4. The effect of local gating on spin transport. In this section, we discuss the effect of locally applied top gate voltages on the spin transport. In the non-local configuration, a charge current (I) is sent from the injector electrode (2) to the reference electrode (1), and the electrochemical potential difference between the detector electrode (3) and the second reference electrode (4) is measured. The non-local signal (RNL) is given by . The non-local configuration allows for detecting the spin dependent signal and filters the charge related spurious contributions. Figure S4b shows the RT dependence VTG of and at fixed = 0 V. Here, electrode is utilized to locally modulate the charge carriers only in the RNL τS VBG 5 charge current path. The measured from Hanle precession measurements and the extracted seem to very RNL τS weakly depending on the and confirm that spin and charge paths are completely isolated from each other in VTG the non-local geometry. Figure S 4c shows the dependence of non-local resistance at = -30 V and = 0 VTG VBG B T, when the modulation is applied to electrode While electrode significantly modulates the spin signal, 6. 6 electrode does not have any noticeable effect on spin transport. 5 Figure S4: (a) Schematics of the dual-gated, encapsulated device. (b) dependence of and at =0 VTG RNL τS VBG V. The measurement is performed at RT in Sample B, with the modulation applied only to electrode (c) 5. VTG dependence of at = 0 T and = -30 V. The measurement is performed at 2 K. RNL B VBG 5. The effect of annealing on charge transport. Annealing above 300 °C is a standard process to improve the electronic mobility of graphene by removing the fabrication-related residues. Nevertheless, such high temperature annealing degrades the ferromagnetic electrodes. Here, we show the charge transport properties of a partially encapsulated bilayer graphene spin valve device. While the encapsulated regions are protected against the fabrication residues, non-encapsulated region is
4. The effect of local gating on spin transport. In this section, we discuss the effect of locally applied top gate voltages on the spin transport. In the non-local configuration, a charge current (I) is sent from the injector electrode (2) to the reference electrode (1), and the electrochemical potential difference between the detector electrode (3) and the second reference electrode (4) is measured. The non-local signal (RNL) is given by . The non-local configuration allows for detecting the spin dependent signal and filters the charge related spurious contributions. Figure S4b shows the RT VTG dependence of RNL and τS at fixed VBG = 0 V. Here, electrode 5 is utilized to locally modulate the charge carriers only in the charge current path. The measured RNL from Hanle precession measurements and the extracted τS seem to very weakly depending on the VTG and confirm that spin and charge paths are completely isolated from each other in the non-local geometry. Figure S 4c shows the VTG dependence of non-local resistance at VBG = -30 V and B = 0 T, when the modulation is applied to electrode 6. While electrode 6 significantly modulates the spin signal, electrode 5 does not have any noticeable effect on spin transport. Figure S4: (a) Schematics of the dual-gated, encapsulated device. (b) VTG dependence of RNL and τS at VBG =0 V. The measurement is performed at RT in Sample B, with the modulation applied only to electrode 5. (c) VTG dependence of RNL at B = 0 T and VBG = -30 V. The measurement is performed at 2 K. 5. The effect of annealing on charge transport. Annealing above 300 °C is a standard process to improve the electronic mobility of graphene by removing the fabrication-related residues. Nevertheless, such high temperature annealing degrades the ferromagnetic electrodes. Here, we show the charge transport properties of a partially encapsulated bilayer graphene spin valve device. While the encapsulated regions are protected against the fabrication residues, non-encapsulated region is
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