TY - JOUR

T1 - Electronic phase transitions in quasi-one-dimensional atomic chains

T2 - Au wires on Si(553)

AU - Yogi, Priyanka

AU - Koch, Julian

AU - Sanna, Simone

AU - Pfnür, Herbert

N1 - Funding Information: We gratefully acknowledge the financial support by the Deutsche Forschungsgemeinschaft (research unit FOR1700, Projects No. SA 1948/1-2 and No. TE 386/10-2). The calculations presented in this work were conducted on the Lichtenberg high-performance computer of the TU Darmstadt, and at the Höchstleistungrechenzentrum Stuttgart (HLRS). The authors furthermore acknowledge the computational resources provided by the HPC Core Facility and the HRZ of the Justus-Liebig-Universität Gießen and assistance by Zamin Mamyiev in Au coverage calibration.

PY - 2022/6/7

Y1 - 2022/6/7

N2 - The Si(553) surface, covered with half a monolayer of gold, forms a double strand of well-ordered atomic Au chains in each miniterrace. It represents one of the smallest possible realizations of quasi-one-dimensional (1D) systems. In this prototype system, by combining DC conductance and low-energy electron diffraction measurements with density functional calculations and ab initio Monte Carlo simulations, we demonstrate that nonlocal electronic correlations, together with thermal excitations, lead to peculiar phase transitions without long-range order. They are characterized by marginal (average) geometric relaxations, but with huge variations of the electronic band structure and concomitant strong temperature-dependent modifications of the density of states close to the Fermi level. Similar phenomena are expected in the large class of quasi-1D conductors and open a wide range of possibilities for their controlled manipulation. It is the increasing hybridization between spin-polarized Au and Si edge states that makes the Si dangling bond states at the step edge conducting, first as a transient between two insulating phases and finally opening a permanent new 1D conduction channel at high temperatures.

AB - The Si(553) surface, covered with half a monolayer of gold, forms a double strand of well-ordered atomic Au chains in each miniterrace. It represents one of the smallest possible realizations of quasi-one-dimensional (1D) systems. In this prototype system, by combining DC conductance and low-energy electron diffraction measurements with density functional calculations and ab initio Monte Carlo simulations, we demonstrate that nonlocal electronic correlations, together with thermal excitations, lead to peculiar phase transitions without long-range order. They are characterized by marginal (average) geometric relaxations, but with huge variations of the electronic band structure and concomitant strong temperature-dependent modifications of the density of states close to the Fermi level. Similar phenomena are expected in the large class of quasi-1D conductors and open a wide range of possibilities for their controlled manipulation. It is the increasing hybridization between spin-polarized Au and Si edge states that makes the Si dangling bond states at the step edge conducting, first as a transient between two insulating phases and finally opening a permanent new 1D conduction channel at high temperatures.

UR - http://www.scopus.com/inward/record.url?scp=85132335938&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.105.235407

DO - 10.1103/PhysRevB.105.235407

M3 - Article

AN - SCOPUS:85132335938

VL - 105

JO - Physical Review B

JF - Physical Review B

SN - 2469-9950

IS - 23

M1 - 235407

ER -