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Fermionic Quasiparticle Representation of Tomonaga-Luttinger Hamiltonian

A. V. Rozhkov
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Abstract

We find a unitary operator which asymptotically diagonalizes the Tomonaga-Luttinger hamiltonian of one-dimensional spinless electrons. The operator performs a Bogoliubov rotation in the space of electron-hole pairs. If bare interaction of the physical electrons is sufficiently small this transformation maps the original Tomonaga-Luttinger system on a system of free fermionic quasiparticles. Our representation is useful when the electron dispersion deviates from linear form. For such situation we obtain non-perturbative results for the electron gas free energy and the density-density propagator.

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A. V. Rozhkov. 2005-08-31. Fermionic Quasiparticle Representation of Tomonaga-Luttinger Hamiltonian. https://doi.org/10.1140/epjb%2Fe2005-00312-3

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