Related Experiment Video
Updated: Jun 8, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Quantum-fluctuation-initiated coherence in multioctave Raman optical frequency combs
Y Y Wang1, Chunbai Wu, F Couny
1Gas-Phase Photonic Materials Group, CPPM, Physics Department, University of Bath, BA27AY, United Kingdom.
Physical Review Letters
|September 28, 2010
Summary
Researchers demonstrate that spectral components of a spontaneously generated multioctave frequency comb are highly coherent. This optical frequency comb, created via stimulated Raman scattering, shows potential for nonclassical correlations between comb lines.
Area of Science:
- Quantum optics
- Nonlinear optics
- Fiber optics
Background:
- Spontaneous generation of multioctave frequency combs via stimulated Raman scattering (SRS) is a complex process.
- Understanding the coherence properties of these combs is crucial for their applications.
Purpose of the Study:
- To experimentally and theoretically investigate the coherence of spectral components in a spontaneously created multioctave frequency comb.
- To explore the origin of coherence despite initiation from quantum zero-point fluctuations.
Main Methods:
- Experimental generation of a frequency comb using SRS in a hydrogen-filled hollow-core photonic crystal fiber.
- Theoretical analysis of spectral component coherence and phase/energy fluctuations.
Main Results:
- Demonstrated strong self-coherence and mutual coherence of spectral components within each driving laser pulse.
- Observed that coherence persists despite initial quantum fluctuations.
Conclusions:
- The findings indicate a robust coherence mechanism in spontaneously generated frequency combs.
- Suggests the potential for developing optical frequency combs with nonclassical correlations between all comb lines.
Related Concept Videos
01:26Raman Spectroscopy Instrumentation: Overview
A conventional Raman spectrophotometer includes a laser source, a sample holding system, a wavelength selector, and a detector.
The monochromatic laser source, typically using visible or near-infrared radiation, generates a highly focused beam of light. This light interacts with the molecules of the sample, scattering some of the light. Liquid and gaseous samples are usually tested in ordinary glass capillaries, while solids can be analyzed as powders packed in capillaries or as potassium...
The monochromatic laser source, typically using visible or near-infrared radiation, generates a highly focused beam of light. This light interacts with the molecules of the sample, scattering some of the light. Liquid and gaseous samples are usually tested in ordinary glass capillaries, while solids can be analyzed as powders packed in capillaries or as potassium...
01:20Raman Spectroscopy: Overview
The underlying principle of Raman spectroscopy is based on the interaction between light and matter, specifically molecules' inelastic scattering of photons. When a monochromatic beam of light, typically from a laser source, interacts with a sample, most scattered light has the same frequency as the incident light. This is known as Rayleigh scattering.
However, a small fraction of the scattered light exhibits a frequency shift due to the exchange of energy between the incident photons and the...
However, a small fraction of the scattered light exhibits a frequency shift due to the exchange of energy between the incident photons and the...
01:24IR Spectroscopy: Molecular Vibration Overview
When Infrared (IR) radiation passes through a covalently bonded molecule, the bonds transition from lower to higher vibrational levels. The fundamental vibrational motions that result in infrared absorption can be classified as stretching or bending vibrations.
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
01:16IR Spectroscopy: Hooke's Law Approximation of Molecular Vibration
A covalently bonded heteronuclear diatomic molecule can be modeled as two vibrating masses connected by a spring. The vibrational frequency of the bond can be expressed using an equation derived from Hooke's law, which describes how the force applied to stretch or compress a spring is proportional to the displacement of the spring. In this case, the atoms behave like masses, and the bond acts like a spring.
According to Hooke's law, the vibrational frequency is directly proportional to the...
According to Hooke's law, the vibrational frequency is directly proportional to the...
01:16UV–Vis Spectroscopy: Molecular Electronic Transitions
In Ultraviolet–Visible (UV–Vis) spectroscopy, the absorption of electromagnetic radiation is used to probe the electronic structure of molecules. This technique provides insights into molecular electronic transitions, particularly the movement of electrons between different molecular orbitals. Radiation is absorbed if the energy of the electromagnetic radiation passing through the molecule is precisely equal to the energy difference between the excited and ground states. During this process,...
01:21IR Absorption Frequency: Hybridization
Hydrocarbons such as alkanes, alkenes, and alkynes show characteristic C–H stretching absorption bands. These IR stretching frequencies depend on the hybridization of the involved carbon atom and can be explained in terms of the s character of each hybridized atomic orbital.
Among the sp, sp2, and sp3 hybridized orbitals, sp orbitals have the maximum s character (50%). Consequently, the electrons are held more closely to the nucleus, resulting in stronger and shorter C–H bonds that stretch at a...
Among the sp, sp2, and sp3 hybridized orbitals, sp orbitals have the maximum s character (50%). Consequently, the electrons are held more closely to the nucleus, resulting in stronger and shorter C–H bonds that stretch at a...