Effects of disorder on transport properties of low-dimensional electronic systems with unconventional band structure

无序对非常规能带结构低维电子系统输运特性的影响

• 批准号: 22540336
• 负责人: KAWARABAYASHI Tohru
• 金额: $ 2.75万
• 依托单位: Toho University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2010
• 资助国家: 日本
• 起止时间: 2010-04-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-22540336/
• 关键词: グラフェン; ディラック電子; ランダウ準位; カイラル対称性; 物性理論; メゾスコピック・局在; メゾス小ピック・局在; メゾスコピック系・局在; 有機導体

Transport properties of two-dimensional massless Dirac fermions, which is realized in graphene and in certain organic metals, in a magnetic field has been investigated both numerically and analytically. We have found that the n=0 Landau level, which is a hallmark of the graphene quantum Hall effect, is surprisingly robust against disorder respecting the chiral symmetry. This robustness appears as a anomalous sharpness of the n=0 Landau level leading to the unconventional criticality of the quantum Hall transition. We have also generalized the chiral symmetry to encompass the generic tilted Dirac fermions and show that the generalized chiral symmetry indeed protects the n=0 Landau level against disorder. These findings suggest that the unconventional quantum Hall transition can be realized in a wide range of systems such as cold atoms in an optical lattice.

通过数值计算和解析方法研究了石墨烯和某些有机金属中二维无质量狄拉克费米子在磁场中的输运性质。我们已经发现，作为石墨烯量子霍尔效应的标志的n=0朗道能级对于关于手性对称性的无序是令人惊讶地稳健的。这种鲁棒性表现为n=0朗道能级的异常尖锐，导致量子霍尔跃迁的非常规临界性。我们还推广了手征对称性，以涵盖一般的倾斜狄拉克费米子，并表明，广义手征对称性确实保护n=0朗道水平对无序。这些结果表明，非常规的量子霍尔跃迁可以在广泛的系统中实现，如冷原子在光学晶格中。

项目成果

Generalization of chiral symmetry for tilted Dirac cones

倾斜狄拉克锥的手性对称性的推广

• DOI: 10.1142/s2010194512006046
• 发表时间: 2012
• 期刊: International Journal of Modern Physics : Conference series
• 作者: Tohru Kawarabayashi;Yasuhiro Hatsugai;Takahiro Morimoto;and Hideo Aoki
• 通讯作者: and Hideo Aoki

Landau levels of disordered massless Dirac fermions when the Dirac cones are both shifted and tilted

当狄拉克锥体移动和倾斜时无序无质量狄拉克费米子的朗道能级

• 发表时间: 2013
• 作者: T. Honda;Y. Hatsugai;H. Aok;T. Kawarabayashi
• 通讯作者: T. Kawarabayashi

ケクレ型ボンド秩序があるグラフェンのドメイン境界における局所状態密度

具有凯库勒型键序的石墨烯域边界处的局部态密度

• 发表时间: 2014
• 作者: 井上裕哉;初貝安弘;青木秀夫;河原林透
• 通讯作者: 河原林透

3層グラフェンのゼロエネルギー・ランダウ準位のランダムネスに対する安定性

三层石墨烯零能朗道能级对抗随机性的稳定性

• 发表时间: 2013
• 作者: 坂本紘樹;初貝安弘;青木秀夫;河原林透
• 通讯作者: 河原林透

Generalization of chiral symmetry for two-dimensional massless fermions with tilted Dirac cones

倾斜狄拉克锥二维无质量费米子手性对称性的推广

• 发表时间: 2011
• 作者: 奥山倫;江藤幹雄;Shigeki Matsunaga;張 紀久夫;T. Kawarabayashi
• 通讯作者: T. Kawarabayashi