A new method of preparation of radio-frequency superconducting quantum interference devices on MgB2 thin films is presented. The variable-thickness bridge was prepared by a combination of optical lithography and of the scratching by an atomic force microscope. The critical current of the nanobridge was 0.35 µA at 4.2 K. Non-contact measurements of the current-phase characteristics and of the critical current vs. temperature have been investigated on our structures.

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