Hashisaka Masayuki, Ota Tomoaki, Muraki Koji, Fujisawa Toshimasa
Department of Physics, Tokyo Institute of Technology, 2-12-1-H81 Ookayama, Meguro, Tokyo 152-8551, Japan.
NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198, Japan.
Phys Rev Lett. 2015 Feb 6;114(5):056802. doi: 10.1103/PhysRevLett.114.056802. Epub 2015 Feb 3.
We experimentally identify fractional quasiparticle creation in a tunneling process through a local fractional quantum Hall (FQH) state. The local FQH state is prepared in a low-density region near a quantum point contact in an integer quantum Hall (IQH) system. Shot-noise measurements reveal a clear transition from elementary-charge tunneling at low bias to fractional-charge tunneling at high bias. The fractional shot noise is proportional to T(1)(1-T(1)) over a wide range of T(1), where T(1) is the transmission probability of the IQH edge channel. This binomial distribution indicates that fractional quasiparticles emerge from the IQH state to be transmitted through the local FQH state. The study of this tunneling process enables us to elucidate the dynamics of Laughlin quasiparticles in FQH systems.
我们通过一个局域分数量子霍尔(FQH)态的隧穿过程,实验性地识别了分数准粒子的产生。该局域FQH态是在整数量子霍尔(IQH)系统中量子点接触附近的低密度区域制备的。散粒噪声测量揭示了从低偏压下的基本电荷隧穿到高偏压下的分数电荷隧穿的清晰转变。在很宽的T(1)范围内,分数散粒噪声与T(1)(1 - T(1))成正比,其中T(1)是IQH边缘通道的传输概率。这种二项分布表明分数准粒子从IQH态中出现并通过局域FQH态进行传输。对该隧穿过程的研究使我们能够阐明FQH系统中劳克林准粒子的动力学。