Electrostatically interacting Wannier qubits in curved space

TL;DR

This paper derives a tight-binding model for position-based semiconductor qubits, explores their behavior in curved space, and demonstrates how nanowire bending affects electron localization and quantum gate implementation.

Contribution

It introduces a model for Wannier qubits in curved space and analyzes dissipation and localization effects due to nanowire bending in quantum devices.

Findings

Wave-packet localization increases with nanowire bending

Curved space effects can be simulated with programmable quantum dot systems

Dissipation processes emerge during smooth bending of semiconductor nanowires

Abstract

Derivation of tight-binding model from Schroedinger formalism for various topologies of position-based semiconductor qubits is presented in this work in case of static and time-dependent electric fields. Simplistic tight-binding model allows for description of single-electron devices at large integration scale. The case of two electrostatically Wannier qubits (that are also known as position based qubits) in Schroedinger model is presented with omission spin degrees of freedom. The concept of programmable quantum matter can be implemented in the chain of coupled semiconductor quantum dots. Indeed highly integrated and developed cryogenic CMOS nanostructures can be mapped to coupled quantum dots, whose connectivity can be controlled by voltage applied across transistor gates as well as external magnetic field. Using anti-correlation principle arising from Coulomb repulsion interaction between electrons one can implement classical and quantum inverter (Classical/Quantum Swap gate) and many other logical gates. This anti-correlation will be weaken due to the fact of quantumness of physical process is bringing coexistence of correlation and anti-correlation at the same time. One of the central results presented in this work relies on the emergence of dissipation processes during smooth bending of semiconductor nanowires both in the case of classical and quantum picture. We observe strong localization of wave-packet due to nanowire bending. The obtained results can be mapped to problem of electron in curved space, so they can be expressed by programmable position-dependent metric embedded in Schroedinger equation. Indeed semiconductor quantum dot system is capable of mimicking the curved space what provides bridge between fundamental and applied science present in implementation of single-electron devices.