Gauge Fluctuations and Interlayer Coherence in Bilayer Composite Fermion Metals

Abstract

We study the effect of the Chern-Simons gauge fields on the possible transition from two decoupled composite fermion metals to the interlayer coherent composite fermion state proposed by Alicea et al. [Phys. Rev. Lett. 103, 256403 (2009)] in a symmetrically doped quantum Hall bilayer with total Landau level filling fraction ${\nu }_{tot}=1$. In this transition, interlayer Coulomb repulsion leads to excitonic condensation of composite fermions which are then free to tunnel coherently between layers. We find that this coherent tunneling is strongly suppressed by the layer-dependent Aharonov-Bohm phases experienced by composite fermions as they propagate through the fluctuating gauge fields in the system. This suppression is analyzed by treating these gauge fluctuations within the random-phase approximation and calculating their contribution to the energy cost for forming an exciton condensate of composite fermions. This energy cost leads to (1) an increase in the critical interlayer repulsion needed to drive the transition; and (2) a discontinuous jump in the energy gaps to out-of-phase excitations (i.e., excitations involving currents with opposite signs in the two layers) at the transition.

13 pages, 9 figures

References in corpus (4)

• Paired composite fermion phase of quantum Hall bilayers at ν= 1/2 + 1/2
• Trial Wavefunctions for ν= 1/2 + 1/2 Quantum Hall Bilayers
• Intrinsic gap and exciton condensation in the nu_T=1 bilayer system
• The Kohn-Luttinger Effect in Gauge Theories

Cited by in corpus (15)

• Luttinger theorem for the strongly correlated Fermi liquid of composite fermions
• Pairing in half-filled Landau level
• Precursors to Exciton Condensation in Quantum Hall Bilayers
• Numerical Study of Quantum Hall Bilayers at Total Filling ${\nu }_T=1$: A New Phase at Intermediate Layer Distances
• $s$-wave paired composite-fermion electron-hole trial state for quantum Hall bilayers with $\nu =1$
• Interlayer Pairing Symmetry of Composite Fermions in Quantum Hall Bilayers
• Wave Function and Emergent SU(2) Symmetry in ${\nu }_T=1$ Quantum Hall Bilayer
• Paired states in half-filled Landau levels
• Pairing of Composite-Electrons and Composite-Holes in ${\nu }_T=1$ Quantum Hall Bilayers
• Exciton Condensation in Quantum Hall Bilayers at Total Filling ${\nu }_T=5$
• Quantum Hall bilayer in dipole representation
• Successive electron-vortex binding in quantum Hall bilayers at $\nu =\frac{1}{4}+\frac{3}{4}$
• Single-parameter variational wavefunctions for quantum Hall bilayers
• On dualities of paired quantum Hall bilayer states at ${\nu }_T=\frac{1}{2}+\frac{1}{2}$
• Role of the compensating current in the weak Josphson coupling regime: An extended study on excitonic Josephson junctions