Integer and fractional quantum Hall effects in bilayer electron systems |
| |
| Institution: | 1. Department of Physics, Tohoku University, Sendai 980-8578, Japan;2. Institute of Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan;1. Department of Physics, Harbin Institute of Technology, Harbin 150001, China;2. Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China;3. International Quantum Academy, Shenzhen 518048, China;4. Guangdong Provincial Key Laboratory of Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China;5. Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China |
| |
| Abstract: | Integer and fractional quantum Hall (QH) effects are studied in bilayer electron systems both theoretically and experimentally, especially, at ν=2 and 2/3. Due to the spin and layer degrees of freedom, the SU(4) symmetry underlies the integer QH states, where quantum coherence develops spontaneously and quasiparticles are coherent excitations. It is intriguing that a pair of skyrmions makes one quasiparticle at ν=2. In the fractional QH regime, on the other hand, the composite-fermion cyclotron gap competes with the Zeeman and tunneling gaps, bringing in new phases and excitations. At ν=2/3 our experimental data suggest that a quasiparticle is not a coherent excitation but simply a composite fermion. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
