To realize ubiquitously used photonic integrated circuits, on-chip nanoscale sources are essential components. Subwavelength nanolasers, especially those based on a metal-clad design, already possess many desirable attributes for an on-chip source such as low thresholds, room-temperature operation and ultra-small footprints accompanied by electromagnetic isolation at pitch sizes down to ∼50 nm. Another valuable characteristic for a source would be control over its emission wavelength and intensity in real-time. Most efforts on tuning/modulation thus far report static changes based on irreversible techniques not suited for high-speed operation. In this study, we demonstrate
We experimentally demonstrate bridge-coupled metallo-dielectric nanolasers that can operate in the in-phase or out-of-phase locking modes at room temperature. By varying the length of the bridge, we show that the coupling coefficients can be realized in support of the stable operation of any of these two modes. Both coupled nanolaser designs have been fabricated and characterized for experimental validation. Their lasing behavior has been confirmed by the spectral evolution, light-in light-out characterizations, and emission linewidth narrowing. The operating mode is identified from the near-field and far-field emission pattern measurements. To the best of our knowledge, this is the first demonstration of mode selection in bridge-coupled metallo-dielectric nanolasers, which can serve as building blocks in nanolaser arrays for applications in imaging, virtual reality devices, and lidars.
- Publication Date:
- NSF-PAR ID:
- 10369455
- Journal Name:
- Optics Letters
- Volume:
- 46
- Issue:
- 24
- Page Range or eLocation-ID:
- Article No. 6027
- ISSN:
- 0146-9592; OPLEDP
- Publisher:
- Optical Society of America
- Sponsoring Org:
- National Science Foundation
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