Excitations Near the Boundary Between a Metal and a Mott Insulator

Sherman, A.; Voropajeva, N.

doi:10.1142/s021797921005507x

Cited by 7 publications

(10 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results of Figs. 2 and 3 are rather different from previous work of Sherman et al 25 who found that the antiferromagnetic order can penetrate into the metal to a depth of ten lattice spacings, but are consistent with the shorter-range effects described in Refs. 11 and 12.…”

Section: Magnetic Propertiessupporting

confidence: 60%

Density of states and magnetic correlations at a metal-Mott insulator interface

2012

View full text Add to dashboard Cite

The possibility of novel behavior at interfaces between strongly and weakly correlated materials has come under increased study recently. In this paper, we use determinant quantum Monte Carlo to determine the interpenetration of metallic and Mott-insulator physics across an interface in the two-dimensional Hubbard Hamiltonian. We quantify the behavior of the density of states at the Fermi level and the short-and long-range antiferromagnetism as functions of the distance from the interface and with different interaction strength, temperature, and hopping across the interface. Induced metallic behavior into the insulator is evident over several lattice spacings, whereas antiferromagnetic correlations remain small on the metallic side. At large interface hopping, singlets form between the two boundary layers, shielding the two systems from each other.

show abstract

Section: Magnetic Propertiessupporting

confidence: 60%

Density of states and magnetic correlations at a metal-Mott insulator interface

2012

View full text Add to dashboard Cite

show abstract

“…The dominant feature of the coupling of the metal and strongly interacting material is a suppression of magnetic order on the correlated side. We did not observe the converse phenomenon, namely a significant penetration of magnetism into the metal, as has been noted in [10]. It is possible this difference arises from the lower value of the on-site interaction, U/t = 4, used here, compared to U/t ≈ 17 in [10].…”

supporting

confidence: 47%

“…We did not observe the converse phenomenon, namely a significant penetration of magnetism into the metal, as has been noted in [10]. It is possible this difference arises from the lower value of the on-site interaction, U/t = 4, used here, compared to U/t ≈ 17 in [10]. Such large couplings are difficult to treat in DQMC.…”

supporting

confidence: 41%

Kondo Screening and Magnetism at Interfaces

et al. 2012

View full text Add to dashboard Cite

The nature of magnetic order and transport properties near surfaces is a topic of great current interest. Here we model metal-insulator interfaces with a multilayer system governed by a tight-binding Hamiltonian in which the interaction is nonzero on one set of adjacent planes and zero on another. As the interface hybridization is tuned, magnetic and metallic properties undergo an evolution that reflects the competition between antiferromagnetism and (Kondo) singlet formation in a scenario similar to that occurring in heavy-fermion materials. For a few-layer system at intermediate hybridization, a Kondo insulating phase results, where magnetic order and conductivity are suppressed in all layers. As more insulating layers are added, magnetic order is restored in all correlated layers except that at the interface. Residual signs of Kondo physics are however evident in the bulk as a substantial reduction of the order parameter in the 2 to 3 layers immediately adjacent to the interfacial one. We find no signature of long-range magnetic order in the metallic layers.

show abstract

“…For J 3 = 0 the problem reduces to two noninteracting semi-infinite antiferromagnets, which spin excitations were considered in Refs. [7,[9][10][11]. As mentioned in the Introduction, the spectrum of each antiferromagnet consists of a quasi-2D mode of spin waves, which are mainly located in two nearboundary layers, and bulk modes of standing spin waves in the rest of the crystal.…”

Section: Spin Excitationsmentioning

confidence: 99%

“…Spin excitations and correlations near this interface were investigated in Refs. [6][7][8][9][10][11]. In particular, it was shown that the antiferromagnet is divided into two regions with different spin excitations [9][10][11].…”

Section: Introductionmentioning

confidence: 99%

Excitations and spin correlations near the interface of two three-dimensional Heisenberg antiferromagnets

Voropajeva

Sherman

2012

Physics Letters A

Self Cite

View full text Add to dashboard Cite

Magnetic excitations and spin correlations near the interface of two spin-1 2 Heisenberg antiferromagnets are considered using the spin-wave approximation. When the interaction between boundary spins differs essentially from exchange constants inside the antiferromagnets, quasi-two-dimensional spin waves appear in the near-boundary region. They eject bulk magnons from this region, thereby dividing the antiferromagnets into areas with different magnetic excitations. The decreased dimensionality of the near-boundary modes leads to amplified nearest-neighbor spin correlations in the interface area.

show abstract

Excitations Near the Boundary Between a Metal and a Mott Insulator

Cited by 7 publications

References 15 publications

Density of states and magnetic correlations at a metal-Mott insulator interface

Density of states and magnetic correlations at a metal-Mott insulator interface

Kondo Screening and Magnetism at Interfaces

Excitations and spin correlations near the interface of two three-dimensional Heisenberg antiferromagnets

Contact Info

Product

Resources

About