Related Experiment Video
Updated: Jun 8, 2026
08:22
Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Probing the Fulde-Ferrell-Larkin-Ovchinnikov phase by double occupancy modulation spectroscopy
Anna Korolyuk1, Francesco Massel, Päivi Törmä
1Department of Applied Physics, P.O. Box 15100, 00076 Aalto University, Finland.
Physical Review Letters
|September 28, 2010
Summary
Researchers propose observing changes in double occupancy due to lattice modulation can detect the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase. Numerical simulations show a narrowing spectrum width with increasing imbalance, linked to the FFLO wave vector.
Area of Science:
- Quantum physics
- Condensed matter physics
- Ultracold atomic gases
Background:
- Investigating spin-imbalanced Fermi gases in optical lattices is crucial for understanding emergent quantum phases.
- The Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase is a theoretically predicted exotic superconducting state.
Purpose of the Study:
- To propose a new experimental method for detecting the FFLO phase in a spin-imbalanced Fermi gas.
- To characterize the spectral properties of double occupancy in response to lattice modulation.
Main Methods:
- Numerical simulations of the time evolution of a two-component Fermi gas in a 1D optical lattice.
- Analysis of the double occupancy spectrum under varying spin imbalance and lattice depth modulation.
- Application of Bethe-ansatz equations in the strongly interacting limit.
Main Results:
- A striking narrowing of the double occupancy spectrum width was observed with increasing spin imbalance.
- This spectral narrowing is shown to be directly related to the FFLO wave vector (q).
Conclusions:
- Lattice depth modulation provides a clear experimental signature for detecting the FFLO phase.
- The observed spectral narrowing serves as a direct probe of the FFLO wave vector, confirming the phase's presence.
Related Concept Videos
01:16UV–Vis Spectroscopy: Molecular Electronic Transitions
In Ultraviolet–Visible (UV–Vis) spectroscopy, the absorption of electromagnetic radiation is used to probe the electronic structure of molecules. This technique provides insights into molecular electronic transitions, particularly the movement of electrons between different molecular orbitals. Radiation is absorbed if the energy of the electromagnetic radiation passing through the molecule is precisely equal to the energy difference between the excited and ground states. During this process,...
01:02¹H NMR: Interpreting Distorted and Overlapping Signals
Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...
01:12Double Resonance Techniques: Overview
Double resonance techniques in Nuclear Magnetic Resonance (NMR) spectroscopy involve the simultaneous application of two different frequencies or radiofrequency pulses to manipulate and observe two distinct nuclear spins. One important application of double resonance is spin decoupling, which selectively suppresses coupling with one type of nucleus while observing the NMR signal from another nucleus, simplifying the spectrum and enhancing resolution.
Spin decoupling is usually achieved by...
Spin decoupling is usually achieved by...
01:14Molecular Spectroscopy: Absorption and Emission
Molecules possess discrete energy levels called quantum states. Unlike atoms, which have simpler energy levels, molecules possess additional rotational and vibrational energy levels. Each energy level is separated by an energy gap, with the gaps between adjacent electronic, vibrational, and rotational levels varying significantly. The three types of energy levels in a diatomic molecule are shown in Figure 1.
01:20¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
When proton-coupled carbon-13 spectra are simplified by a broadband proton decoupling technique, structural information about the coupled protons is lost. Distortionless enhancement by polarization transfer (DEPT) is a technique that provides information on the number of hydrogens attached to each carbon in a molecule. While the DEPT experiment utilizes complex pulse sequences, the pulse delay and flip angle are specifically manipulated. The resulting signals have different phases depending on...
01:13¹H NMR: Complex Splitting
A proton M that is coupled to a proton X results in doublet signals for M. However, NMR-active nuclei can be simultaneously coupled to more than one nonequivalent nucleus. When M is coupled to a second proton A, such as in styrene oxide, each peak in the doublet is split into another doublet.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.