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We study electron tunneling in binary quantum systems as double quantum dot (DQD) and double quantum well (DQW), considered as two-level systems. The Schrodinger equation for this system is reduced using single band kp-effective Hamiltonian, and is solved numerically. We calculate full electron spectrum E, n = 1,2 ... in the bi-confinement potential. The tunneling in DQD is studied in relation to two factors, a coupling coefficient W and an asymmetry factor A of the potential. The ratio W/A defines the electron localization in DQD. The cases of ideal and almost ideal DQD are examined and compared. We are modeling the effects of environmental influence and fluctuations of electrical pulse on the coherence of DQD based charge qubit. In particular, we show that the coupling in the ideal DQD (A=0) is unstable for any small fluctuations of A.
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Quantum sensing effect of electron tunneling in DQD/analyte complex
We investigate electron tunneling between quantum dots and molecules to propose a quantum sensor. This sensor consists of double quantum dots (DQD) with energy levels specifically tailored to mirror those of the target analyte. By analyzing the spectral distribution of electron localizations in the DQD system, we can delineate the analyte’s spectrum and deduce its composition by comparing it with a reference sample. To understand electron tunneling dynamics within the DQD/analyte complex, we performed three-dimensional computational modeling applying the effective potential approach to the InAs/GaAs heterostructure. In this modeling, we mimicked the analyte spectrum by utilizing a quantum well characterized by a quasi-discrete spectrum. Our calculations reveal the inherent potential of utilizing this method as a highly sensitive and selective sensor.
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- PAR ID:
- 10597361
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- AIP Advances
- Volume:
- 14
- Issue:
- 4
- ISSN:
- 2158-3226
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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