous frequency tuning range at each step. By controlling the microresonator intracavity power and pump-resonance detuning, tunable multi-frequency terahertz oscillators are also realized. Furthermore, by stabilizing the microresonator pump power and wavelength, sub-100 Hz linewidth of the terahertz radiation with 10−15residual frequency instability is demonstrated. The room-temperature generation of both single-frequency, frequency-agile terahertz radiation and multi-frequency terahertz oscillators in the chip-scale platform offers unique capabilities in metrology, sensing, imaging and communications.
Parametric sources in quantum optics usually require some form of spectro-temporal control for conditional generation of high-purity single-photon states, but their properties have not yet been optimized using integrated microchips. Using external short-pulse lasers and separate devices for pump preparation and for photon generation, as is traditional, incurs many impediments such as reduced performance, increased loss, high cost, and limited scalability. To overcome these limitations, here we demonstrate a circuit including high-bandwidth, high-extinction ratio electro-optic modulators for pump-pulse preparation fully integrated with high-quality factor (
- NSF-PAR ID:
- 10470973
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optica Quantum
- Volume:
- 1
- Issue:
- 1
- ISSN:
- 2837-6714
- Format(s):
- Medium: X Size: Article No. 19
- Size(s):
- ["Article No. 19"]
- Sponsoring Org:
- National Science Foundation
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