Final-state band structure-induced modulations of the photoemission linewidth in angle-resolved valence band spectra: a case study on Bi(1 1 1)

Attosecond spectroscopic techniques have made it possible to measure differences in transport times for photoelectrons from localized core levels and delocalized valence bands in solids. We report the application of attosecond pulse trains to directly and unambiguously measure the difference in lifetimes between photoelectrons born into free electron–like states and those excited into unoccupied excited states in the band structure of nickel (111). An enormous increase in lifetime of 212 ± 30 attoseconds occurs when the final state coincides with a short-lived excited state. Moreover, a strong dependence of this lifetime on emission angle is directly related to the final-state band dispersion as a function of electron transverse momentum. This finding underscores the importance of the material band structure in determining photoelectron lifetimes and corresponding electron escape depths.

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Phase identification in binary mixture of nanopowders from deconvoluted valence band spectra using X-ray photoelectron spectroscopy: Case study with iron oxide and titania polymorphs

Applied Surface Science ◽

10.1016/j.apsusc.2018.08.132 ◽

2018 ◽

Vol 462 ◽

pp. 932-943 ◽

Cited By ~ 3

Author(s):

D. Nanda Gopala Krishna ◽

C. Anushree ◽

R.P. George ◽

John Philip

Keyword(s):

Iron Oxide ◽

Binary Mixture ◽

Valence Band ◽

Photoelectron Spectroscopy ◽

Phase Identification ◽

X Ray ◽

Band Spectra

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Valence-band structure ofα−MoTe2by angular-resolved photoelectron spectroscopy in the constant-final-state mode

Physical Review B ◽

10.1103/physrevb.60.4675 ◽

1999 ◽

Vol 60 (7) ◽

pp. 4675-4681 ◽

Cited By ~ 15

Author(s):

Th. Böker ◽

A. Müller ◽

J. Augustin ◽

C. Janowitz ◽

R. Manzke

Keyword(s):

Band Structure ◽

Valence Band ◽

Photoelectron Spectroscopy ◽

Final State ◽

Valence Band Structure

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Attosecond intra-valence band dynamics and resonant-photoemission delays in W(110)

Nature Communications ◽

10.1038/s41467-021-23650-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

S. Heinrich ◽

T. Saule ◽

M. Högner ◽

Y. Cui ◽

V. S. Yakovlev ◽

...

Keyword(s):

Valence Band ◽

Photoelectron Spectroscopy ◽

Electronic Band Structure ◽

Photoelectric Effect ◽

Final State ◽

Electronic Band ◽

Time Resolved ◽

Resonant Photoemission ◽

Pulse Trains ◽

Electron Correlation Effects

AbstractTime-resolved photoelectron spectroscopy with attosecond precision provides new insights into the photoelectric effect and gives information about the timing of photoemission from different electronic states within the electronic band structure of solids. Electron transport, scattering phenomena and electron-electron correlation effects can be observed on attosecond time scales by timing photoemission from valence band states against that from core states. However, accessing intraband effects was so far particularly challenging due to the simultaneous requirements on energy, momentum and time resolution. Here we report on an experiment utilizing intracavity generated attosecond pulse trains to meet these demands at high flux and high photon energies to measure intraband delays between sp- and d-band states in the valence band photoemission from tungsten and investigate final-state effects in resonant photoemission.

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The Highly Uniform Photoresponsivity from Visible to Near IR Light in Sb2Te3 Flakes

Sensors ◽

10.3390/s21041535 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1535

Author(s):

Shiu-Ming Huang ◽

Jai-Lung Hung ◽

Mitch Chou ◽

Chi-Yang Chen ◽

Fang-Chen Liu ◽

...

Keyword(s):

Band Structure ◽

Energy Difference ◽

Experimental Result ◽

Light Illumination ◽

Near Ir ◽

State Band ◽

Valence Bands ◽

Low Dimensional ◽

Low Dimensional Materials ◽

Ir Light

Broadband photosensors have been widely studied in various kinds of materials. Experimental results have revealed strong wavelength-dependent photoresponses in all previous reports. This limits the potential application of broadband photosensors. Therefore, finding a wavelength-insensitive photosensor is imperative in this application. Photocurrent measurements were performed in Sb2Te3 flakes at various wavelengths ranging from visible to near IR light. The measured photocurrent change was insensitive to wavelengths from 300 to 1000 nm. The observed wavelength response deviation was lower than that in all previous reports. Our results show that the corresponding energies of these photocurrent peaks are consistent with the energy difference of the density of state peaks between conduction and valence bands. This suggests that the observed photocurrent originates from these band structure peak transitions under light illumination. Contrary to the most common explanation that observed broadband photocurrent carrier is mainly from the surface state in low-dimensional materials, our experimental result suggests that bulk state band structure is the main source of the observed photocurrent and dominates the broadband photocurrent.

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