Identical Spin Rotation Effect and Electron Spin Waves in Quantum Gas of Atomic Hydrogen

Abstract

We present an experimental study of electron spin waves in atomic hydrogen gas compressed to high densities of $\sim 5\times 10^{18}$ cm${}^{-3}$ at temperatures ranging from 0.26 to 0.6 K in strong magnetic field of 4.6 T. Hydrogen gas is in a quantum regime when the thermal de Broglie wavelength is much larger than the s-wave scattering length. In this regime the identical particle effects play major role in atomic collisions and lead to the Identical Spin Rotation effect (ISR). We observed a variety of spin wave modes caused by this effect with strong dependence on the magnetic potential caused by variations of the polarizing magnetic field. We demonstrate confinement of the ISR modes in the magnetic potential and manipulate their properties by changing the spatial profile of magnetic field. We have found that at a high enough density of H gas the magnons accumulate in their ground state in the magnetic trap and exhibit long coherence, which has a profound effect on the electron spin resonance spectra. Such macroscopic accumulation of the ground state occurs at a certain critical density of hydrogen gas, where the chemical potential of the magnons becomes equal to the energy of their ground state in the trapping potential.

arXiv comment16 pages, 15 figures

References in corpus (5)

• Bose-Einstein condensation of photons in an optical microcavity
• Spatial resolution of spin waves in an ultra-cold gas
• Self-localization of magnon Bose-Einstein condensates in the ground state and on excited levels: from harmonic to box-like trapping potential
• Bose-Einstein condensation of magnons in atomic hydrogen gas
• Guiding and Trapping Electron Spin Waves in Atomic Hydrogen Gas

Cited by in corpus (2)

• Heisenberg's uncertainty principle in the PTOLEMY project: a theory update
• Searching for Magnetostatic Modes in Spin-Polarized Atomic Hydrogen