Rounding by disorder of first-order quantum phase transitions: emergence of quantum critical points

Pallab Goswami; David Schwab; Sudip Chakravarty

doi:10.1103/physrevlett.100.015703

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arXiv · 0708.2917

Rounding by disorder of first-order quantum phase transitions: emergence of quantum critical points

Pallab Goswami·David Schwab·Sudip Chakravarty

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Abstract

We give a heuristic argument for disorder rounding of a first order quantum phase transition into a continuous phase transition. From both weak and strong disorder analysis of the the N-color quantum Ashkin-Teller model in one spatial dimension, we find that for $N \geq 3$, the first order transition is rounded to a continuous transition and the physical picture is the same as the random transverse field Ising model for a limited parameter regime. The results are strikingly different from the corresponding classical problem in two dimensions where the fate of the renormalization group flows is a fixed point corresponding to N-decoupled pure Ising models.

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Pallab Goswami, David Schwab, Sudip Chakravarty. 2008-01-08. Rounding by disorder of first-order quantum phase transitions: emergence of quantum critical points. https://doi.org/10.1103/physrevlett.100.015703

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