| AVS 65th International Symposium & Exhibition | |
| 2D Materials Focus Topic | Thursday Sessions |
| Session 2D-ThP |
| Session: | 2D Materials Poster Session |
| Presenter: | Johannes Schwenk, National Institute of Standards and Technology (NIST)/ University of Maryland, College Park |
| Authors: | J. Schwenk, National Institute of Standards and Technology (NIST)/ University of Maryland, College Park S. Kim, National Institute of Standards and Technology (NIST) / Department of Physics and Astronomy, Seoul National University, Seoul, Korea F. Ghahari, National Institute of Standards and Technology (NIST)/ University of Maryland, College Park J. Berwanger, Institut für Experimentelle und Angewandte Physik, Universität Regensburg, Germany W.G. Cullen, National Institute of Standards and Technology (NIST) S.R. Blankenship, National Institute of Standards and Technology (NIST) Y. Kuk, Department of Physics and Astronomy, Seoul National University, Seoul, Korea F.J. Giessibl, Institut für Experimentelle und Angewandte Physik, Universität Regensburg, Germany N.B. Zhitenev, National Institute of Standards and Technology (NIST) J.A. Stroscio, National Institute of Standards and Technology (NIST) |
| Correspondent: | Click to Email |
We present initial studies of a backgated graphene Hall bar device using simultaneous measurements of atomic force microscopy (AFM), scanning tunneling microscopy (STM) and electronic transport. Laterally resolved spectroscopy with high energy resolution is used for the investigation of exotic ground states and edge channels within the two-dimensional graphene electron system, which enables us to explore links between the local microscopic behavior of the device and its mesoscopic transport properties.
A recently constructed microscope uses a self-sensing quartz sensor (qPlus) and operates in an ultra-high vacuum (UHV) environment inside a dilution refrigerator (DR) with a base temperature of 10 ͏mK and magnetic fields up to 15 ͏T ͏[1]. Radio frequency (RF) filtering of all signal lines entering the UHV chamber and improved home built RF powder filters at the 10 ͏mK stage were implemented to produce an improved energy resolution in tunneling spectroscopy. Low noise preamplifiers for the sensor deflection ͏[2] and the STM current signal ͏[3] were implemented at the 4 ͏K stage within the DR. This allows for reduced Johnson noise of the amplifier feedback resistors and a relatively short distance (1.2 ͏m) between amplifier and the STM/AFM module where the sensor is operating. In this poster we describe aspects of the instrumentation and initial measurements of the graphene Hall bar device.
[1] Song et al., Review of Scientific Instruments 81, 121101 (2010); doi: 10.1063/1.3520482
[2] Huber and Giessibl, Review of Scientific Instruments 88, 073702 (2017); doi: 10.1063/1.4993737
[3] adapted from le Sueur and Joyez, Review of Scientific Instruments 77, 123701 (2006); doi: 10.1063/1.2400024