TY - JOUR AU - Zhang, A. AU - Chen, T. AU - Song, S. AU - Yang, W. AU - Justin, Gooding J. AU - Liu, J. TI - Ultrafast generation of highly crystalline graphene quantum dots from graphite paper via laser writing JF - JOURNAL OF COLLOID AND INTERFACE SCIENCE J2 - J COLLOID INTERF SCI VL - 594 PY - 2021 SP - 460 EP - 465 PG - 6 SN - 0021-9797 DO - 10.1016/j.jcis.2021.03.044 UR - https://m2.mtmt.hu/api/publication/32013091 ID - 32013091 LA - English DB - MTMT ER - TY - JOUR AU - Kiran, H. C. AU - Gangadharappa, H. V. TI - Reinforcing nanomedicine using graphene nanoribbons JF - JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY J2 - J DRUG DELIV SCI TEC VL - 49 PY - 2019 SP - 334 EP - 344 PG - 11 SN - 1773-2247 DO - 10.1016/j.jddst.2018.12.004 UR - https://m2.mtmt.hu/api/publication/30545355 ID - 30545355 LA - English DB - MTMT ER - TY - JOUR AU - Zhang, Guan-Qun AU - Lin, Li AU - Peng, Hailin AU - Liu, Zhongfan AU - Kang, Ning AU - Xu, Hong-Qi TI - Coulomb-dominated oscillations in a graphene quantum Hall Fabry-Perot interferometer JF - CHINESE PHYSICS B J2 - CHINESE PHYS B VL - 28 PY - 2019 IS - 12 PG - 5 SN - 1674-1056 DO - 10.1088/1674-1056/ab55d3 UR - https://m2.mtmt.hu/api/publication/31391116 ID - 31391116 AB - The electronic Fabry-Perot interferometer operating in the quantum Hall regime may be a promising tool for probing edge state interferences and studying the non-Abelian statistics of fractionally charged quasiparticles. Here we report on realizing a quantum Hall Fabry-Perot interferometer based on monolayer graphene. We observe resistance oscillations as a function of perpendicular magnetic field and gate voltage both on the electron and hole sides. Their Coulomb-dominated origin is revealed by the positive (negative) slope of the constant phase lines in the plane of magnetic field and gate voltage on the electron (hole) side. Our work demonstrates that the graphene interferometer is feasible and paves the way for the studies of edge state interferences since high-Landau-level and even denominator fractional quantum Hall states have been found in graphene. LA - English DB - MTMT ER - TY - JOUR AU - Makk, Péter AU - Handschin, Clevin AU - Tóvári, Endre AU - Watanabe, Kenji AU - Taniguchi, Takashi AU - Richter, Klaus AU - Liu, Ming-Hao AU - Schönenberger, Christian TI - Coexistence of classical snake states and Aharanov-Bohm oscillations along graphene pn junctions JF - PHYSICAL REVIEW B J2 - PHYS REV B VL - 98 PY - 2018 IS - 3 PG - 36 SN - 2469-9950 DO - 10.1103/PhysRevB.98.035413 UR - https://m2.mtmt.hu/api/publication/3411145 ID - 3411145 LA - English DB - MTMT ER - TY - JOUR AU - Overweg, Hiske AU - Rickhaus, Peter AU - Eich, Marius AU - Lee, Yongjin AU - Pisoni, Riccardo AU - Watanabe, Kenji AU - Taniguchi, Takashi AU - Ihn, Thomas AU - Ensslin, Klaus TI - Edge channel confinement in a bilayer graphene n-p-n quantum dot JF - NEW JOURNAL OF PHYSICS J2 - NEW J PHYS VL - 20 PY - 2018 PG - 6 SN - 1367-2630 DO - 10.1088/1367-2630/aa9cd3 UR - https://m2.mtmt.hu/api/publication/27343215 ID - 27343215 LA - English DB - MTMT ER - TY - JOUR AU - Mirzakhani, M AU - Zarenia, M AU - Vasilopoulos, P AU - Peeters, F M TI - Electrostatically confined trilayer graphene quantum dots JF - PHYSICAL REVIEW B J2 - PHYS REV B VL - 95 PY - 2017 IS - 15 PG - 9 SN - 2469-9950 DO - 10.1103/PhysRevB.95.155434 UR - https://m2.mtmt.hu/api/publication/26766823 ID - 26766823 LA - English DB - MTMT ER - TY - JOUR AU - Morgenstern, M AU - Freitag, N AU - Nent, A AU - Nemes Incze, Péter AU - Liebmann, M TI - Graphene Quantum Dots Probed by Scanning Tunneling Microscopy JF - ANNALEN DER PHYSIK J2 - ANN PHYS-BERLIN VL - 529 PY - 2017 IS - 11 PG - 9 SN - 0003-3804 DO - 10.1002/andp.201700018 UR - https://m2.mtmt.hu/api/publication/3311748 ID - 3311748 AB - Scanning tunneling spectroscopy results probing the electronic properties of graphene quantum dots are reviewed. After a short summary of the study of squared wave functions of graphene quantum dots on metal substrates, we firstly present data where the Landau level gaps caused by a perpendicular magnetic field are used to electrostatically confine electrons in monolayer graphene, which are probed by the Coulomb staircase revealing the consecutive charging of a quantum dot. It turns out that these quantum dots exhibit much more regular charging sequences than lithographically confined ones. Namely, the consistent grouping of charging peaks into quadruplets, both, in the electron and hole branch, portrays a regular orbital splitting of about 10meV. At low hole occupation numbers, the charging peaks are, partly, additionally grouped into doublets. The spatially varying energy separation of the doublets indicates a modulation of the valley splitting by the underlying BN substrate. We outline that this property might be used to eventually tune the valley splitting coherently. Afterwards, we describe graphene quantum dots with multiple contacts produced without lithographic resist, namely by local anodic oxidation. Such quantum dots target the goal to probe magnetotransport properties during the imaging of the corresponding wave functions by scanning tunneling spectroscopy. LA - English DB - MTMT ER - TY - JOUR AU - Overweg, Hiske AU - Eggimann, Hannah AU - Liu, Ming-Hao AU - Varlet, Anastasia AU - Eich, Marius AU - Simonet, Pauline AU - Lee, Yongjin AU - Watanabe, Kenji AU - Taniguchi, Takashi AU - Richter, Klaus AU - Fal'ko, Vladimir I AU - Ensslin, Klaus AU - Ihn, Thomas TI - Oscillating Magnetoresistance in Graphene p-n Junctions at Intermediate Magnetic Fields JF - NANO LETTERS J2 - NANO LETT VL - 17 PY - 2017 IS - 5 SP - 2852 EP - 2857 PG - 6 SN - 1530-6984 DO - 10.1021/acs.nanolett.6b05318 UR - https://m2.mtmt.hu/api/publication/26765259 ID - 26765259 LA - English DB - MTMT ER - TY - JOUR AU - Cohnitz, L AU - De Martino, A AU - Hausler, W AU - Egger, R TI - Chiral interface states in graphene p-n junctions JF - PHYSICAL REVIEW B J2 - PHYS REV B VL - 94 PY - 2016 IS - 16 PG - 11 SN - 2469-9950 DO - 10.1103/PhysRevB.94.165443 UR - https://m2.mtmt.hu/api/publication/26408895 ID - 26408895 LA - English DB - MTMT ER - TY - JOUR AU - Freitag, NM AU - Chizhova, LA AU - Nemes Incze, Péter AU - Woods, CR AU - Gorbachev, RV AU - Cao, Yixin AU - Geim, AK AU - Novoselov, KS AU - Burgdörfer, Joachim AU - Libisch, F AU - Morgenstern, M TI - Electrostatically Confined Monolayer Graphene Quantum Dots with Orbital and Valley Splittings JF - NANO LETTERS J2 - NANO LETT VL - 16 PY - 2016 IS - 9 SP - 5798 EP - 5805 PG - 8 SN - 1530-6984 DO - 10.1021/acs.nanolett.6b02548 UR - https://m2.mtmt.hu/api/publication/3162462 ID - 3162462 AB - The electrostatic confinement of massless charge carriers is hampered by Klein tunneling. Circumventing this problem in graphene mainly relies on carving out nanostructures or applying electric displacement fields to open a band gap in bilayer graphene. So far, these approaches suffer from edge disorder or insufficiently controlled localization of electrons. Here we realize an alternative strategy in monolayer graphene, by combining a homogeneous magnetic field and electrostatic confinement. Using the tip of a scanning tunneling microscope, we induce a confining potential in the Landau gaps of bulk graphene without the need for physical edges. Gating the localized states toward the Fermi energy leads to regular charging sequences with more than 40 Coulomb peaks exhibiting typical addition energies of 7-20 meV. Orbital splittings of 4-10 meV and a valley splitting of about 3 meV for the first orbital state can be deduced. These experimental observations are quantitatively reproduced by tight binding calculations, which include the interactions of the graphene with the aligned hexagonal boron nitride substrate. The demonstrated confinement approach appears suitable to create quantum dots with well-defined wave function properties beyond the reach of traditional techniques. LA - English DB - MTMT ER -