Electro-optic quantum coherent interfaces map the amplitude and phase of a quantum signal directly to the phase or intensity of a probe beam. At terahertz frequencies, a fundamental challenge is not only to sense such weak signals (due to a weak coupling with a probe in the near-infrared) but also to resolve them in the time domain. Cavity confinement of both light fields can increase the interaction and achieve strong coupling. Using this approach, current realizations are limited to low microwave frequencies. Alternatively, in bulk crystals, electro-optic sampling was shown to reach quantum-level sensitivity of terahertz waves. Yet, the coupling strength was extremely weak. Here, we propose an on-chip architecture that concomitantly provides subcycle temporal resolution and an extreme sensitivity to sense terahertz intracavity fields below 20 V/m. We use guided femtosecond pulses in the near-infrared and a confinement of the terahertz wave to a volume of
Plasmonic materials, and their ability to enable strong concentration of optical fields, have offered a tantalizing foundation for the demonstration of sub-diffraction-limit photonic devices. However, practical and scalable plasmonic optoelectronics for real world applications remain elusive. In this work, we present an infrared photodetector leveraging a device architecture consisting of a “designer” epitaxial plasmonic metal integrated with a quantum-engineered detector structure, all in a mature III-V semiconductor material system. Incident light is coupled into surface plasmon-polariton modes at the detector/designer metal interface, and the strong confinement of these modes allows for a sub-diffractive (
- NSF-PAR ID:
- 10373319
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optica
- Volume:
- 8
- Issue:
- 12
- ISSN:
- 2334-2536
- Page Range / eLocation ID:
- Article No. 1545
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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