arXiv subjects

K. Nakada

Publications and source records attributed to K. Nakada.

2 recordsLinked to original sources

arXiv2004

Simultaneous Excitation of Spins and Pseudospins in the Bilayer $ν=1$ Quantum Hall State

The tilting angular dependence of the energy gap was measured in the bilayer quantum Hall state at the Landau level filling $ν=1$ by changing the density imbalance between the two layers. The observed gap behavior shows a continuous transformation from the bilayer balanced density state to the monolayer state. Even a sample with 33 K tunneling gap shows the same activation energy anomaly reported by Murphy {\it et al.}. We discuss a possible relation between our experimental results and the quantum Hall ferromagnet of spins and pseudospins.

cond-mat.mes-hall↗

arXiv2000

The Hypergraphite: A possible extension of graphitic network

We propose a class of networks which can be regarded as an extension of the graphitic network. These networks are constructed so that surface states with non-bonding character (edge states) are formed in a tight-binding model with one orbital for each atomic site. Besides, for several networks, the tight-binding electronic structures become a zero-gap semiconductor. These properties have been found in the $π$-electron system of the graphene. Thus, we call these networks hypergraphite.

cond-mat.mtrl-sci↗