We observe spin rotations caused by atomic collisions in a nonequilibrium Bose-condensed gas of ^{87}Rb. Reflection from a pseudomagnetic barrier creates counterflow in which forward- and backward-propagating matter waves have partly transverse spin directions. Even though inter-atomic interaction strengths are state independent, the indistinguishability of parallel spins leads to spin dynamics. A local magnetodynamic model, which captures the salient features of the observed spin textures, highlights an essential connection between four-wave mixing and collisional spin rotation. The observed phenomenon is commonly thought not to occur in Bose condensates; our observations and model clarify the nature of these effective-magnetic spin rotations.

Download full-text PDF

Source
http://dx.doi.org/10.1103/PhysRevLett.132.173401DOI Listing

Publication Analysis

Top Keywords

spin rotations
12
spin
7
rotations bose-einstein
4
bose-einstein condensate
4
condensate driven
4
driven counterflow
4
counterflow spin-independent
4
spin-independent interactions
4
interactions observe
4
observe spin
4

Similar Publications

Weyl semimetals are a novel class of topological materials with unique electronic structures and distinct properties. HfRhGe stands out as a noncentrosymmetric Weyl semimetal with unconventional superconducting characteristics. Using muon-spin rotation and relaxation (µSR) spectroscopy and thermodynamic measurements, a fully gapped superconducting state is identified in HfRhGe that breaks time-reversal symmetry at the superconducting transition.

View Article and Find Full Text PDF

Polarization ellipses are well-known as the result of coherent superposition of photonic spin states. As orbital counterparts, in this Letter, we introduce centroid ellipses that are geometrically mapped from optical orbital angular momentum (OAM) superpositions on a modal Poincaré sphere (PS) by coaxial interference. Different from not easily observable polarization ellipses, these centroid ellipses can be directly observed from dynamical interferograms with broken rotational symmetry.

View Article and Find Full Text PDF

The nonintegrable higher spin Kitaev honeycomb model has an exact Z_{2} gauge structure, which exclusively identifies quantum spin liquid in the half-integer spin Kitaev model. But its constraints for the integer-spin Kitaev model are much limited, and even trivially gapped insulators cannot be excluded. The physical implications of exact Z_{2} gauge structure, especially Z_{2} fluxes, in integer-spin models remain largely unexplored.

View Article and Find Full Text PDF

Excited state properties from the Bethe-Salpeter equation: State-to-state transitions and spin-orbit coupling.

J Chem Phys

December 2024

Institute of Theoretical Solid State Physics, Karlsruhe Institute of Technology, Kaiserstraße 12, 76131 Karlsruhe, Germany.

The formalism to calculate excited state properties from the GW-Bethe-Salpeter equation (BSE) method is introduced, providing convenient access to excited state absorption, excited state circular dichroism, and excited state optical rotation in the framework of the GW-BSE method. This is achieved using the second-order transition density, which can be obtained by solving a set of auxiliary equations similar to time-dependent density functional theory (TD-DFT). The proposed formulation therefore leads to no increase in the formal computational complexity when compared to the corresponding ground state properties.

View Article and Find Full Text PDF

Purpose: To implement and evaluate the feasibility of brain spin-lattice relaxation in the rotating frame (T1ρ) mapping using a novel optimized pulse sequence that incorporates weighted spin-lock acquisitions, enabling high-resolution three-dimensional (3D) mapping.

Methods: The optimized variable flip-angle framework, previously proposed for knee T1ρ mapping, was enhanced by integrating weighted spin-lock acquisitions. This strategic combination significantly boosts signal-to-noise ratio (SNR) while reducing data acquisition time, facilitating high-resolution 3D-T1ρ mapping of the brain.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!