Related Experiment Video
Updated: Jun 11, 2026
07:39
Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons
Published on: July 21, 2018
Coupled mode theory analysis of mode-splitting in coupled cavity system
1Laboratory of Photonics and Microwave Engineering, School of Information and Communication Technology, Royal Institute of Technology (KTH), Electrum 229, 164 40 Kista, Sweden.
Optics Express
|July 1, 2010
Summary
Coupling two identical cavities, either standing-wave (SW) or traveling-wave (TW), can lead to mode splitting. Coexisting direct and indirect couplings can cancel this effect, enabling tunable transmission spectra for nanophotonics.
Area of Science:
- Optics and Photonics
- Nanophotonics
- Cavity Quantum Electrodynamics
Background:
- Coupled cavity systems are fundamental in nanophotonics for controlling light.
- Understanding transmission characteristics is crucial for device design.
- Temporal coupled mode theory provides a framework for analyzing such systems.
Purpose of the Study:
- To analyze the transmission characteristics of directly and indirectly coupled identical standing-wave (SW) and traveling-wave (TW) cavities.
- To investigate the phenomenon of mode splitting in coupled cavity systems.
- To explore the possibility of controlling transmission spectra through coupled cavity configurations.
Main Methods:
- Analysis based on temporal coupled mode theory.
- Modeling of directly coupled (cavity-cavity) systems.
- Modeling of indirectly coupled (cavity-waveguide-cavity) systems.
- Examination of coexisting direct and indirect coupling effects.
Main Results:
- Mode splitting is observed in both directly and indirectly coupled systems.
- Coexisting direct and indirect couplings can offset each other, preventing mode splitting.
- Tunable transmission spectra, including Fano-type, EIT-like, and EIA-like resonances, are achievable.
- Side-coupled SW cavities exhibit behavior similar to under-coupled TW cavities.
Conclusions:
- The interplay between direct and indirect couplings offers precise control over coupled cavity transmission.
- Configurable transmission spectra are possible, with applications in nanophotonic devices.
- The findings provide valuable insights for designing advanced optical components.
Related Concept Videos
01:28Standing Waves in a Cavity
A household microwave and lasers are examples of standing electromagnetic waves in a cavity. When two conducting metal plates are placed parallel at the nodal planes, it creates a cavity where standing waves are formed. The cavity between the two planes is analogous to a stretched string held at the points x = 0 and x = L. Here, the distance 'L' between the two planes must be an integer multiple of half of the wavelength. The wavelengths that satisfy this condition are given by:
01:13¹H NMR: Complex Splitting
A proton M that is coupled to a proton X results in doublet signals for M. However, NMR-active nuclei can be simultaneously coupled to more than one nonequivalent nucleus. When M is coupled to a second proton A, such as in styrene oxide, each peak in the doublet is split into another doublet.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
01:04Modes of Standing Waves: II
The starting point for expressing the modes of standing waves is understanding the boundary conditions that the waves must follow. The boundary conditions are derived from the physical understanding of how the standing waves are sustained, that is, how the vibrating particles of the medium behave at the boundaries imposed on them.
For a tube open at one end and closed at the other filled with air, the modes are such that there is always an antinode at the open end and a node at the closed end.
For a tube open at one end and closed at the other filled with air, the modes are such that there is always an antinode at the open end and a node at the closed end.
01:13¹H NMR Signal Multiplicity: Splitting Patterns
When protons A and X are coupled, their nuclear spin energy levels are slightly modified. This is because the energy required to excite proton A to a spin state parallel to proton X is slightly different from the energy required for it to become anti-parallel to spin X. Consequently, there are two possible excitation frequencies for A (A1 and A2), depending on the spin state of X, and vice versa. The mutual nature of coupling implies that the difference between frequencies A1 and A2, indicated...
01:27¹H NMR: Long-Range Coupling
The coupling interactions of nuclei across four or more bonds are usually weak, with J values less than 1 Hz. While these are usually not observed in spectra, the presence of multiple bonds along the coupling pathway can result in observable long-range coupling.
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene π orbitals.
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene π orbitals.
01:12Double Resonance Techniques: Overview
Double resonance techniques in Nuclear Magnetic Resonance (NMR) spectroscopy involve the simultaneous application of two different frequencies or radiofrequency pulses to manipulate and observe two distinct nuclear spins. One important application of double resonance is spin decoupling, which selectively suppresses coupling with one type of nucleus while observing the NMR signal from another nucleus, simplifying the spectrum and enhancing resolution.
Spin decoupling is usually achieved by...
Spin decoupling is usually achieved by...