1,070 research outputs found
Self-resonant Coil for Contactless Electrical Conductivity Measurement under Pulsed Ultra-high Magnetic Fields
In this study, we develop experimental apparatus for contactless electrical
conductivity measurements under pulsed high magnetic fields over 100 T using a
self-resonant-type high-frequency circuit. The resonant power spectra were
numerically analyzed, and the conducted simulations showed that the apparatus
is optimal for electrical conductivity measurements of materials with high
electrical conductivity. The newly developed instruments were applied to a
high-temperature cuprate superconductor LaSrCuO to show
conductivity changes in magnetic fields up to 102 T with a good signal-to-noise
ratio. The upper critical field was determined with high accuracy.Comment: 11 pages, 5 figure
Form factors and action of U_{\sqrt{-1}}(sl_2~) on infinite-cycles
Let be a sequence of
skew-symmetric polynomials in satisfying , whose coefficients are symmetric Laurent polynomials in . We
call an -cycle if
holds for all .
These objects arise in integral representations for form factors of massive
integrable field theory, i.e., the SU(2)-invariant Thirring model and the
sine-Gordon model. The variables are the integration
variables and are the rapidity variables. To each
-cycle there corresponds a form factor of the above models.
Conjecturally all form-factors are obtained from the -cycles.
In this paper, we define an action of
on the space of -cycles.
There are two sectors of -cycles depending on whether is even or
odd. Using this action, we show that the character of the space of even (resp.
odd) -cycles which are polynomials in is equal to the
level irreducible character of with lowest
weight (resp. ). We also suggest a possible tensor
product structure of the full space of -cycles.Comment: 27 pages, abstract and section 3.1 revise
Algebraic representation of correlation functions in integrable spin chains
Taking the XXZ chain as the main example, we give a review of an algebraic
representation of correlation functions in integrable spin chains obtained
recently. We rewrite the previous formulas in a form which works equally well
for the physically interesting homogeneous chains. We discuss also the case of
quantum group invariant operators and generalization to the XYZ chain.Comment: 31 pages, no figur
- β¦