Superconductiong magnet for dilutation refrigerator based experiments

该提案是为急需的超导磁体申请资金。我的小组在研究新型磁性材料的特性方面制定了一个强有力的计划。在许多实验中，我们正在开发超导量子干涉器件（squid）的新应用，这是最敏感的磁场传感器。这种提议的磁铁将能够在感兴趣的样品周围产生高磁场，但也提供一个屏蔽的低磁场区域，以允许SQUID电子设备运行。目前，我们还没有能力在稀释冰箱上施加磁场。有了这块磁铁，我们就能做许多新的实验。例如，我们将能够将该领域应用于我们开发的新型高灵敏度磁热传感器。这种传感器是这类测量中最灵敏的。它可以测量低温相变（类似于冰的融化或冻结）过程中释放或吸收的热量，但灵敏度比以前的测量高一千倍。我们将用它来探测从最微弱的相变中释放的最小热量。这可以让我们检测到新的相变，或者通过检测释放的热量，对描述材料的理论施加重大限制。磁铁将允许我们扩展我们的研究相变的材料，如Ho:YLF作为磁场的函数。我们还开发了一种高速电荷探测器，它应该非常有效地研究量子点器件的单自旋态，用于量子计算应用。要应用这个探测器来研究自旋态，磁体是必不可少的，以确定量子点内电子自旋的方向。

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.