Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

The Bohr Model02:18

The Bohr Model

Following the work of Ernest Rutherford and his colleagues in the early twentieth century, the picture of atoms consisting of tiny dense nuclei surrounded by lighter and even tinier electrons continually moving about the nucleus was well established. This picture was called the planetary model since it pictured the atom as a miniature “solar system” with the electrons orbiting the nucleus like planets orbiting the sun. The simplest atom is hydrogen, consisting of a single proton as the nucleus...
Subatomic Particles03:37

Subatomic Particles

Dalton was only partially correct about the particles that make up matter. All matter is composed of atoms, and atoms are composed of three smaller subatomic particles: protons, neutrons, and electrons. These three particles account for the mass and the charge of an atom.
High-Resolution Mass Spectrometry (HRMS)01:15

High-Resolution Mass Spectrometry (HRMS)

The resolution of a mass spectrometer depends on the efficiency of separating ions with different ion masses. The mass of an atom is approximated to the sum of the masses of protons and neutrons inside, considering the masses of protons and neutrons as equal. However, the masses of the proton (1.6726 × 10−24 g) and neutron (1.6749 × 10−24 g) are not truly equal. There is a minor error in the expression of atomic masses relative to the simplest atom of hydrogen. For example, the mass of helium...
Atomic Nuclei: Larmor Precession Frequency01:11

Atomic Nuclei: Larmor Precession Frequency

The earth's gravitational field produces a 'twisting force' perpendicular to the angular momentum of a spinning mass (such as a spinning top) that causes the mass to 'wobble' around the gravitational field axis in a phenomenon called precession. Similarly, the magnetic moment (μ) of a spinning nucleus precesses due to an external magnetic field directed along the z-axis. The precession of the magnetic moment vector about the magnetic field is called Larmor precession, and the angular frequency...
Atomic Mass01:52

Atomic Mass

Atoms — and the protons, neutrons, and electrons that compose them — are extremely small. For example, a carbon atom weighs less than 2 × 10−23 g. When describing the properties of tiny objects such as atoms, we use appropriately small units of measure, such as the atomic mass unit (amu). The amu was originally defined based on hydrogen, the lightest element, then later in terms of oxygen. Since 1961, it has been defined with regard to the most abundant isotope of carbon, atoms of which are...
The Uncertainty Principle04:08

The Uncertainty Principle

Werner Heisenberg considered the limits of how accurately one can measure properties of an electron or other microscopic particles. He determined that there is a fundamental limit to how accurately one can measure both a particle’s position and its momentum simultaneously. The more accurate the measurement of the momentum of a particle is known, the less accurate the position at that time is known and vice versa. This is what is now called the Heisenberg uncertainty principle. He mathematically...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Evidence of Spin-Interference Effects in Exclusive J/ψ→e^{+}e^{-} Photoproduction in Ultraperipheral Heavy-Ion Collisions.

Physical review letters·2026
Same author

First Observation of Deuteron-Λ Correlations at RHIC.

Physical review letters·2026
Same author

Observation of Charmonium Sequential Suppression in Heavy-Ion Collisions at the Relativistic Heavy Ion Collider.

Physical review letters·2026
Same author

Energy Independence of the Collins Asymmetry in p^{↑}p Collisions.

Physical review letters·2026
Same author

Particle size-dependent bioaccessibility of chromium in smelting soils: assessment by multi-method in vitro simulations.

Environmental monitoring and assessment·2025
Same author

Precision Measurement of Net-Proton-Number Fluctuations in Au+Au Collisions at RHIC.

Physical review letters·2025

Related Experiment Video

Updated: May 21, 2026

In Situ Measurement of Vacuum Window Birefringence using 25Mg+ Fluorescence
07:03

In Situ Measurement of Vacuum Window Birefringence using 25Mg+ Fluorescence

Published on: June 13, 2020

Neutral atom frequency reference in the deep ultraviolet with fractional uncertainty = 5.7×10(-15).

J J McFerran1, L Yi, S Mejri

  • 1LNE-SYRTE, Observatoire de Paris, CNRS, UPMC, 61 Avenue de l'Observatoire, 75014, Paris, France. john.mcferran@obspm.fr

Physical Review Letters
|June 12, 2012
PubMed
Summary

We precisely measured the mercury-199 atomic clock transition frequency, achieving a record atomic quality factor (Q) of ~10^14. This advancement significantly enhances atomic clock accuracy for future timekeeping applications.

More Related Videos

Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
10:42

Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh

Published on: May 3, 2019

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
08:22

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization

Published on: August 6, 2018

Related Experiment Videos

Last Updated: May 21, 2026

In Situ Measurement of Vacuum Window Birefringence using 25Mg+ Fluorescence
07:03

In Situ Measurement of Vacuum Window Birefringence using 25Mg+ Fluorescence

Published on: June 13, 2020

Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
10:42

Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh

Published on: May 3, 2019

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
08:22

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization

Published on: August 6, 2018

Area of Science:

  • Atomic Physics
  • Quantum Metrology
  • Optical Atomic Clocks

Background:

  • Precise atomic transition frequencies are crucial for developing advanced atomic clocks.
  • Mercury-199 (199Hg) offers a promising candidate for optical atomic clocks due to its suitable electronic structure.
  • Previous measurements had limitations in uncertainty and atomic quality factor (Q).

Purpose of the Study:

  • To significantly reduce the uncertainty of the (6s2)(1)S0 ↔ (6s6p)(3)P0 clock transition frequency in 199Hg.
  • To demonstrate a high atomic quality factor (Q) for improved clock stability.
  • To determine the magic wavelength for lattice confinement of 199Hg atoms.

Main Methods:

  • Confined 199Hg atoms in a vertical lattice trap using a newly determined magic wavelength of 362.5697 nm.
  • Utilized a magneto-optical trap for atom loading and cooling at 253.7 nm.
  • Employed an 80 ms Rabi pulse at 265.6 nm for high-Q factor interrogation.

Main Results:

  • Achieved an atomic quality factor (Q) of approximately 10^14.
  • Measured the clock transition frequency with a fractional uncertainty of 5.7×10^-15.
  • Observed no dependence on atom number or second-order Zeeman effects.

Conclusions:

  • The study presents a highly accurate measurement of the 199Hg clock transition frequency.
  • The demonstrated high Q factor and reduced uncertainty pave the way for next-generation atomic clocks.
  • The use of only three laser wavelengths simplifies the experimental setup.