P. Stamp, Assistant Professor

B.Sc., Sussex (1978)
M.Sc., Lancaster (1979)
D.Phil., Sussex (1983)
Postdoct. Appts.: Massachusetts (1983)
Grenoble (1985-87)
Madrid and ITP, Santa Barbara (1988-89)
Royal Society (London), European Fell. (1985-87)
CSIC Personal Investigador, Spain (1988-9)
URF, Vancouver (1989-94)

Research Interests

My main present interests are twofold. First, like many condensed matter theorists, I work on problems involving strongly-interacting fermions. This has previously involved work on 3He (normal, superfluid, and spin-polarized), heavy fermions (normal and superconducting), and high-Tc superconductors. I am now concentrating on interactions which are singular (eg., as ). Apparently pathological, in fact such interactions may be quite common, and lead to a new class of condensed matter systems. Examples of current interest are the 2-d Hubbard model, and the Fractional Hall Effect at finite temperature. I am also interested in exotic superconducting states which can arise in such systems.

Second, I work on a variety of "macroscopic quantum phenomena", where a macroscopic coordinate (or coordinates) must be fully quantized. Of special interest are such phenomena in ferromagnets -- theory predicts that large domain walls (1012 spins) may tunnel through distances 103\AA, at millikelvin temperatures. Theory shows that the coupling to the environment (consisting of magnons, phonons, photons, impurities and defects) does not destroy this tunneling, making this the only serious candidate for macroscopic tunneling apart from SQUIDS.

I am also doing related work on quantum diffusion (of, eg., muons), on the quantum dynamics of vortices in neutron stars, and on dissipative quantum computers and the quantum theory of measurement (the latter being fundamental to macroscopic quantum phenomena). My work on quantum chaotic systems with dissipation is also related to this (and also, amusingly to superstring theory).

Selected Publications

"Effect of singular interaction terms on 2-dimensional Fermi liquids", Phys. Rev. Lett. 68, 2180-2183 (1992), P.C.E. Stamp.

"Quantum Dynamics and Tunneling of Domain Walls in Ferromagnetic Insulators", Phys. Rev. Lett. 66, 2802-2805 (1991), P.C.E. Stamp.

"Quantum Tunneling of Magnetization in Solids", Int. J. Mod. Phys. B6, 1453-1572 (1992), P.C.E. Stamp, E.M. Chudnovsky, B. Barbara.

"Response Functions of a Quantum Fractal System: The Wannier-Azbel-Hofstadter problem", Phys. Rev. Lett. 66, 2503-2506 (1991), P.C.E. Stamp.