Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Bulletin of the American Physical Society

High resolution measurement of the {sup 3}He normal fluid Larmor frequency

Thomas M. Haard, D.M. Sprague, Jan B. Kycia

Published Apr 1, 1995• 0 citations
OpenAlex

Abstract

The authors have made high resolution magnetic resonance measurements of the {sup 3}He normal Fermi liquid Larmor frequency. At high temperatures, the Larmor frequency is temperature independent. At lower temperatures the authors observe a negative shift from this value that is approximately proportional to the inverse temperature, increasing to a maximum shift of order 1/10{sup 6} at the superfluid transition temperature ({approx} 1mK). The dependence of this shift on pressure (over the range 0.3 to 28.8 bar) and magnetic field, (0.04 and 0.12 T) is discussed.

Related papers

Stable circulation in superfluid [sup 3]He-A

Rena J. Zieve, Yury Mukharsky, J. D. Close +2 more

The authors present evidence of stable nonzero circulation in superfluid [sup 3]He-A around a 16[mu]m diameter wire. The measurements are made on a rotating cryostat at T [approx] 0.15[Tc]. Circulation affects the splitting of the wire's normal modes, which changes the beat frequency in the emf across the wire as it vibrates in a magnetic field. The different beat frequencies at 14 and at 21 bar suggest that circulation is present at 21 bar. Furthermore, at 21 bar the beat frequency is a linear function of rotation velocity, as is expected if circulation is trapped around the wire. At 14 bar no effect of rotation is observed. The authors propose that at 21 bar the ground state texture has nonzero circulation of order h/2m[sub 3].

•Oct 1, 1992•0 citations

Nuclear Paramagnetic Susceptibility of Low-Temperature He3 and the Flow Properties of superfluid Systems of Fermions

Ronald M. Rockmore

The magnetic susceptibility of He/sup 3/ as a possible test of a low- temperature phase transition in liquid He/sup 3/ to a highly correlated phase is calculated on the basis of the two-fluid model of superfluid many-fermion systems. It is concluded that the joint measurement of the moment of inertia of a cylindrical container of liquid He/sup 3/ and magnetic suscepti bility determine the effective mass for flow in the asymmetric case. (D.L.C.)

Physical Review Letters•Feb 15, 1961•0 citations

Spectral Response and Contact of the Unitary Fermi Gas

Biswaroop Mukherjee, Parth Patel, Zhenjie Yan +3 more

We measure radio frequency (rf) spectra of the homogeneous unitary Fermi gas at temperatures ranging from the Boltzmann regime through quantum degeneracy and across the superfluid transition. For all temperatures, a single spectral peak is observed. Its position smoothly evolves from the bare atomic resonance in the Boltzmann regime to a frequency corresponding to nearly one Fermi energy at the lowest temperatures. At high temperatures, the peak width reflects the scattering rate of the atoms, while at low temperatures, the width is set by the size of fermion pairs. Above the superfluid transition, and approaching the quantum critical regime, the width increases linearly with temperature, indicating non-Fermi-liquid behavior. From the wings of the rf spectra, we obtain the contact, quantifying the strength of short-range pair correlations. We find that the contact rapidly increases as the gas is cooled below the superfluid transition.

arXiv:1902.08548•Physical Review Letters•May 23, 2019•95 citations

Spin Susceptibility above the Superfluid Onset in Ultracold Fermi Gases

Yun Long, Feng Xiong, Colin Parker

Ultracold atomic Fermi gases can be tuned to interact strongly, which produces a display of spectroscopic signatures above the superfluid transition reminiscent of the pseudogap in cuprates. However, the extent of the analogy can be questioned since many thermodynamic quantities in the low temperature spin-imbalanced normal state can be described successfully using Fermi liquid theory. Here we present spin susceptibility measurements across the interaction strength-temperature phase diagram using a novel radio frequency technique with ultracold ^{6}Li gases. For all significant interaction strengths and at all temperatures we find the spin susceptibility is reduced compared to the equivalent value for a noninteracting Fermi gas. At unitarity, we can use the local density approximation to extract the integrated spin susceptibility for the uniform gas as a function of temperature, which at high temperatures is generally less than theoretically predicted. At low temperatures, our data lie within the range of theoretical predictions, although we can also describe the entire curve using a very simple one-parameter mean field model with monotonically increasing spin susceptibility.

arXiv:2011.05256•Physical Review Letters•Apr 14, 2021•12 citations

Spin Waves in Liquid He3 - He4 Mixtures

John R. Owers-Bradley, H. Chocholacs, R. M. Mueller +3 more

Continuous-wave nuclear magnetic resonance measurements have been performed on liquid $^{3}\mathrm{He}$-$^{4}\mathrm{He}$ mixtures of 5.0% (at 0, 10, and 20 bars) and 9.5% (at 10 bars) $^{3}\mathrm{He}$ between 0.3 and 25 mK. In the collisionless regime the NMR line is observed to shift and have a maximum in width, effects attributable to spin-wave excitations in the mixture and the first direct evidence for the existence of collective excitations in the $^{3}\mathrm{He}$-$^{4}\mathrm{He}$ Fermi systems. Analysis of the data yields the Fermi-liquid parameter ${{F}_{1}}^{a}$ for the 5%-$^{3}\mathrm{He}$ mixture.

Physical Review Letters•Dec 5, 1983•112 citations

Superfluid 3He

T. Tsuneto

Superfluidity in liquid 3 He, discovered in 1972, is due to pairing, as is the case for superconductivity in ordinary metals. However, the pair is in the 3 P state so that a new aspect of superfluidity appears with internal degrees of freedom. It offers quite an interesting real example of ‘spontaneous symmetry breaking’. This aspect will be emphasised in the following discussion. Fermi liquid 3 He A 3 He atom is a fermion with nuclear spin ½. Although 3 He gas liquefies at low temperatures due to the weak van der Waals force, it does not solidify even at T = 0 unless the pressure exceeds 33.5 atm (3.4 × 10 6 Pa) as shown in the phase diagram (Fig. 6.1 (a)). While Bose liquid 4 He becomes superfluid at about 2K, 3 He is Fermi-degenerate at less than T F ∼ 0.1 K and shows the properties of a normal Fermi gas. For example, the specific heat and the susceptibility are proportional to T at T < T F . It is only at an ultra-low temperature in the mK-region that the system undergoes a transition to the superfluid state. Figure 6.1(b) is the phase diagram showing the superfluid phases with variables T,P and external magnetic field H in the mK-region. It should be noted that there are two thermodynamically distinct phases called the A phase and the B phase even at H = 0, and that for H ≠ 0 the A 1 phase appears.

Cambridge University Press eBooks•Dec 10, 1998•0 citations
The authors have made high resolution magnetic resonance measurements of the {sup 3}He normal Fermi liquid Larmor frequency. At high temperatures, the Larmor frequency is temperature independent. At lower temperatures the authors observe a negative shift from this value that is approximately proportional to the inverse temperature, increasing to a maximum shift of order 1/10{sup 6} at the superfluid transition temperature ({approx} 1mK). The dependence of this shift on pressure (over the range 0.3 to 28.8 bar) and magnetic field, (0.04 and 0.12 T) is discussed.
The authors present evidence of stable nonzero circulation in superfluid [sup 3]He-A around a 16[mu]m diameter wire. The measurements are made on a rotating cryostat at T [approx] 0.15[Tc]. Circulation affects the splitting of the wire's normal modes, which changes the beat frequency in the emf across the wire as it vibrates in a magnetic field. The different beat frequencies at 14 and at 21 bar suggest that circulation is present at 21 bar. Furthermore, at 21 bar the beat frequency is a linear function of rotation velocity, as is expected if circulation is trapped around the wire. At 14 bar no effect of rotation is observed. The authors propose that at 21 bar the ground state texture has nonzero circulation of order h/2m[sub 3].
We measure radio frequency (rf) spectra of the homogeneous unitary Fermi gas at temperatures ranging from the Boltzmann regime through quantum degeneracy and across the superfluid transition. For all temperatures, a single spectral peak is observed. Its position smoothly evolves from the bare atomic resonance in the Boltzmann regime to a frequency corresponding to nearly one Fermi energy at the lowest temperatures. At high temperatures, the peak width reflects the scattering rate of the atoms, while at low temperatures, the width is set by the size of fermion pairs. Above the superfluid transition, and approaching the quantum critical regime, the width increases linearly with temperature, indicating non-Fermi-liquid behavior. From the wings of the rf spectra, we obtain the contact, quantifying the strength of short-range pair correlations. We find that the contact rapidly increases as the gas is cooled below the superfluid transition.
Ultracold atomic Fermi gases can be tuned to interact strongly, which produces a display of spectroscopic signatures above the superfluid transition reminiscent of the pseudogap in cuprates. However, the extent of the analogy can be questioned since many thermodynamic quantities in the low temperature spin-imbalanced normal state can be described successfully using Fermi liquid theory. Here we present spin susceptibility measurements across the interaction strength-temperature phase diagram using a novel radio frequency technique with ultracold ^{6}Li gases. For all significant interaction strengths and at all temperatures we find the spin susceptibility is reduced compared to the equivalent value for a noninteracting Fermi gas. At unitarity, we can use the local density approximation to extract the integrated spin susceptibility for the uniform gas as a function of temperature, which at high temperatures is generally less than theoretically predicted. At low temperatures, our data lie within the range of theoretical predictions, although we can also describe the entire curve using a very simple one-parameter mean field model with monotonically increasing spin susceptibility.
Continuous-wave nuclear magnetic resonance measurements have been performed on liquid 3He^{3}\mathrm{He}3He-4He^{4}\mathrm{He}4He mixtures of 5.0% (at 0, 10, and 20 bars) and 9.5% (at 10 bars) 3He^{3}\mathrm{He}3He between 0.3 and 25 mK. In the collisionless regime the NMR line is observed to shift and have a maximum in width, effects attributable to spin-wave excitations in the mixture and the first direct evidence for the existence of collective excitations in the 3He^{3}\mathrm{He}3He-4He^{4}\mathrm{He}4He Fermi systems. Analysis of the data yields the Fermi-liquid parameter F1a{{F}_{1}}^{a}F1​a for the 5%-3He^{3}\mathrm{He}3He mixture.
Superfluidity in liquid 3 He, discovered in 1972, is due to pairing, as is the case for superconductivity in ordinary metals. However, the pair is in the 3 P state so that a new aspect of superfluidity appears with internal degrees of freedom. It offers quite an interesting real example of ‘spontaneous symmetry breaking’. This aspect will be emphasised in the following discussion. Fermi liquid 3 He A 3 He atom is a fermion with nuclear spin ½. Although 3 He gas liquefies at low temperatures due to the weak van der Waals force, it does not solidify even at T = 0 unless the pressure exceeds 33.5 atm (3.4 × 10 6 Pa) as shown in the phase diagram (Fig. 6.1 (a)). While Bose liquid 4 He becomes superfluid at about 2K, 3 He is Fermi-degenerate at less than T F ∼ 0.1 K and shows the properties of a normal Fermi gas. For example, the specific heat and the susceptibility are proportional to T at T < T F . It is only at an ultra-low temperature in the mK-region that the system undergoes a transition to the superfluid state. Figure 6.1(b) is the phase diagram showing the superfluid phases with variables T,P and external magnetic field H in the mK-region. It should be noted that there are two thermodynamically distinct phases called the A phase and the B phase even at H = 0, and that for H ≠ 0 the A 1 phase appears.