In a study published in Nano Letters, researchers found that stress induced by metal electrodes directly impacts the ability to control positions of potential minima where quantum dots form and the coupling between neighboring quantum dots.
Elastic distortion within electrostatically defined quantum dots
Scientific Achievement
Combining X-ray nanodiffraction with dynamical X-ray diffraction modeling reveals buried strain in quantum devices formed at interfaces in a thin-film hetero-structure, without a need for sectioning the sample.
Significance and Impact
Elastic distortions in active areas of GaAs/AlGaAs heterostructures will impact their use in quantum electronics based on coupled quantum dots.
Research Details
- Nanoscale variations of stress in GaAs heterostructures change the potential energy landscape of the two-dimensional electron gas limiting the control of quantum devices.
- The structure was measured without perturbing the stress state by using a new combination of x-ray dynamical diffraction modeling and nanoscale scanning x-ray diffraction microscopy (nano-SXDM) at the CNM / APS Hard X-ray Nanoprobe.
DOI: https://doi.org/10.1021/acs.nanolett.7b04603
Work was performed in part at the Center for Nanoscale Materials and Advanced Photon Source.
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