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Scanning tunneling electroluminescence (STL) microscopy is performed on a 3 nm‐thick InGaN/GaN quantum well (QW) with [In] = 0.23 such that the main light emission occurs in the green. The technique is used to map the radiative recombination properties at a scale of a few nanometers and correlate the local electroluminescence map with the surface topography simultaneously imaged by scanning tunneling microscopy. While the expected green emission is observed all over the sample, measurements performed on a 500 nm × 500 nm area around a 150 nm‐large and 2.5 nm‐deep hexagonal defect reveal intense emission peaks at higher energies close to the defect edges, features which are not visible in the macrophotoluminescence spectrum of the sample. Via a fitting of the local tunneling electroluminescence spectra, quantitative information on the fluctuations of the intensity, peak energy, width, and phonon replica intensity of the different spectral contributions is obtained, which provides information on carrier localization in the QW. This procedure also indicates that the carrier diffusion length on the probed area of the QW is shorter than 50 nm.
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Atomic physics on a 50-nm scale: Realization of a bilayer system of dipolar atoms
Controlling ultracold atoms with laser light has greatly advanced quantum science. The wavelength of light sets a typical length scale for most experiments to the order of 500 nanometers (nm) or greater. In this work, we implemented a super-resolution technique that localizes and arranges atoms on a sub–50-nm scale, without any fundamental limit in resolution. We demonstrate this technique by creating a bilayer of dysprosium atoms and observing dipolar interactions between two physically separated layers through interlayer sympathetic cooling and coupled collective excitations. At 50-nm distance, dipolar interactions are 1000 times stronger than at 500 nm. For two atoms in optical tweezers, this should enable purely magnetic dipolar gates with kilohertz speed.
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- PAR ID:
- 10520554
- Publisher / Repository:
- Science
- Date Published:
- Journal Name:
- Science
- Volume:
- 384
- Issue:
- 6695
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- 546 to 551
- 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/10.1126/science.adh3023
