Related Experiment Video
Updated: Feb 27, 2026
09:19
Fabrication and Characterization of Disordered Polymer Optical Fibers for Transverse Anderson Localization of Light
Published on: July 29, 2013
12.0K
Entanglement and Nonlocality in Infinite 1D Systems
Zizhu Wang1, Sukhwinder Singh1, Miguel Navascués1
1Institute for Quantum Optics and Quantum Information (IQOQI) Vienna, Austrian Academy of Sciences, Boltzmanngasse 3, 1090 Vienna, Austria.
Physical Review Letters
|June 24, 2017
Summary
Detecting quantum entanglement and nonlocality in one-dimensional translation-invariant systems is challenging. New methods using nearest-neighbor information can identify these quantum properties in infinite systems and large condensed matter systems.
Area of Science:
- Quantum information science
- Condensed matter physics
- Quantum foundations
Background:
- Detecting entanglement and nonlocality in quantum systems is crucial for quantum information processing.
- One-dimensional translation-invariant (TI) systems present unique challenges due to their infinite nature and limited local information.
- Distinguishing classical correlations from quantum entanglement is a fundamental problem.
Purpose of the Study:
- To develop methods for detecting entanglement and nonlocality in 1D infinite TI quantum systems using only near-neighbor information.
- To characterize the set of local separable states and classical correlations in TI systems.
- To devise Bell inequalities and demonstrate their violation in TI quantum states.
Main Methods:
- Characterization of local states in multiseparable TI spin chains.
- Construction of linear witnesses based on nearest-neighbor reduced density matrices.
- Proof that classical TI boxes form a polytope.
- Generation of Bell inequalities for classical TI boxes.
- Application of matrix product state algorithms to violate Bell inequalities.
Main Results:
- Demonstration that local separable states can have nonclassical TI extensions.
- Development of a simple characterization for local states in TI spin chains.
- Construction of linear witnesses to detect entanglement from nearest-neighbor information.
- Identification of classical TI boxes as a polytope.
- Generation of Bell inequalities to characterize classical TI boxes.
- Experimental demonstration of Bell inequality violation in TI quantum states using matrix product states.
Conclusions:
- Entanglement and nonlocality can be detected in 1D infinite TI systems using only local, nearest-neighbor information.
- The developed methods provide a powerful tool for characterizing quantum correlations in complex systems.
- These findings have implications for quantum information processing and understanding the foundations of quantum mechanics.
- The techniques are adaptable for detecting entanglement and nonlocality in large, finite 1D condensed matter systems.
Related Concept Videos
01:10First Law: Particles in One-dimensional Equilibrium
8.3K
Newton's first law of motion states that a body at rest remains at rest, or if in motion, remains in motion at constant velocity, unless acted on by a net external force. It also states that there must be a cause for any change in velocity (a change in either magnitude or direction) to occur. This cause is a net external force. For example, consider what happens to an object sliding along a rough horizontal surface. The object quickly grinds to a halt, due to the net force of friction. If...
8.3K
01:18First Law: Particles in Two-dimensional Equilibrium
16.9K
Recall that a particle in equilibrium is one for which the external forces are balanced. Static equilibrium involves objects at rest, and dynamic equilibrium involves objects in motion without acceleration; but it is important to remember that these conditions are relative. For instance, an object may be at rest when viewed from one frame of reference, but that same object would appear to be in motion when viewed by someone moving at a constant velocity.
Newton's first law tells us about...
Newton's first law tells us about...
16.9K
01:23Linear time-invariant Systems
998
A system is linear if it displays the characteristics of homogeneity and additivity, together termed the superposition property. This principle is fundamental in all linear systems. Linear time-invariant (LTI) systems include systems with linear elements and constant parameters.
The input-output behavior of an LTI system can be fully defined by its response to an impulsive excitation at its input. Once this impulse response is known, the system's reaction to any other input can be...
The input-output behavior of an LTI system can be fully defined by its response to an impulsive excitation at its input. Once this impulse response is known, the system's reaction to any other input can be...
998
01:26Entropy and the Second Law of Thermodynamics
16
Consider an isolated system in which a hot object is placed in contact with a cold one. This is an irreversible process that eventually leads both objects to reach the same equilibrium temperature. It is crucial to note that the constituents of any substance exhibit increased disorder at higher temperatures. As a cold substance absorbs heat, its constituents become more disordered. The energy transfer from a hotter object to a cooler one increases the system's disorder or randomness. This...
16
01:20Entropy and the Second Law of Thermodynamics
5.1K
The second law of thermodynamics can be stated quantitatively using the concept of entropy. Entropy is the measure of disorder of the system.
The relation between entropy and disorder can be illustrated with the example of the phase change of ice to water. In ice, the molecules are located at specific sites giving a solid state, whereas, in a liquid form, these molecules are much freer to move. The molecular arrangement has therefore become more randomized. Although the change in average...
The relation between entropy and disorder can be illustrated with the example of the phase change of ice to water. In ice, the molecules are located at specific sites giving a solid state, whereas, in a liquid form, these molecules are much freer to move. The molecular arrangement has therefore become more randomized. Although the change in average...
5.1K
02:39Entropy
36.8K
Salt particles that have dissolved in water never spontaneously come back together in solution to reform solid particles. Moreover, a gas that has expanded in a vacuum remains dispersed and never spontaneously reassembles. The unidirectional nature of these phenomena is the result of a thermodynamic state function called entropy (S). Entropy is the measure of the extent to which the energy is dispersed throughout a system, or in other words, it is proportional to the degree of disorder of a...
36.8K