We predict that in ${\nu }_T=1\mathrm{}$ bilayer quantum Hall (QH) pseudoferromagnets, an in-plane magnetic field can induce a reentrant pseudospin “canting” transition between interlayer charge balanced (planar) to imbalanced (canted) QH states. At $T=0\mathrm{}$ ( $T>\mathrm{}0\mathrm{}$) this quantum (classical) transition is in a new, anisotropic, compressible $(2+1)\mathrm{D}$ (2D) Ising universality class. The striking experimental signatures are the universal nonlinear charge-voltage and in-plane field relations, and the divergence of the differential bilayer capacitance at the transition, resulting in a bilayer capacitor that spontaneously charges itself, even in the absence of an applied interlayer voltage.

• Received 9 April 2001

DOI:https://doi.org/10.1103/PhysRevLett.87.236802