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arXiv · 1307.0519

Fate of CP(N-1) fixed points with q-monopoles

Matthew S. Block·Roger G. Melko·Ribhu K. Kaul
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Abstract

We present an extensive quantum Monte Carlo study of the N\'eel-valence bond solid (VBS) phase transition on rectangular and honeycomb lattice SU($N$) antiferromagnets in sign problem free models. We find that in contrast to the honeycomb lattice and previously studied square lattice systems, on the rectangular lattice for small $N$ a first order N\'eel-VBS transition is realized. On increasing $N\geq 4$, we observe that the transition becomes continuous and with the {\em same} universal exponents as found on the honeycomb and square lattices (studied here for $N=5,7,10$), providing strong support for a deconfined quantum critical point. Combining our new results with previous numerical and analytical studies we present a general phase diagram of the stability of $\mathbb{CP}^{N-1}$ fixed points with $q$-monopoles.

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Matthew S. Block, Roger G. Melko, Ribhu K. Kaul. 2013-07-01. Fate of CP(N-1) fixed points with q-monopoles. https://doi.org/10.1103/physrevlett.111.137202

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