A ug 2 00 1 Phase transition and spin - wave dispersion in quantum Hall bilayers at filling factor ν = 1
نویسندگان
چکیده
We present an effective Hamiltonian for a bilayer quantum Hall system at filling factor ν = 1 neglecting charge fluctuations. Our model is formulated in terms of spin and pseudospin operators and is an exact representation of the system within the above approximation. We analyze its low-lying excitations in terms of spin-wave theory. Moreover we add to previous first-principle exact-diagonalization studies concentrating on the quantum phase transition seen in this system. 73.43-f,7321-b Typeset using REVTEX e-mail: [email protected] 1
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1 M ay 2 00 1 Phase transition and spin - wave dispersion in quantum Hall bilayers at filling factor ν = 1
We present an effective Hamiltonian for a bilayer quantum Hall system at filling factor ν = 1 neglecting charge fluctuations. Our model is formulated in terms of spin and pseudospin operators and is an exact representation of the system within the above approximation. We analyze its lowlying excitations in terms os spin wave theory. Moreover we add to previous exact diagonalization studies of t...
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