Related Experiment Video
Updated: Jul 4, 2026
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Intensity-based criterion for determining exceptional point in parity-time (PT) symmetric coupled array of optical
Mahla Bahar1,2, Mojtaba Golshani3, Mostafa Motamedifar4
1Department of interdisciplinary Physics and Technology, Faculty of Science, Shahid Bahonar University of Kerman, Kerman, 7616913439, Iran.
Scientific Reports
|July 2, 2026
Summary
Researchers developed a simple intensity-based method to find the PT symmetry-breaking point in waveguide arrays. This efficient technique accurately identifies critical points in PT-symmetric systems.
Area of Science:
- Quantum physics
- Photonics
- Condensed matter theory
Background:
- Parity-time (PT)-symmetric systems exhibit unique properties related to symmetry breaking.
- Waveguide arrays are crucial platforms for studying light propagation and PT symmetry.
- Identifying the PT symmetry-breaking point is essential for understanding system behavior.
Purpose of the Study:
- To investigate propagation patterns and correlations in PT-symmetric waveguide arrays.
- To develop a novel, intensity-based criterion for determining the exceptional point (PT symmetry-breaking point).
- To provide an efficient alternative to computationally intensive methods like Hamiltonian diagonalization.
Main Methods:
- Simulating light propagation in PT-symmetric waveguide arrays with various quantum states.
- Analyzing propagation patterns and site-to-site correlation functions.
- Developing and validating a new intensity-based criterion for exceptional point detection.
- Comparing the new criterion with results from Hamiltonian eigenvalue computation.
Main Results:
- Observed distinct propagation patterns before and after the PT symmetry-breaking point.
- Successfully developed a straightforward intensity-based criterion to identify the exceptional point.
- Demonstrated excellent agreement between the proposed criterion and traditional eigenvalue methods.
- Showcased the general applicability of the criterion to tight-binding systems.
Conclusions:
- The novel intensity-based criterion offers an efficient and accurate method for identifying the PT symmetry-breaking point.
- This approach simplifies the characterization of PT-symmetric systems.
- The method's general applicability makes it valuable for a broad range of physical systems described by tight-binding models.
Related Concept Videos
01:22Intensity Of Electromagnetic Waves
The energy transport per unit area per unit time, or the Poynting vector, gives the energy flux of an electromagnetic wave at any specific time. For a plane electromagnetic wave with E0 and B0 as the peak electric and magnetic fields and traveling along the x-axis, the time-varying energy flux can be given by the following equation:
01:15Insensitive Nuclei Enhanced by Polarization Transfer (INEPT)
Insensitive Nuclei Enhanced by Polarization Transfer (INEPT) is an advanced Nuclear Magnetic Resonance (NMR) technique specifically designed to detect and enhance the signals of low-abundance nuclei, such as carbon-13 and nitrogen-15, in small molecules. The fundamental principle behind INEPT is the transfer of polarization from a more abundant and highly polarizable nucleus, typically hydrogen-1, to the low-abundance nucleus of interest. This process effectively boosts the NMR signal of the...
01:20IR Spectrum Peak Intensity: Dipole Moment
The dipole moment of a bond is the product of the partial charge on either atom and the distance between them. Dipole moments influence the efficiency of IR absorption and the peak intensity. When a bond with a dipole moment is placed in an electric field, the direction of the field determines if the bond is compressed or stretched. Electromagnetic radiation consists of an electric field component that rapidly reverses direction. It follows that polar bonds are alternately stretched and...
01:05Intensity and Pressure of Sound Waves
The intensity of sound waves can be related to displacement and pressure amplitudes by using their wave expressions and the definition of intensity. The critical step to achieve this is to write the power delivered by the particles on the wave as the product of force and velocity and simplify the force per unit area as the pressure. The velocity of the medium's particles can be derived from the displacement.
Unlike the time average of a sinusoidal term, which is zero since it is positive and...
Unlike the time average of a sinusoidal term, which is zero since it is positive and...
01:27Polar Coordinates: Problem Solving
Directional radiation patterns are central to antenna analysis, as they illustrate how signal strength varies with direction. These patterns are often modeled using polar plots, where the radial distance from the origin represents signal intensity at a given angle. A commonly used idealized form is the four-lobed rose curve, which captures the concept of directional beams in a simplified mathematical form.The four-lobed rose curve, described by r = cos(2θ), features four symmetric lobes, each...
01:20¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
When proton-coupled carbon-13 spectra are simplified by a broadband proton decoupling technique, structural information about the coupled protons is lost. Distortionless enhancement by polarization transfer (DEPT) is a technique that provides information on the number of hydrogens attached to each carbon in a molecule. While the DEPT experiment utilizes complex pulse sequences, the pulse delay and flip angle are specifically manipulated. The resulting signals have different phases depending on...