The magneto-optics in quantum wires comprised of vertically stacked quantum dots: A call for the magnetoplasmon qubits

We embark on the collective excitations in a quantum wire made-up of vertically stacked, self-assembled InAs/GaAs
quantum dots in the presence of an applied magnetic field in the symmetric gauge. We compute and illustrate the
influence of an applied magnetic field on the behavior characteristics of the density of states, Fermi energy,
and collective (magnetoplasmon) excitations [obtained within the framework of random-phase approximation (RPA)].
The Fermi energy is observed to oscillate as a function of the Bloch vector. Remarkably, the intersubband
single-particle continuum splits into two with a collective excitation propagating within the gap. This is
attributed to the (orbital) quantum number owing to the applied magnetic field. Strikingly, the alteration in
the well- and barrier-widths can enable us to customize the excitation spectrum in the desired energy range.
These findings demonstrate, for the very first time, the viability and importance of studying the VSQD subjected
to an applied magnetic field. The technological promise that emerges is the route to devices exploiting
magnetoplasmon qubits as the potential option in designing quantum gates for the quantum communication networks.
[See, e.g., M.S. Kushwaha, Europhys. Lett. {\bf 127}, 37004 (2019).]