Adiabatic many-body state preparation and information transfer in quantum dot arrays

TL;DR

This paper investigates the robustness of adiabatic ground state preparation and information transfer in quantum dot arrays, highlighting their potential for quantum simulation and the limitations posed by disorder effects.

Contribution

It demonstrates the robustness of adiabatic ground state preparation against disorder and compares it with the less effective adiabatic information transfer in quantum dot arrays.

Findings

Adiabatic ground state preparation is highly robust against exchange coupling fluctuations and hyperfine interactions.

Disorder significantly hampers adiabatic classical information transfer in spin chains.

Quantum quenches may be more effective than adiabatic evolution for information transfer in disordered arrays.

Abstract

Quantum simulation of many-body systems are one of the most interesting tasks of quantum technology. Among them is the preparation of a many-body system in its ground state when the vanishing energy gap makes the cooling mechanisms ineffective. Adiabatic theorem, as an alternative to cooling, can be exploited for driving the many-body system to its ground state. In this paper, we study two most common disorders in quantum dot arrays, namely exchange coupling fluctuations and hyperfine interaction, in adiabatically preparation of ground state in such systems. We show that the adiabatic ground state preparation is highly robust against those disorder effects making it good analog simulator. Moreover, we also study the adiabatic classical information transfer, using singlet-triplet states, across a spin chain. In contrast to ground state preparation the transfer mechanism is highly affected by disorder and in particular, the hyperfine interaction is very destructive for the performance. This suggests that for communication tasks across such arrays adiabatic evolution is not as effective and quantum quenches could be preferable.