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We demonstrate a low power thermally induced optical bistability at telecom wavelengths and room temperature using a nanobeam photonic crystal cavity embedded with an ensemble of quantum dots. The nanobeam photonic crystal cavity is transfer-printed onto the edge of a carrier chip for thermal isolation of the cavity with an efficient optical coupling between the nanobeam waveguide and optical setup. Reflectivity measurements performed with a tunable laser reveal the thermo-optic nature of the nonlinearity. A bistability power threshold as low as 23 μW and an on/off response contrast of 6.02 dB are achieved from a cavity with a moderately low quality factor of 2830. Our device provides optical bistability at power levels an order of magnitude lower than previous quantum-dot-based devices.
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This content will become publicly available on July 21, 2026
Design and Characterization of Low‐Threshold InP Nanowire Photonic Crystal Surface‐Emitting Lasers
This study examines the lasing performance of optically pumped wurtzite‐phase InP nanowire (NW) photonic crystal surface‐emitting lasers (PCSELs) with the goal of optimizing the cavity design for low‐threshold lasing. By varying the photonic crystal lattice constant and NW diameter, this study systematically investigates the threshold power and the threshold gain. Using finite‐difference time‐domain simulations and gain spectra modeling, this study finds that the lowest pump threshold occurs when the cavity resonance energy is slightly above the spontaneous emission maximum energy due to high differential gain. Furthermore, PCSEL structures with an apothem‐to‐pitch ratio of ≈0.15 are advantageous because they provide increased confinement factors, resulting in the lowest lasing threshold and high laser output. This study paves the path toward low‐threshold NW PCSEL designs for photonic integrated circuits.
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- PAR ID:
- 10624916
- Publisher / Repository:
- Wiley-VCH GmbH
- Date Published:
- Journal Name:
- Advanced Photonics Research
- ISSN:
- 2699-9293
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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