Related Experiment Video
Updated: Nov 9, 2025
08:53
Angle-resolved Photoemission Spectroscopy At Ultra-low Temperatures
Published on: October 9, 2012
17.9K
Quantum Interference Visibility Spectroscopy in Two-Color Photoemission from Tungsten Needle Tips
Ang Li1, Yiming Pan2, Philip Dienstbier1
1Department of Physics, Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Staudtstraße 1, 91058 Erlangen, Germany.
Physical Review Letters
|April 16, 2021
Summary
Quantum interference in multiphoton photoemission from nanoemitters shows high visibility. This visibility can be tuned from 0% to 100% by adjusting laser intensity ratios, offering new quantum control possibilities.
Area of Science:
- Quantum optics
- Solid-state physics
- Laser-matter interactions
Background:
- Multiphoton excitation involves electrons emitted via various pathways.
- Quantum interference between these pathways causes oscillations in photoemitted electron current.
- Visibility quantifies the strength of this quantum interference.
Purpose of the Study:
- To demonstrate two-color visibility spectroscopy for multiphoton photoemissions.
- To investigate quantum pathway interference visibility across a broad wavelength range.
- To explore the tunability of interference visibility by varying laser intensity ratios.
Main Methods:
- Utilizing two-color femtosecond laser pulses (fundamental ω and second harmonic 2ω).
- Performing spectroscopy on photoemissions from a solid-state nanoemitter.
- Analyzing the visibility of photoemitted electron current oscillations.
Main Results:
- Achieved high photoemission visibility (90% ± 5%) over an octave-spanning wavelength range.
- Observed remarkably constant visibility distribution.
- Demonstrated tunability of visibility from 0% to nearly 100% by adjusting the relative intensity of the two laser colors.
- Validated observations with a simple theoretical model showing excellent quantitative agreement.
Conclusions:
- Two-color visibility spectroscopy is effective for studying multiphoton photoemission.
- Quantum pathway interference in photoemission is highly tunable.
- The findings have broad implications for quantum control in physics, chemistry, and quantum engineering.
Related Concept Videos
01:14UV–Vis Spectrometers
2.1K
The absorbance of UV and visible (UV–visible) radiations is measured using a UV–visible spectrophotometer. Deuterium lamps, which emit UV radiation, and tungsten lamps, which produce radiation in the visible region, are used as light sources in UV–visible spectrophotometers. A monochromator or prism is used for diffraction grating, i.e., to split the incoming radiation into different wavelengths. A system of slits is used to focus the desired wavelength on the sample cell.
2.1K
01:02Ultraviolet and Visible (UV–Vis) Spectroscopy: Overview
3.8K
Ultraviolet–visible (UV–visible or UV–Vis) spectroscopy is an analytical technique that investigates the interaction between matter and UV–Vis light within the electromagnetic spectrum. This method is widely used for its versatility, simplicity, and relatively quick data acquisition, making it valuable for both qualitative and quantitative analysis. When UV–Vis radiation passes through a material, molecules absorb light depending on the energy required for...
3.8K
01:16UV–Vis Spectroscopy: Molecular Electronic Transitions
2.2K
In Ultraviolet–Visible (UV–Vis) spectroscopy, the absorption of electromagnetic radiation is used to probe the electronic structure of molecules. This technique provides insights into molecular electronic transitions, particularly the movement of electrons between different molecular orbitals. Radiation is absorbed if the energy of the electromagnetic radiation passing through the molecule is precisely equal to the energy difference between the excited and ground states. During this...
2.2K
01:30Atomic Emission Spectroscopy: Interference
405
In atomic emission spectroscopy (AES), high-temperature atomizers excite a broad range of elements and molecules that generate complex emissions from sources such as oxides, hydroxides, and flame combustion products in the flame or plasma. Several strategies can be employed to minimize spectral interferences caused by overlapping emission lines or bands. These include increasing instrument resolution, choosing alternative emission lines, optimally placing the detector in low-background regions,...
405
02:26Photoelectric Effect
36.9K
When light of a particular wavelength strikes a metal surface, electrons are emitted. This is called the photoelectric effect. The minimum frequency of light that can cause such emission of electrons is called the threshold frequency, which is specific to the metal. Light with a frequency lower than the threshold frequency, even if it is of high intensity, cannot initiate the emission of electrons. However, when the frequency is higher than the threshold value, the number of electrons ejected...
36.9K
01:29UV–Vis Spectroscopy: Woodward–Fieser Rules
26.9K
UV–Visible absorption spectra of conjugated dienes arise from the lowest energy π → π* transitions. The light-absorbing part of the molecule is called the chromophore, and the substituents directly attached to the chromophore are called auxochromes. A strong correlation exists between the absorption maxima, λmax, and the structure of a conjugated π system. The Woodward–Fieser rules predict the value of λmax for a given structure by adding the...
26.9K