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Abstract A key obstacle for all quantum information science and engineering platforms is their lack of scalability. The discovery of emergent quantum phenomena and their applications in active photonic quantum technologies have been dominated by work with single atoms, self‐assembled quantum dots, or single solid‐state defects. Unfortunately, scaling these systems to many quantum nodes remains a significant challenge. Solution‐processed quantum materials are uniquely positioned to address this challenge, but the quantum properties of these materials have remained generally inferior to those of solid‐state emitters or atoms. Additionally, systematic integration of solution‐processed materials with dielectric nanophotonic structures has been rare compared to other solid‐state systems. Recent progress in synthesis processes and nanophotonic engineering, however, has demonstrated promising results, including long coherence times of emitted single photons and deterministic integration of emitters with dielectric nano‐cavities. In this review article, these recent experiments using solution‐processed quantum materials and dielectric nanophotonic structures are discussed. The progress in non‐classical light state generation, exciton‐polaritonics for quantum simulation, and spin‐physics in these materials is discussed and an outlook for this emerging research field is provided.
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Emerging rare-earth doped material platforms for quantum nanophotonics
Abstract Rare-earth dopants are arguably one of the most studied optical centers in solids, with applications spanning from laser optoelectronics, biosensing, lighting to displays. Nevertheless, harnessing rare-earth dopants’ extraordinary coherence properties for quantum information technologies is a relatively new endeavor, and has been rapidly advancing in recent years. Leveraging the state-of-the-art photonic technologies, on-chip rare-earth quantum devices functioning as quantum memories, single photon sources and transducers have emerged, often with potential performances unrivaled by other solid-state quantum technologies. These existing quantum devices, however, nearly exclusively rely on macroscopic bulk materials as substrates, which may limit future scalability and functionalities of such quantum systems. Thus, the development of new platforms beyond single crystal bulk materials has become an interesting approach. In this review article, we summarize the latest progress towards nanoscale, low-dimensional rare-earth doped materials for enabling next generation rare-earth quantum devices. Different platforms with a variety of synthesis methods are surveyed. Their key metrics measured to date are presented and compared. Special attention is placed on the connection between the topology of each platform to its target device applications. Lastly, an outlook for near term prospects of these platforms are given, with a hope to spur broader interests in rare-earth doped materials as a promising candidate for quantum information technologies.
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- Award ID(s):
- 1843044
- PAR ID:
- 10208182
- Date Published:
- Journal Name:
- Nanophotonics
- Volume:
- 8
- Issue:
- 11
- ISSN:
- 2192-8614
- Page Range / eLocation ID:
- 2003 to 2015
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1515/nanoph-2019-0185
