Monolithic low-transition-temperature superconducting magnetometers for high resolution imaging magnetic fields of room temperature samples

We have developed a monolithic low-temperature superconducting quantum interference device (SQUID) magnetometer and incorporated the device in a scanning microscope for imaging magnetic fields of room temperature samples. The instrument has a similar to100 mum spatial resolution and a 1.4 pT/Hz(1/2) field sensitivity above a few hertz. We discuss design constraints on and potential applications of the SQUID microscope. (C) 2003 American Institute of Physics.