Precession of entangled spin and pseudospin in double quantum dots
- URL: http://arxiv.org/abs/2202.04186v1
- Date: Tue, 8 Feb 2022 23:00:00 GMT
- Title: Precession of entangled spin and pseudospin in double quantum dots
- Authors: Christoph Rohrmeier and Andrea Donarini
- Abstract summary: Quantum dot spin valves are characterized by exchange fields which induce spin precession and generate current spin resonances.
We generalize this setup to allow for arbitrary spin and orbital polarization of the leads.
We observe for both vectors a delicate interplay of decoherence, pumping and precession which can only be understood by considering the dynamics of the spin-pseudospin correlators.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Quantum dot spin valves are characterized by exchange fields which induce
spin precession and generate current spin resonances even in absence of spin
splitting. Analogous effects have been studied in double quantum dots, in which
the orbital degree of freedom, the pseudospin, replaces the spin in the valve
configuration. We generalize, now, this setup to allow for arbitrary spin and
orbital polarization of the leads, thus obtaining an even richer variety of
current resonances, stemming from the precession dynamics of entangled spin and
pseudospin. We observe for both vectors a delicate interplay of decoherence,
pumping and precession which can only be understood by also considering the
dynamics of the spin-pseudospin correlators. The numerical results are obtained
in the framework of a generalized master equation within the cotunneling
approximation and are complemented by the analytics of a coherent sequential
tunneling model.
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