Magnetic STM with a non-magnetic tip

• Main Authors: RUF; RALPH, GAMBINO; RICHARD J, ZELDOV; ELIA
• Format: Patent
• Language: English
• Published: 19.07.1994
• Edition: 5
• Subjects: APPLICATIONS OF SCANNING-PROBE TECHNIQUES, e.g. SCANNING PROBEMICROSCOPY [SPM]; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PHYSICS; SCANNING-PROBE TECHNIQUES OR APPARATUS; STATIC STORES; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ARTCOLLECTIONS [XRACs] AND DIGESTS; TESTING

An apparatus and method for imaging the magnetic structure and the magnetic domains of a sample is described incorporating a scanning tunneling microscope (STM), a voltage generator for varying the voltage on the tip, an ammeter for measuring the current through the tip, circuitry to determine the tip voltage at zero current and a current source for passing current longitudinally through the sample. The invention may further include an applied magnetic field in the plane of the sample and orthogonal to current passing through the sample. A high density non-volatile memory is described incorporating the above apparatus except for the applied magnetic field and further incorporating a layer of ferromagnetic material having magnetic domains therein indicative of information.