Wang Ziqiang
Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467, USA.
Phys Rev Lett. 2004 Apr 2;92(13):136803. doi: 10.1103/PhysRevLett.92.136803.
We study bilayer quantum Hall systems at total Landau level filling factor nu=1 in the presence of interlayer tunneling and coupling to a dissipative normal fluid. Describing the dynamics of the interlayer phase by an effective quantum dissipative XY model, we show that there exists a critical dissipation sigma(c) set by the conductance of the normal fluid. For sigma>sigma(c), interlayer tunnel splitting drives the system to a nu=1 quantum Hall state. For sigma<sigma(c), interlayer tunneling is irrelevant at low temperatures; the system exhibits an excitonic superfluid transition to a collective quantum Hall state supported by spontaneous interlayer phase coherence. The resulting phase structure and the behavior of the in-plane and tunneling currents are studied in connection to experiments.
我们研究了双层量子霍尔系统，其总朗道能级填充因子ν = 1，存在层间隧穿且与耗散正常流体耦合。通过一个有效的量子耗散XY模型描述层间相位的动力学，我们表明存在一个由正常流体电导设定的临界耗散σ(c)。对于σ > σ(c)，层间隧道分裂驱动系统进入ν = 1量子霍尔态。对于σ < σ(c)，层间隧穿在低温下无关紧要；系统表现出激子超流转变，进入由自发层间相位相干支持的集体量子霍尔态。结合实验研究了由此产生的相结构以及面内电流和隧穿电流的行为。
