Tag Archives: science

figure 4 from the paper

New paper: “Metamagnetism and zero-scale-factor universality in the two-dimensional J-Q model”

This week my paper “Metamagnetism and zero-scale-factor universality in the two-dimensional J-Q model” came out in Physical Review B. This paper builds on my previous work studying the 1D J-Q model, focusing on the saturation transition at high magnetic field using quantum Monte Carlo and exact techniques.

Below a critical coupling value (Q/J)min, this saturation transition is continuous, and is an example of “zero-scale-factor” (ZSF) universality. In ZSF, the order parameter (in this case the magnetization) is described by a universal function of the bare coupling constants and no non-universal numbers (Sachdev, 1994). 2D is the upper critical dimension of ZSF, so we expect to see logarithmic violations of the scaling at low temperature. The form of these violations is predicted by Sachdev et al. This paper is the first numerical test of this form, and we find to our surprise that the logarithmic violations do not match the form proposed by Sachdev et al. The reasons for this are currently unclear and merit further investigation.

Above the coupling ratio (Q/J)min, the saturation transition take the form of a sudden magnetization jump an example of metamagnetism, a kind of first-order phase transition. This metamagnetic transition is broadly similar to the one discovered in our previous work on the 1D J-Q model (Iaizzi, 2017). It is caused by the onset of bound states of magnons (spin flips against a polarized background). Using an exact method, we extract the value of (Q/J)min.

This paper is available directly from PRB (paywall); it can also be found on arxiv, or as a free PDF here.

Thanks to my coauthors Kedar Damle and Anders Sandvik.

Book Review: A Guide to Writing for Scientists

Title: A Guide to Writing for Scientists: How to write more easily and effectively throughout your scientific career

cover of book

Author: Stephen B. Heard

Heard has produced an excellent guide to scientific writing that despite its 300 pages, is a pleasure to read. He addresses a huge array of issues that affect scientific writing and manages to do so in a manner that seems to apply well to all scientific writing. Given the gap between Heard’s field and my own, I would say that is a notable accomplishment. In addition to style, peer review, and other issues, Heard offers excellent advice on the process of writing and how one can become a more productive writer.

I highly recommend this book to any scientist. This is a great book to read a little as a time as you sit down to write you next paper. English as an additional language scientists may be especially interested in the chapter on writing in English for non-native speakers.

Find it on: Goodreads, or Amazon