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Register a new userGrand canonical Peierls transition in In/Si(111)
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Authors
Eric Jeckelmann
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Starting from a Su-Schrieffer-Heeger-like model inferred from first-principles simulations, we show that the metal-insulator transition in In/Si(111) is a first-order grand canonical Peierls transition in which the substrate acts as an electron reservoir for the wires. This model explains naturally the existence of a metastable metallic phase over a wide temperature range below the critical temperature and the sensitivity of the transition to doping. Raman scattering experiments corroborate the softening of the two Peierls deformation modes close to the transition.
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We present a generic grand-canonical theory for the Peierls transition in atomic wires deposited on semiconducting substrates such as In/Si(111) using a mean-field solution of the one-dimensional Su-Schrieffer-Heeger model. We show that this simple low-energy effective model for atomic wires can explain naturally the occurrence of a first-order Peierls transition between a uniform metallic phase at high-temperature and a dimerized insulating phase at low temperature as well as the existence of a metastable uniform state below the critical temperature.
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