Single layer graphene Hall sensors for scanning Hall probe microscopy (SHPM) in 3–300K temperature range

Abstract

• Graphene Hall probes (GHPs) were fabricated for a scanning Hall probe microscope (SHPM). • Minimum detectable magnetic field of GHPs was found to be comparable with conventional Hall probe materials. • The magnetic domains in NdFeB demagnetized magnet were successfully observed at 300 K, 126 K and 3 K for the first time by using GHP. Graphene micro-Hall probes were developed for a scanning Hall probe microscope system and used for the direct magnetic imaging domains of demagnetized NdFeB permanent magnet for the first time. The Hall coefficient and minimum magnetic field resolution of graphene Hall probes at 1 kHz were found to be 0.18 Ω/G and 0.20 G / Hz for a drive current of 3 μA at room temperature in vacuum. The magnetic domains in NdFeB demagnetized magnet were observed at 300 K, 126 K and 3 K successfully.