Prediction of the spin triplet two-electron quantum dots in Si: towards controlled quantum simulations of magnetic systems

Abstract

Ground state of two-electron quantum dots in single-valley materials like GaAs is always a spin singlet regardless of what the potential and interactions are. This statement cannot be generalized to the multi-valley materials like $n$-doped Si. Here we calculate numerically the spectrum of a two-electron Si quantum dot and show that the dot with the lateral size of several nm can have the spin triplet ground state which is impossible in the single-valley materials. Predicted singlet-triplet level crossing in two-electron Si quantum dots can potentially establish the platform for quantum simulation of magnetic many body systems based on quantum dots. We suggest several examples of such systems that open a way to controlled quantum simulations within the condensed matter setting.

arXiv comment7 pages, 6 figures

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Cited by in corpus (3)

• Strong electron-electron interactions in Si/SiGe quantum dots
• Two-body Wigner molecularization in asymmetric quantum dot spin qubits
• Two-electron quantum dot in a magnetic field: Analytic solution for finite potential model