Extractable quantum work from a two-mode Gaussian state in a noisy channel

Abstract

We study a Szilard engine based on a Gaussian state of a system consisting of two bosonic modes placed in a noisy channel. As the initial state of the system is taken an entangled squeezed thermal state, and the quantum work is extracted by performing a measurement on one of the two modes. We use the Markovian Kossakowski-Lindblad master equation for describing the time evolution of the open system and the quantum work definition based on the second order Rényi entropy to simulate the engine. We also study the information-work efficiency of the Szilard engine as a function of the system parameters. The efficiency is defined as the ratio of the extractable work averaged over the measurement angle and the erasure work, which is proportional to the information stored in the system. We show that the extractable quantum work increases with the temperature of the reservoir and the squeezing between the modes, average numbers of thermal photons and frequencies of the modes. The work increases also with the strength of the measurement, attaining the maximal values in the case of a heterodyne detection. The extractable work is decreasing by increasing the squeezing parameter of the noisy channel and it oscillates with the phase of the squeezed thermal reservoir. The efficiency mostly has a similar behavior with the extractable quantum work evolution. However information-work efficiency decreases with temperature, while the quantity of the extractable work increases.

Thermal number influence on the quantum teleportation of a thermal Gaussian state.

“…Using quantum teleportation protocols an unknown quantum state can be teleported, in other words, reproduced at the receiver part using the receivers resource state mode and the results of measurements performed by the sender over the initials state and communicated to the receiver via classical channel. 2 During the quantum teleportation process the initial state is destroyed, which puts it into agreement with the no-cloning theorem.…”

“…However with the increase of the distance, time of teleportation also increases, which leads to decoherence in the system. 2 Quantum teleportation of a pure Gaussian state was studied in the work . It was shown that the increase of fidelity of teleportation with the squeezing between the resource state modes and of the entanglement.…”

The effect of noisy environment on secure quantum teleportation of uni-modal Gaussian states

“…In the context of quantum teleportation, the shared entangled state between the sender and receiver serves as a critical resource. Recent research has emphasized that to achieve SQT a Ądelity of teleportation higher than 2/3 is required and the resource state must ex-hibit two-way steerability, a quantum correlation phenomenon that surpasses the strength of mere entanglement [13,41,42,43,44,45,46,47,48]. These essential conditions for twomode Gaussian states are summarized in the following subsections, namely, Subsections 2.1 and 2.2.…”

Unravelling the non-classicality role in Gaussian heat engines

“…Thus, carrying out these concepts into the quantum realm is not a straightforward task. However, developments in stochastic thermodynamics 49 , 50 , open quantum systems 11 , 51 , and quantum information theory 52 , 53 have led to significant progress in these efforts.…”