Decoherence Effects in a Three-Level System under Gaussian Process

TL;DR

This paper investigates how Gaussian process-induced noise affects the coherence and purity of a three-level quantum system, revealing conditions for optimal preservation and comparing its robustness to multi-qubit systems.

Contribution

It provides a detailed analysis of decoherence effects under various Gaussian noise regimes and identifies parameter adjustments for enhanced quantum state preservation.

Findings

Ornstein-Uhlenbeck noise significantly disrupts system symmetry.

Proper noise parameter tuning can extend coherence and purity.

Single qutrit outperforms multi-qubit systems in coherence preservation.

Abstract

When subjected to a classical fluctuating field characterized by a Gaussian process, we examine the {purity} and coherence protection in a three-level quantum system. This symmetry of the three-level system is examined when the local random field is investigated further in the noiseless and noisy regimes. In~particular, we consider fractional Gaussian, Gaussian, Ornstein--Uhlenbeck, and~power law noisy regimes. We show that the destructive nature of the Ornstein--Uhlenbeck noise toward the symmetry of the qutrit to preserve encoded {purity and coherence} remains large. Our findings suggest that properly adjusting the noisy parameters to specifically provided values can facilitate optimal extended {purity and coherence} survival. Non-vanishing terms appear in the final density matrix of the single qutrit system, indicating that it is in a strong coherence regime. Because~of all of the Gaussian noises, monotonic decay with no revivals has been observed in the single qutrit system. In~terms of coherence and information preservation, we find that the current qutrit system outperforms systems with multiple qubits or qutrits using purity and von Neumann entropy. A~comparison of noisy and noiseless situations shows that the fluctuating nature of the local random fields is ultimately lost when influenced using the classical Gaussian noises