A clamp and a method for installing the clamp into at least two work pieces is provided. In the central portion of a silicon substrate 1, a recess portion 2 is formed which includes a beam structure. Specifically, the size to be defined by subtracting a thickness of the light blocking film at the side wall from a width of the engraved portion is made equal to 1. The resistive element further comprises a control terminal allowing adjustment of the variable resistance. A cover member is openably secured over the open upper end of the narrow upper duct portion of the housing. The invention uses a novel geometry to overcome limitations of other design, and allows full exploitation of existing superconducting materials.