Semiconducting YBCO device and superconducting YBCO device locally converted by AFM tip and manufacturing methods therefor

A method of manufacturing a semiconducting yttrium-barium-copper-oxygen (YBCO) device locally converted by an atomic force microscope (AFM), the method comprising the steps of:

• depositing a semiconducting YBCO film over a MgO substrate;
• forming electrodes at the ends of the semiconducting YBCO film;
• and
• placing an AFM tip on the semiconducting YBCO film between the electrodes and applying a predetermined voltage between the AFM tip and the electrodes to convert a local region of the semiconducting YBCO film contacted by the AFM tip to a nonconducting YBCO so that a tunnel junction may be formed in the local region of the semiconducting YBCO film.

A superconducting yttrium-barium-copper-oxygen (YBCO) device locally converted by an atomic force microscope (AFM), the device comprising:

• a MgO substrate;
• a superconducting YBCO film stacked on the MgO substrate;
• a nonsuperconducting YBCO region locally converted so as to form a tunnel junction in the superconducting YBCO film;
• and
• electrodes formed at the ends of the superconducting YBCO film.

A method of manufacturing a superconducting yttrium-barium-copper-oxygen (YBCO) device locally converted by an atomic force microscope (AFM), the method comprising the steps of:

• depositing a superconducting YBCO film over a MgO substrate;
• forming electrodes at the ends of the superconducting YBCO film;
• and
• placing an AFM tip on the superconducting YBCO film between the electrodes and applying a predetermined voltage between the AFM tip and the electrodes to convert a local region of the superconducting YBCO film contacted by the AFM tip to a nonsuperconducting YBCO so that a tunnel junction may be formed in the local region of the superconducting YBCO film.