High-Precision Optical Measurement of the2SHyperfine Interval in Atomic Hydrogen

High Precision Optical Measurement Methods

I. INIRODllCTION Noncontact optical methods are appropriate for mic;ro.. and macrostructure measurements. Time of flight and phase measuring techniques with a resolution in the order of a few mm to one mm. respectively arc well introduced. Furthermore active and passive triangulation techniques arc very robust and appropriate for different applications in precision measurements. Some optical 3-...

Precision measurements with atomic hydrogen masers

Atomic hydrogen as high-precision field standard for high-field EPR.

We introduce atomic hydrogen trapped in an octaisobutylsilsesquioxane nanocage (H@iBuT₈) as a new molecular high-precision magnetic field standard for high-field EPR spectroscopy of organic radicals and other systems with signals around g=2. Its solid-state EPR spectrum consists of two 0.2 mT wide lines separated by about 51 mT and centered at g≈2. The isotropic g factor is 2.00294(3) and essen...

High-temperature superconductivity in atomic metallic hydrogen

Superconductivity in the recently proposed ground-state structures of atomic metallic hydrogen is calculated over the pressure range 500 GPa to 3.5 TPa. Near molecular dissociation, the electron-phonon coupling λ and renormalized Coulomb repulsion are similar to the molecular phase. A nearly continuous increase in the critical temperature Tc with pressure is thus predicted in this range, to ∼35...

A Boost in Precision for Optical Atomic Clocks

T oday’s most precise atomic clocks are based on strontium, ytterbium, and other alkaline-earth (or alkaline-earth-like) atoms [1]. These elements have ultranarrow transitions at optical frequencies, providing stable and precise frequency standards for measuring time, as does the quartz oscillator in a wristwatch. Alkalineearth frequency standards are almost a thousandfold more precise than the...