Quantum manipulation power for quantum information processing gets a boost

October 11, 2017

Traditionally, heat engines produce heat from the exchange between high-temperature and low-temperature baths. Now, imagine a heat engine that operates at quantum scale, and a system made up of an atom interacting with light (photons) confined in a reflective cavity of sub-atomic dimensions. This setup can either be at a high or low temperature, emulating the two baths found in conventional heat engines. Controlling the parameters influencing how such quantum heat engine models work could dramatically increase our power to manipulate the quantum states of the coupled atom-cavity, and accelerate our ability to process quantum information. In order for this to work, we have to find new ways of improving the efficiency of quantum heat engines. In a study published in EPJ D, Kai-Wei Sun and colleagues from Beihang University, Beijing, China, show methods for controlling the output power and efficiency of a quantum thermal engine based on the two-atom cavity. In the familiar heat engine model at macroscopic scale, referred to as the Carnot heat engine, the efficiency increases as a function of the ratio between the temperatures of the low-and high-temperature baths. By comparison, the efficiency of two-level quantum heat engines is related to the level of quantum entanglement in these two states, which are either at a low or a high temperature, and display the same probability of being occupied.

The authors found that their heat engine model only yields high efficiency and output power when the number of photons involved is small; accordingly, its efficiency and power output rapidly decrease as the number of photons increases. This implies the need to reduce the number of photons to improve the efficiency of these engines, so that we can increase the quantum manipulation power and realise quantum information processing based on atom-cavity systems.
Reference: K.W. Sun & R. Li, G.-F. Zhang (2017), A Quantum Heat Engine Based on the Tavis-Cummings Model, European Physical Journal D DOI: 10.1140/epjd/e2017-80101-3


Related Photons Articles from Brightsurf:

An electrical trigger fires single, identical photons
Researchers at Berkeley Lab have found a way to generate single, identical photons on demand.

Single photons from a silicon chip
Quantum technology holds great promise: Quantum computers are expected to revolutionize database searches, AI systems, and computational simulations.

Physicists "trick" photons into behaving like electrons using a "synthetic" magnetic field
Scientists have discovered an elegant way of manipulating light using a ''synthetic'' Lorentz force -- which in nature is responsible for many fascinating phenomena including the Aurora Borealis.

Scientists use photons as threads to weave novel forms of matter
New research from the University of Southampton has successful discovered a way to bind two negatively charged electron-like particles which could create opportunities to form novel materials for use in new technological developments.

The nature of nuclear forces imprinted in photons
IFJ PAN scientists together with colleagues from the University of Milano (Italy) and other countries confirmed the need to include the three-nucleon interactions in the description of electromagnetic transitions in the 20O atomic nucleus.

Pushing photons
UC Santa Barbara researchers continue to push the boundaries of LED design a little further with a new method that could pave the way toward more efficient and versatile LED display and lighting technology.

Photons and electrons one on one
The dynamics of electrons changes ever so slightly on each interaction with a photon.

An advance in molecular moviemaking shows how molecules respond to two photons of light
Some of the molecules' responses were surprising and others had been seen before with other techniques, but never in such detail or so directly, without relying on advance knowledge of what they should look like.

The imitation game: Scientists describe and emulate new quantum state of entangled photons
A research team from ITMO University, MIPT and Politecnico di Torino, has predicted a novel type of topological quantum state of two photons.

What if we could teach photons to behave like electrons?
The researchers tricked photons - which are intrinsically non-magnetic - into behaving like charged electrons.

Read More: Photons News and Photons Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.