Abstract: A graphene Hall sensor for operation at cryogenic temperatures is provided. The graphene Hall sensor comprises a substrate, a graphene sheet, a dielectric layer, a first pair of electrical contacts, and a second pair of electrical contacts. The graphene sheet is provided on the substrate. The dielectric layer is provided on the graphene sheet. The graphene sheet and the dielectric layer share a continuous outer edge surface. The first pair of electrical contacts are in electrical contact with the graphene sheet and spaced apart along a first direction. The second pair of electrical contacts are in electrical contact with the graphene sheet and spaced apart along a second direction. The first direction is perpendicular to the second direction, wherein a path along the first direction between the first pair of electrical contacts crosses a path along the second direction between the second pair of electrical contacts. The graphene sheet has a sheet carrier density in the range of 2×1011 cm?2 to 1×1013 cm?2.

Abstract: An information gathering system and method that utilizes a computer to authenticate, poll and store user responses to a customized questionnaire. The questionnaire can be a ballot. The computer utilizes various databases to authenticate and generate the customized questionnaire. The computer records user responses securely and anonymously. User and/or system errors are eliminated before finalizing the response database. An identification number is assigned to each user which allows the user to verify the integrity of the user's response by accessing a response database. The user is provided access to a tabulation database to allow the user to verify the user's voting choices and the voting choices of other voters.