Superconductiong magnet for dilutation refrigerator based experiments

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The proposal is a request for funds for a much needed superconducting magnet. My group has developed a strong program in studying properties of novel magnetic materials. In many experiments, we are developing new applications for Superconducting Quantum Interference Devices (SQUIDs), the most sensitive magnet field sensors. This proposed magnet will be abilite to produce a high magnet field around the samples of interest but also provide a shielded low magnetic field region to allow the SQUID electronics to operate. At the moment, we do not have the ability to apply a magnetic field on our dilution refrigerator. With this magnet, we will be able to do many new experiments. For example we will be able to apply the field to the new highly sensitive magneto-caloric sensor that we have developed. This sensor is the most sensitive measurement of this type. It can measure the heat released or absorbed during a low temperature phase transition (similar to melting or freezing of ice), but a thousand times more sensitively than previous measurements. We will use this to detect the smallest levels of heat released from the faintest of phase transitions. This could allow us to detect new phase transitions or with the detection of released heat, put significant constraints on theories to describe the material. A magnet would allow us to extend our studies of phase transitions in materials such as Ho:YLF as a function of magnetic field. We have also developed a high-speed charge detector that should be very effective in studying single spin states of a quantum dot devices for quantum computing applications. To apply this detector to study spin states, a magnet is essential in order to orient the electron spins within the quantum dot.