Two Length Scales and Crossover Behavior in the Critical Diffuse Scattering from <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>V</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow><mi>H</mi></math></span>

J. Trenkler; P. C. Chow; P. Wochner; H. Abe; K. E. Bassler; R. Paniago; H. Reichert; D. Scarfe; T. H. Metzger; J. Peisl; J. Bai; S. C. Moss

doi:10.1103/PhysRevLett.81.2276

Two Length Scales and Crossover Behavior in the Critical Diffuse Scattering from $V_{2} H$

J. Trenkler, P. C. Chow, P. Wochner, H. Abe, K. E. Bassler, R. Paniago, H. Reichert, D. Scarfe, T. H. Metzger, J. Peisl, J. Bai, and S. C. Moss

Phys. Rev. Lett. 81, 2276 – Published 14 September 1998

Abstract

We have observed two length scales in a $V_{2} H$ crystal above the $β_{1} - β_{2}$ phase transition. A sharp Lorentzian profile in the critical diffuse scattering was superimposed on a broader one for a low-energy x-ray experiment in reflection, while no sharp component appeared in transmission at high energy. For the sharp component, we extracted tricritical exponents $ν_{1}$ and $γ_{1}$ at small reduced temperatures $t$ , where fluctuations are coherent over large distances. For larger $t$ , where the correlation length is comparable to an effective defect size, there is a crossover to altered exponents.

Received 3 June 1998

DOI:https://doi.org/10.1103/PhysRevLett.81.2276

Authors & Affiliations

J. Trenkler¹, P. C. Chow¹, P. Wochner^2,*, H. Abe¹, K. E. Bassler¹, R. Paniago^1,†, H. Reichert^1,‡, D. Scarfe¹, T. H. Metzger³, J. Peisl³, J. Bai⁴, and S. C. Moss¹

¹Department of Physics, University of Houston, Houston, Texas 77204-5506
²Department of Physics, Brookhaven National Laboratory, Upton, New York 11973
³Sektion Physik, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, 80539 München, Germany
⁴Oak Ridge Associated Universities, Oak Ridge, Tennessee 37831

^*Present address: Max-Planck-Institut für Metallforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
^†Present address: Departamento de Fisica, UFMG, Belo Horizonte, CEP 30123-970, Brazil.
^‡