Abstract
The Fixed-Phase method, a stochastic approach to deal with complex hermitian Hamiltonians, is reviewed in the context of fermions coupled to external electromagnetic sources. The method uses as a key ingredient a trial phase that plays the role of gauge function in the unitary transformation that maps the original fermion problem to a boson problem for the modulus of the wavefunction. In particular, we investigate the ground state of an ideal 2d electron gas in high magnetic fields at various densities and for filling fractions ν = 1/m. At high electron densities, the Quantum Hall liquid is the stable phase despite the character of particle interactions. Magnetophonon correlations turn out to be essential to explain the transition to an electron Wigner crystal.
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Ortiz, G. (1994). Simulating 2d Fermions in Strong Magnetic Fields. In: Landau, D.P., Mon, K.K., Schüttler, HB. (eds) Computer Simulation Studies in Condensed-Matter Physics VII. Springer Proceedings in Physics, vol 78. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-79293-9_11
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DOI: https://doi.org/10.1007/978-3-642-79293-9_11
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