Abstract
Pauli spin blockade (PSB) has long been an important tool for spin read-out in double quantum dot (DQD) systems with interdot tunneling t. In this paper we show that the blockade is lifted if the two dots experience distinct effective magnetic fields caused by site-dependent g-tensors g L and g R for the left and right dot, and that this effect can be more pronounced than the leakage current due to the spin–orbit interaction (SOI) via spin-flip tunneling and the hyperfine interaction (HFI) of the electron spin with the host nuclear spins. Using analytical results obtained in special parameter regimes, we show that information about both the out-of-plane and in-plane g-factors of the dots can be inferred from characteristic features of the magneto-transport curve. For a symmetric DQD, we predict a pronounced maximum in the leakage current at the characteristic out-of-plane magnetic field which we term the g-tensor resonance of the system. Moreover, we extend the results to contain the effects of strong SOI and argue that in this more general case the leakage current carries information about the g-tensor components and SOI of the system.
Highlights
The basic unit in quantum information processing is the qubit, the quantum version of a classical bit
In this paper we show that the blockade is lifted if the two dots experience distinct effective magnetic fields caused by site-dependent g-tensors gL and gR for the left and right dot, and that this effect can be more pronounced than the leakage current due to the spin–orbit interaction (SOI) via spin-flip tunneling and the hyperfine interaction (HFI) of the electron spin with the host nuclear spins
The orientation can be obtained from other transport investigations as described in reference [12], while the g-tensors can be extracted from the Kondo splitting in magneto-conductance investigations [63], Zeeman energy measurements [64, 65] or electron dipole spin resonance lines [9, 20]. (ii) Using the angular dependence of the maximum position, one may obtain the orientation of the spin–orbit vector if its magnitude and the g-tensors in the dots are known (figures 4(c) and (d)). (iii) if the orientation and magnitude of the spin–orbit vector are known, we can gain information about the g-tensors in the dots, extending the range of validity of the methods discussed in section 3 to include systems with strong SOI such as hole double quantum dot (DQD) in Ge
Summary
Department of Physics, University of Konstanz, D-78457 Konstanz, Germany ∗ Author to whom any correspondence should be addressed. Keywords: Pauli spin blockade, spin qubits, g-tensor, spin orbit interaction, quantum dots, double quantum dot Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.