Related Experiment Video
Updated: Jan 30, 2026
12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
17.5K
Control of resonance mode using a fine-structured grating: toward a high resolving power filter
Applied Optics
|January 30, 2019
Summary
This study presents a novel mid-infrared band-stop filter using gold nanowires for high-resolution spectroscopic sensing. The filter achieves narrow bandwidth and high extinction, enabling precise spectral analysis.
Area of Science:
- Photonics and Nanotechnology
- Spectroscopic Sensing
- Mid-Infrared Optics
Background:
- Mid-infrared spectroscopy and imaging require filters with high resolving power.
- Existing filters may face limitations in bandwidth compression and resonance extinction.
Purpose of the Study:
- To design and demonstrate a band-stop filter with high spectral resolving power for mid-infrared applications.
- To achieve simultaneous compression of stop bandwidth and improvement of resonance extinction.
Main Methods:
- Utilized a truncated grating structure composed of multiple gold nanowires per unit cell.
- Investigated the flexible control of filtering performance by adjusting geometrical parameters.
Main Results:
- Achieved a single stop band at approximately 4.474 μm with 15 dB extinction.
- Demonstrated >80% background transmission over a wide spectral range.
- Obtained a narrow linewidth of ~1.45 nm, resulting in a spectral resolving power >3000.
Conclusions:
- The designed filter offers high resolving power for mid-infrared spectroscopic sensing and imaging.
- The structure shows potential for refractive index sensing applications.
- The nanostructure provides a flexible platform for tunable optical filtering.
Related Concept Videos
01:30Control of Power Flow
693
There are several methods to control power flow in power systems:
693
02:16Resonance and Hybrid Structures
26.3K
According to the theory of resonance, if two or more Lewis structures with the same arrangement of atoms can be written for a molecule, ion, or radical, the actual distribution of electrons is an average of that shown by the various Lewis structures.
Resonance Structures and Resonance Hybrids
The Lewis structure of a nitrite anion (NO2−) may actually be drawn in two different ways, distinguished by the locations of the N–O and N=O bonds.
Resonance Structures and Resonance Hybrids
The Lewis structure of a nitrite anion (NO2−) may actually be drawn in two different ways, distinguished by the locations of the N–O and N=O bonds.
26.3K
02:52Resonance
65.1K
The Lewis structure of a nitrite anion (NO2−) may actually be drawn in two different ways, distinguished by the locations of the N-O and N=O bonds.
65.1K
01:27Passive Filters
1.0K
Passive filters are utilized to shape the frequency spectrum of signals across a diverse array of applications. These filters, using only passive elements like resistors (R), inductors (L), and capacitors (C), are capable of selectively allowing or blocking certain frequency ranges without the need for external power sources.
Low-Pass Filters
Low-pass filters are designed to transmit signals with frequencies lower than the cutoff frequency, ωc, and attenuate those above it. The cutoff...
Low-Pass Filters
Low-pass filters are designed to transmit signals with frequencies lower than the cutoff frequency, ωc, and attenuate those above it. The cutoff...
1.0K
01:07What is a Mode?
26.0K
The mode is one of the commonly used measures of a central tendency. It is defined as the most frequent value in a data set.
There can be more than one mode in a data set if multiple values have the same highest frequency. For instance, suppose that the Statistics exam scores of 20 students are: 50; 53; 59; 59; 63; 63; 72; 72; 72; 72; 72; 76; 78; 81; 83; 84; 84; 84; 90; 93. Here, the mode is 72, as it occurs most frequently, five times.
A data set with two modes is called bimodal. For example,...
There can be more than one mode in a data set if multiple values have the same highest frequency. For instance, suppose that the Statistics exam scores of 20 students are: 50; 53; 59; 59; 63; 63; 72; 72; 72; 72; 72; 76; 78; 81; 83; 84; 84; 84; 90; 93. Here, the mode is 72, as it occurs most frequently, five times.
A data set with two modes is called bimodal. For example,...
26.0K
01:25Active Filters
1.3K
Active filters are electronic circuits that use operational amplifiers (op-amps), resistors, and capacitors to filter out unwanted frequency components from a signal. A first-order low-pass active filter is designed to pass signals with a frequency lower than a certain cutoff frequency and attenuate frequencies higher than that cutoff frequency. The transfer function for a first-order low-pass active filter is:
1.3K