Observation of Spin Waves in Sodium and Potassium

Abstract

Phys. Rev. Letters JL8, 283 (1967). 5 F. J. Dyson, Phys. Rev. 98, 349 (1955). 6 M. Lampe and P. M. Platzman, Phys. Rev. 150, 340 (1966). 7 In principle, an absolute measurement of the susceptibility determines the value of the isotropic exchange parameter. In practice, this measurement [R. Schumacher, T. Carver, and C. P. Slichter, Phys. Rev. 95^, 1089 (1954)] is extremely difficult to perform and gives results which necessarily have poor accuracy. 8 P. Nozieres, Theory of Interacting Fermi Systems (W. A. Benjamin, Inc., New York, 1964). 9 The mass m* is the effective quasiparticle mass which includes band-structure effects, phonons, and Using the ac Josephson effect, we have determined that 2e/h = 483.5912 ±0.0030 MHz/jxV. The implications of this measurement for quantum electrodynamics are discussed as well as its effect on our knowledge of the fundamental physical constants.

Chiral Spin Waves in Fermi Liquids with Spin-Orbit Coupling

“…With this analogy in mind, collective modes in an SO-coupled FL are somewhat similar to spin waves in a FL subject to a (real) magnetic field [8][9][10]. Spin waves occur because the exchange interaction couples precessing spins located at some distance from each other; this results in a dispersive mode which starts off at the unrenormalized (thanks to the Kohn's theorem) Larmor frequency and decreases with the wavenumber.…”

“…(8a) and (8b) via m i = 1/2D i , E i = Ω 2 i , and V i (r) = ∆ 2 (r)(1 + F a 0 δ i ) are the "potential energies", which we now allow to vary slowly (compared to the electron wavelength) in the 2DEG plane. The lateral variation of ∆ confines the spin-chiral modes and thus allows to extract the information about their dispersion, similar to how it was done for spin waves in He3 [9] and alkaline metals [10].…”

Spin Collective Oscillations in Two‐Dimensional Charged Fermi Liquids

“…About ten years later Platzman and Wolff [3] made the next step; they derived a theory for the main propagating spin wave mode with accuracy up to k2, where k is the wave vector of an external disturbance. With the help of their theory, Schultz and Dunifer [4] extracted from experiment values for the first two Landau parameters. Their experiment together with the Platzman-Wolff theory extended Silin's consideration to the case of propagating spin waves in a metal and became the basis of a new spectroscopic method in metal physics.…”

Spin modes in electron Fermi liquid of organic conductors

“…At present paper we study the collective modes arising from the oscillations of the spin density in layered structures. The paramagnetic spin waves in quasi-isotropic metals were predicted by Silin [3] and observed in alkaline metals by Dunifer and Schultz [4]. The wave processes in layered conductors are characterized by a number of features associated with the quasi-two-dimensional electron energy spectrum.…”