Chiral Surface States in the Bulk Quantum Hall Effect

In layered samples which exhibit a bulk quantum Hall effect (QHE), a two-dimensional (2D) surface ``sheath'' of gapless excitations is expected. These excitations comprise a novel 2D chiral quantum liquid which should dominate the low temperature transport along the field ( z axis). For the integer QHE, we show that localization effects are completely absent in the ``sheath,'' giving a metallic z-axis conductivity. For fractional filling ν0ex0ex=0ex0ex1/3, the sheath is a 2D non-Fermi-liquid, with incoherent z-axis transport and σzz~T³. Experimental implications for the Bechgaard salts are discussed.