Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Tunable metal-insulator transition in double-layer graphene heterostructures
AU - Ponomarenko, L. A.
AU - Geim, A. K.
AU - Zhukov, A. A.
AU - Jalil, R.
AU - Morozov, S. V.
AU - Novoselov, K. S.
AU - Grigorieva, I. V.
AU - Hill, E. H.
AU - Cheianov, V. V.
AU - Falko, V.
AU - Watanabe, K.
AU - Taniguchi, T.
AU - Gorbachev, R. V.
PY - 2011/10/9
Y1 - 2011/10/9
N2 - Disordered conductors with resistivity above the resistance quantum h/e(2) should exhibit an insulating behaviour at low temperatures, a universal phenomenon known as a strong (Anderson) localization(1-3). Observed in a multitude of materials, including damaged graphene and its disordered chemical derivatives(4-10), Anderson localization has not been seen in generic graphene, despite its resistivity near the neutrality point reaching approximate to h/e(2) per carrier type(4,5). It has remained a puzzle why graphene is such an exception. Here we report a strong localization and the corresponding metal-insulator transition in ultra-high-quality graphene. The transition is controlled externally, by changing the carrier density in another graphene layer placed at a distance of several nm and decoupled electrically. The entire behaviour is explained by electron-hole puddles that disallow localization in standard devices but can be screened out in double-layer graphene. The localization that occurs with decreasing rather than increasing disorder is a unique occurrence, and the reported double-layer heterostructures presents a new experimental system that invites further studies.
AB - Disordered conductors with resistivity above the resistance quantum h/e(2) should exhibit an insulating behaviour at low temperatures, a universal phenomenon known as a strong (Anderson) localization(1-3). Observed in a multitude of materials, including damaged graphene and its disordered chemical derivatives(4-10), Anderson localization has not been seen in generic graphene, despite its resistivity near the neutrality point reaching approximate to h/e(2) per carrier type(4,5). It has remained a puzzle why graphene is such an exception. Here we report a strong localization and the corresponding metal-insulator transition in ultra-high-quality graphene. The transition is controlled externally, by changing the carrier density in another graphene layer placed at a distance of several nm and decoupled electrically. The entire behaviour is explained by electron-hole puddles that disallow localization in standard devices but can be screened out in double-layer graphene. The localization that occurs with decreasing rather than increasing disorder is a unique occurrence, and the reported double-layer heterostructures presents a new experimental system that invites further studies.
KW - Electronics, photonics and device physics
KW - Condensed-matter physics
KW - Nanotechnology
UR - http://www.scopus.com/inward/record.url?scp=80053537848&partnerID=8YFLogxK
U2 - 10.1038/nphys2114
DO - 10.1038/nphys2114
M3 - Journal article
VL - 7
SP - 958
EP - 961
JO - Nature Physics
JF - Nature Physics
SN - 1745-2473
IS - 12
ER -