industry competitive in the production of NMR/MRI magnets and the associated superconducting wires and cables.

Recommendation: A 40 T all-superconducting magnet should be designed and constructed, building on recent advances in high-temperature superconducting magnet technology.

Finding: The veritable explosion of new materials with new functionalities that we have witnessed in the past decade is a potent driving force for the need to push experimentation to higher fields, where new phases and new behaviors are invariably found. Although pulsed fields will always provide the highest peak fields, many of the most revealing measurement techniques have inherent timescales or sensitivity requirements that make them practical only in constant magnetic fields.

Techniques requiring dc magnetic fields include ultrasensitive voltage measurements that allow high-precision parametric studies of electrical resistance, heat capacity, susceptibility, and thermopower; scanned probe microscopies that provide both atomic-scale imaging and spectroscopic information; and optical spectroscopies performed over a wide range of frequencies. The ability to carry out these measurements, already proven in zero field to provide crucial information, has the potential to open up whole new fields of research and technology. Some examples include the exploration of the normal state that precedes the unconventional superconductivity in the cuprates and iron pnictides and chalcogenides, the manipulation of symmetry-broken phases and unconventional quantum Hall effects in single-layer and few-layer graphene, and the investigation of the interplay between topological insulators and superconductivity. The ability to bring these measurements to new generations of materials and devices in increasingly high magnetic fields would define a world-leading capability and confer a distinct advantage to the researchers who can exploit them.

Recommendation: A 60 T dc hybrid magnet should be designed and built that will capitalize on the success of the current 45 T hybrid magnet at the NHMFL-Tallahassee.

Finding: Many crucial measurements requiring the highest attainable fields can be performed in pulsed magnetic fields with durations on the order of 10 ms. Similar measurements at higher fields than are currently available would allow investigation of phenomena that are now beyond reach.

With the March 2012 attainment of 100 T in a nondestructive 15 ms pulse at



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