Lifetime reduction of surface states at Cu, Ag, and Au(111) caused by impurity scattering

Heers, Swantje; Mavropoulos, Phivos; Lounis, Samir; Zeller, R.; Blügel, Stefan

doi:10.1103/physrevb.86.125444

Cited by 12 publications

(19 citation statements)

References 46 publications

(68 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The importance of resonant scattering in metals is well known, including trivial surface states as e.g. the (111) surface states of the noble metals 25,27 . Here we have seen that the TSS are just as susceptible to resonant scattering, with the difference that the scattering is mostly forward-directed and exact or near backscattering is absent or strongly suppressed, respectively.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Lifetime and surface-to-bulk scattering off vacancies of the topological surface state in the three-dimensional strong topological insulators Bi2Te3 and Bi2Se3

Rüßmann

Mavropoulos

Blügel

2019

Journal of Physics and Chemistry of Solids

Self Cite

View full text Add to dashboard Cite

We analyze the finite lifetimes of the topologically protected electrons in the surface state of Bi 2 Te 3 and Bi 2 Se 3 due to elastic scattering off surface vacancies and as a function of energy. The scattering rates are decomposed into surface-to-surface and surface-to-bulk contributions, giving us new fundamental insights into the scattering properties of the topological surface states (TSS). If the number of possible final bulk states is much larger than the number of final surface states, then the surface-to-bulk contribution is of importance, otherwise the surface-to-surface contribution dominates. Additionally, we find defect resonances that have a significant impact on the scattering properties of the TSS. They can strongly change the lifetime of the surface state to vary between tens of fs to ps at surface defect concentrations of 1 at%.

show abstract

Section: Discussionmentioning

confidence: 99%

“…The perturbed potential and density were also calculated within the LDA. The T -matrix and scattering rates were calculated in the KKR representation as described elsewhere 24,25 . Structural relaxations around the vacancy can be important in the calculation of the vacancy-formation energy.…”

Section: Introductionmentioning

confidence: 99%

Lifetime and surface-to-bulk scattering off vacancies of the topological surface state in the three-dimensional strong topological insulators Bi2Te3 and Bi2Se3

Rüßmann

Mavropoulos

Blügel

2019

Journal of Physics and Chemistry of Solids

Self Cite

View full text Add to dashboard Cite

show abstract

“…From the latter, the scattering probability and the momentum-as well as the spin-flip relaxation rate can be quantitatively determined via the spin-dependent scattering matrix. [20][21][22][23][24] Knowledge of the spin-dependent scattering probability allows us to employ the Boltzmann equation for spin Hall transport. 12,36,37 Then, the spin Hall conductivity as well as the spin Hall angle are calculated.…”

Section: Theorymentioning

confidence: 99%

“…[18][19][20][21][22][23][24][25] However, little is known about these effects in metallic thin films with thickness in the nanometer regime. Owing to the breaking of translational symmetry in thin films, many parameters have to be taken into account, such as the thickness and the crystalline orientation of the films.…”

Section: Introductionmentioning

confidence: 99%

Spin relaxation and spin Hall transport in5dtransition-metal ultrathin films

et al. 2014

Self Cite

View full text Add to dashboard Cite

The spin relaxation induced by the Elliott-Yafet mechanism and the extrinsic spin Hall conductivity due to the skew-scattering are investigated in 5d transition-metal ultrathin films with self-adatom impurities as scatterers. The values of the Elliott-Yafet parameter and of the spin-flip relaxation rate reveal a correlation with each other that is in agreement with the Elliott approximation. At 10-layer thickness, the spin-flip relaxation time in 5d transition-metal films is quantitatively reported about few hundred nanoseconds at atomic percent which is one and two orders of magnitude shorter than that in Au and Cu thin films, respectively. The anisotropy effect of the Elliott-Yafet parameter and of the spin-flip relaxation rate with respect to the direction of the spin-quantization axis in relation to the crystallographic axes is also analyzed. We find that the anisotropy of the spin-flip relaxation rate is enhanced due to the Rashba surface states on the Fermi surface, reaching values as high as 97% in 10-layer Hf(0001) film or 71% in 10-layer W(110) film. Finally, the spin Hall conductivity as well as the spin Hall angle due to the skew-scattering off self-adatom impurities are calculated using the Boltzmann approach. Our calculations employ a relativistic version of the first-principles full-potential Korringa-Kohn-Rostoker Green function method.

show abstract

“…The quasistationary surface state resonances or image potential resonances (IPRs) are then formed. The total decay rate =h/τ (τ being the lifetime) of an electronic excitation in the quasistationary IPR state is thus determined by four contributions: 26,31 inelastic electron-electron scattering 4,5 (decay rate ee ), electron-phonon interaction 32,33 ( ep ), electron-defect scattering 34 ( ed ), and energy-conserving resonant one-electron tunneling into the bulk [35][36][37][38] ( 1e ). The one-electron transfer into the substrate is thought to be faster than the many-body decay and so to dominate the population decay of the quasistationary states at low defect surfaces.…”

Section: Introductionmentioning

confidence: 99%

Green's function approach to the lifetimes of image potential resonances at metal surfaces

2013

View full text Add to dashboard Cite

We present a theoretical study of the image potential resonances (IPRs) at metal surfaces. We develop the Green's functions approach allowing us to calculate binding energies E n and lifetimes τ n of IPRs with high quantum numbers n (up to 10 in this work). A systematic study is performed at the point for the close-packed metal surfaces: Cu(111), Ag(111), Au(111), Al(001), Al(111), Be(0001), Mg(0001), Na(110), Li (110), and also at the Y point on Cu(110). The calculated lifetimes of IPRs on close-packed surfaces demonstrate the scaling law τ n ∝ n 3 . Our results are in agreement with available experimental data. We show that at the Y point on Cu(110) each quantum number n corresponds to a pair of IPRs n + and n − , where the energy difference E n+ − E n− is proportional to n −3 . The lifetimes τ n+ and τ n− differ significantly, however, they both obey the scaling law τ n± ∝ n 3 . Since the electrons trapped in the long-lived IPRs are strongly localized on the vacuum side, we argue that the inelastic electron-electron and electron-phonon scattering have a small contribution to the decay rate of these IPRs. The latter is dominated by the resonant electron transfer into the bulk.

show abstract

Lifetime reduction of surface states at Cu, Ag, and Au(111) caused by impurity scattering

Cited by 12 publications

References 46 publications

Lifetime and surface-to-bulk scattering off vacancies of the topological surface state in the three-dimensional strong topological insulators Bi2Te3 and Bi2Se3

Lifetime and surface-to-bulk scattering off vacancies of the topological surface state in the three-dimensional strong topological insulators Bi2Te3 and Bi2Se3

Spin relaxation and spin Hall transport in5dtransition-metal ultrathin films

Green's function approach to the lifetimes of image potential resonances at metal surfaces

Contact Info

Product

Resources

About