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We report on the fabrication and low-temperature magneto-transport measurements of Hall bar devices with or without antidot arrays made from Bi2Se3topological insulator (TI)thin films[1].The thin films were grown by van De Waals epitaxy on mica substrates [2,3].The TIHall bar devices were fabricated from as-grown thin films (30 nm in thickness)on a mica substrate by photolithography, metal evaporation, lift-off, oxygen plasma etching and focused ion beam milling techniques.The Hall bar devices were studiedat temperatures ranging from 0.1 to 20 K by using a dilution refrigerator ina vectormagnetic field.Here we focus on the results obtained for the devices with antidotarrays.By applyinga perpendicular magnetic field to the thin films(z axis), we obtained both Hall and longitudinalresistancessimultaneously.From the Hall and longitudinalresistances, keyparameters of the films,such as Hall mobility/Vs, sheet carrier density nsheet, mean free path wereestimated at low temperatures.Weak antilocalization (WAL) effectswereobserved clearly, showingpositive magneticresistance with a sharp tip in low magnetic fields (+50 mT).In a highermagnetic field, the magnetoresistances increase linearly with the magnetic field.In addition, we investigated angularmagnetic field dependencesof WAL effects and found out that theeffectsonly responded to the z component of the magnetic field.Therefore, theBi2Se3 thin filmis of atwo-dimensional conductional system.By fitting the WALdata, we extracted phase coherence lengths and factors α which describes the number of two-dimensional channels that contributes to the WAL signals.The phase coherence length increasesexponentially as temperature decreases.Thefactor α is closeto 0.5with little bit negativedeviations.Thisobservation indicatesthat thetwo-dimensional conductive channeldominates the magnetotransport and is consistent with the results obtained by the measurements of the angular magnetic field dependence of WAL effects.Currently, we are working on gatedBi2Se3 thin film devices in which a certainbut not negligibletwo-dimensional bulk conductive channel could be eliminated and unambiguous transport properties of TI surface states can be extracted.