Condensed Matter Seminars

In the superfluid phases of liquid 3He with p-wave spin triplet pairing, all of the continuous symmetry except for the translational symmetry are broken, exhibiting extraordinarily rich physical phenomena. In particular, the surface scattering in unconventional superfluids/superconductors induces quasi-particle sub-gap bound states spatially localized near the surface within the coherence length xo, called the Andreev surface bound states (ASBS). This generic nature of the unconventional order parameter combined with the exotic symmetries in the superfluid phases of 3He lends an unfathomable source of fascinating physical phenomena predicted to exist in confined geometry: crystalline superfluid phase, Majorana fermionic excitations, and helical spin current in the B-phase, and the edge current and the chiral edge state in the A-phase, many of which are of topological origin. We have developed micro-machined probes or micro-electro-mechanical system (MEMS) devices for this purpose. In this talk, we will discuss the design and the operation of the device, and the results obtained using these devices in air, liquid 3He and also in liquid 4He in a wide range of temperature down to submillikelvin range. Our work demonstrates great potential of the device in a wide range of experiments in quantum fluids.