EXPERIMENTS IN PULSED MAGNETIC-FIELDS AT AT-AND-T-BELL-LABORATORIES

We review a pair of experiments performed in the pulsed magnets at AT& T Bell Laboratories. Resonant tunneling experiments directly measure t he two-dimensional (2-D) density of states of a quantum well, includin g a series of energy level anti-crossings due to magnetopolaron format ion. These experiments also study the degenerate 2-D emitter, directly measuring chemical potential jumps at both integer and fractional Lan dau level fillings. Pulsed field studies of the Kondo insulator Ce3Bi4 Pt3 establish that a correlated insulating ground state forms at low t emperatures. Magnetic fields of approximately 50 T suppress the Kondo interaction and the associated collective energy gap.