Regensburg 2025 – wissenschaftliches Programm
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HL: Fachverband Halbleiterphysik
HL 31: Focus Session: Young Semiconductor Forum Poster
HL 31.6: Poster
Mittwoch, 19. März 2025, 12:15–13:00, H13
Resistance standards from artifact wire coils to graphene quantum Hall resistance — •Yefei Yin1, Mattias Kruskopf1, Stephan Bauer1, Teresa Tschirner1, Klaus Pierz1, Frank Hohls1, Rolf J. Haug2, and Hans W. Schumacher1 — 1Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany — 2Institut für Festkörperphysik, Leibniz Universität Hannover, 30167 Hannover, Germany
Historically, resistance standards were made by physical artifact wire coils before 1990 and quantum resistors based on GaAs heterostructures after 1990. However, conventional GaAs quantum Hall resistance (QHR) standards with the quantized resistance RH = h/2e2 are operating under high magnetic flux densities B > 10 T, limited currents I < 50 µA, and low temperatures T < 1.5 K, which significantly hinder the dissemination of primary resistance standards. In this work, we developed practical primary QHR standards based on n- and p-type epitaxial graphene. This study first systematically demonstrated that p-type epitaxial graphene can also be used for primary resistance standards, as accurate (10−9 accuracy) as GaAs and n-type graphene counterparts for realizing the SI unit ohm in quantum metrology. [1] The n-type graphene QHR standards achieved the world best performance so far with a 10−9 accuracy under relaxed conditions (B = 4.5 T, I = 232.5 µA, T = 4.2 K) simultaneously. [2-3] Our graphene QHR standards have been utilized in the national metrology institutes in European countries. [1] Appl. Phys. Lett., 125, 064001 (2024). [2] Adv. Phys. Res. 1, 2200015 (2022). [3] Phys. Rev. Applied, 2024
Keywords: quantum Hall effect; quantum Hall resistance standard; epitaxial graphene; quantum metrology