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Register a new userDynamics of a one-dimensional spinor Bose liquid: a phenomenological approach
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The ground state of a spinor Bose liquid is ferromagnetic, while the softest excitation above the ground state is the magnon mode. The dispersion relation of the magnon in a one-dimensional liquid is periodic in the wavenumber q with the period 2pi n, determined by the density n of the liquid. Dynamic correlation functions, such as e.g. spin-spin correlation function, exhibit power-law singularities at the magnon spectrum, $omegatoomega_m(q,n)$. Without using any specific model of the inter-particle interactions, we relate the corresponding exponents to independently measurable quantities $partialomega_m/partial q$ and $partialomega_m/partial n$.
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In this paper we review recent theoretical results for transport in a one-dimensional (1d) Luttinger liquid. For simplicity, we ignore electron spin, and focus exclusively on the case of a single-mode. Moreover, we consider only the effects of a single (or perhaps several) spatially localized impurities. Even with these restrictions, the predicted behavior is very rich, and strikingly different than for a 1d non-interacting electron gas. The method of bosonization is reviewed, with an emphasis on physical motivation, rather than mathematical rigor. Transport through a single impurity is reviewed from several different perspectives, as a pinned strongly interacting ``Wigner crystal and in the limit of weak interactions. The existence of fractionally charged quasiparticles is also revealed. Inter-edge tunnelling in the quantum Hall effect, and charge fluctuations in a quantum dot under the conditions of Coulomb blockade are considered as examples of the developed techniques.
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