15 citations · 43 across the 6 of their papers we have counts for
6 papers
Quantum versus thermal fluctuations in the harmonic chain and experimental implications
K. Schönhammer
The nonzero ground-state energy of the quantum mechanical harmonic oscillator implies quantum fluctuations around the minimum of the potential with the mean square value proportion…
Unusual broadening of wave packets on lattices
K. Schönhammer
The broadening of one-dimensional Gaussian wave packets is presented in all textbooks on quantum mechanics. It is used to elucidate Heisenberg's uncertainty relation. The behaviour…
Deviations from Wick's theorem in the canonical ensemble
K. Schönhammer
Wick's theorem for the expectation values of products of field operators for a system of noninteracting fermions or bosons plays an important role in the perturbative approach to t…
RPAE versus RPA for the Tomonaga model with quadratic energy dispersion
K. Schönhammer
Recently the damping of the collective charge (and spin) modes of interacting fermions in one spatial dimension was studied. It results from the nonlinear correction to the energy…
Luttinger Liquids: The Basic Concepts
K. Schonhammer
This chapter reviews the theoretical description of interacting fermions in one dimension. The Luttinger liquid concept is elucidated using the Tomonaga-Luttinger model as well as…
Canonically conjugate pairs and phase operators
K. Schonhammer
For quantum mechanics on a lattice the position (``particle number'') operator and the quasi-momentum (``phase'') operator obey canonical commutation relations (CCR) only on a dens…