Related Experiment Video
Updated: Jan 31, 2026
09:20
Live Cell Response to Mechanical Stimulation Studied by Integrated Optical and Atomic Force Microscopy
Published on: October 4, 2010
11.7K
Observation of Ultrastrong Spin-Motion Coupling for Cold Atoms in Optical Microtraps
A Dareau1, Y Meng1, P Schneeweiss1
1Vienna Center for Quantum Science and Technology, TU Wien-Atominstitut, Stadionallee 2, 1020 Vienna, Austria.
Physical Review Letters
|January 5, 2019
Summary
Researchers created a Dicke model analog using neutral atoms, coupling their spin to motion in optical traps. This system achieves ultrastrong coupling, enabling new applications in quantum physics.
Area of Science:
- Atomic Physics
- Quantum Optics
- Condensed Matter Physics
Background:
- The Dicke model describes collective phenomena in quantum optics and condensed matter.
- Implementing the Dicke model with controllable coupling strengths is crucial for quantum technologies.
Purpose of the Study:
- To create a mechanical analog of the Dicke model using individual neutral atoms.
- To experimentally achieve and tune ultrastrong coupling regimes.
Main Methods:
- Coupling atomic spin states to quantized motional states in optical traps.
- Utilizing polarization gradients in trapping light fields to induce spin-motion coupling.
- Employing an additional light field for in situ coupling strength tuning.
Main Results:
- Demonstrated a one-to-one mapping between the atomic system and the Dicke model.
- Achieved ultrastrong coupling, with coupling strength as a significant fraction of the trap frequency.
- Showcased in situ tunability of the coupling strength.
Conclusions:
- The developed system serves as a robust mechanical analog of the Dicke model.
- This platform opens avenues for exploring quantum phenomena at extreme coupling strengths.
- Potential applications in quantum simulation and information processing exploiting these extreme couplings.
Related Concept Videos
01:17Spin–Spin Coupling: One-Bond Coupling
1.5K
Coupling interactions are strongest between NMR-active nuclei bonded to each other, where spin information can be transmitted directly through the pair of bonding electrons. While nuclei polarize their electrons to the opposite spins, the bonding electron pair has opposite spins. Configurations with antiparallel nuclear spins are expected to be lower in energy. When coupling makes antiparallel states more favorable, J is considered to have a positive value. The one-bond coupling constant, 1J,...
1.5K
01:20Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
1.7K
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
1.7K
01:22Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)
1.5K
Vicinal or three-bond coupling is commonly observed between protons attached to adjacent carbons. Here, nuclear spin information is primarily transferred via electron spin interactions between adjacent C‑H bond orbitals. This generally favors the antiparallel arrangement of spins, so 3J values are usually positive.
The extent of coupling depends on the C‑C bond length, the two H‑C‑C angles, any electron-withdrawing substituents, and the dihedral angle between the involved orbitals. The...
The extent of coupling depends on the C‑C bond length, the two H‑C‑C angles, any electron-withdrawing substituents, and the dihedral angle between the involved orbitals. The...
1.5K
01:08NMR Spectroscopy: Spin–Spin Coupling
3.2K
The spin state of an NMR-active nucleus can have a slight effect on its immediate electronic environment. This effect propagates through the intervening bonds and affects the electronic environments of NMR-active nuclei up to three bonds away; occasionally, even farther. This phenomenon is called spin–spin coupling or J-coupling. Coupling interactions are mutual and result in small changes in the absorption frequencies of both nuclei involved. While nuclei of the same element are involved...
3.2K
01:08Spin–Spin Coupling Constant: Overview
1.5K
In bromoethane, the three methyl protons are coupled to the two methylene protons that are three bonds away. In accordance with the n+1 rule, the signal from the methyl protons is split into three peaks with 1:2:1 relative intensities. The methylene protons appear as a quartet, with the relative intensities of 1:3:3:1.
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
1.5K
01:08Atomic Nuclei: Nuclear Spin
5.1K
All atomic particles possess an intrinsic angular momentum, or 'spin'. Electrons, protons, and neutrons each have a spin value of ½, although protons and neutrons in nuclei may have higher half-integer spins owing to energetic factors.
Atomic nuclei have a net nuclear spin, , which can have an integer or half-integer value. In atomic nuclei, the spins of protons are paired against each other but not with neutrons, and vice versa. Consequently, an even number of protons does not contribute to...
Atomic nuclei have a net nuclear spin, , which can have an integer or half-integer value. In atomic nuclei, the spins of protons are paired against each other but not with neutrons, and vice versa. Consequently, an even number of protons does not contribute to...
5.1K