Optical microspheres (photonic atoms) are one of the types of optical
microresonators (also microcavities) employed commonly in
photonic research; they provide high
quality factor
In physics and engineering, the quality factor or ''Q'' factor is a dimensionless parameter that describes how underdamped an oscillator or resonator is. It is defined as the ratio of the initial energy stored in the resonator to the energy los ...
up to 10
11. These
optical resonator An optical cavity, resonating cavity or optical resonator is an arrangement of mirrors or other optical elements that forms a cavity resonator for light waves. Optical cavities are a major component of lasers, surrounding the gain medium and provi ...
s are used for active and passive photonic applications such as microlaser cavities and filters among many experiments that take advantage of very high levels of light confined on a small structure.
References
Photonics
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