Related Experiment Video
Updated: Feb 1, 2026
12:21
Stimulated Stokes and Antistokes Raman Scattering in Microspherical Whispering Gallery Mode Resonators
Published on: April 4, 2016
11.7K
Raman scattering from the bulk inactive out-of-plane mode in few-layer MoTe2
M Grzeszczyk1, K Gołasa1, M R Molas1,2
1Faculty of Physics, University of Warsaw, ul. Pasteura 5, 02-093 Warsaw, Poland.
Scientific Reports
|December 12, 2018
Summary
This study investigates Raman scattering in few-layer molybdenum ditelluride (MoTe2), revealing temperature-dependent double peaks in vibrational modes. This suggests resonant Raman scattering due to electronic band structure interactions.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spectroscopy
Background:
- Few-layer molybdenum ditelluride (MoTe2) exhibits unique vibrational properties.
- Out-of-plane vibrational modes are crucial for understanding MoTe2's lattice dynamics.
Purpose of the Study:
- To investigate high-frequency out-of-plane vibrational modes in few-layer MoTe2.
- To explore the temperature-dependent behavior and resonant characteristics of these modes.
Main Methods:
- Raman scattering spectroscopy was employed.
- Temperature-dependent measurements were conducted.
- Variable excitation laser energies (1.91 eV and 1.96 eV) were used.
Main Results:
- A double peak structure was observed in the Raman spectra of 4- and 5-layer MoTe2 near 291 cm-1.
- The lower and higher energy components of the doublet were attributed to inner and surface layer vibrations, respectively.
- A strong enhancement of the inner mode intensity was observed at low temperatures with specific laser excitations.
Conclusions:
- The observed double peak structure is linked to distinct vibrational contributions from inner and surface layers.
- The intensity enhancement suggests resonant Raman scattering.
- Resonance is proposed to occur with a singularity in the electronic density of states at the M point of the MoTe2 Brillouin zone.
More Related Videos
Related Concept Videos
01:07What is a Mode?
26.0K
The mode is one of the commonly used measures of a central tendency. It is defined as the most frequent value in a data set.
There can be more than one mode in a data set if multiple values have the same highest frequency. For instance, suppose that the Statistics exam scores of 20 students are: 50; 53; 59; 59; 63; 63; 72; 72; 72; 72; 72; 76; 78; 81; 83; 84; 84; 84; 90; 93. Here, the mode is 72, as it occurs most frequently, five times.
A data set with two modes is called bimodal. For example,...
There can be more than one mode in a data set if multiple values have the same highest frequency. For instance, suppose that the Statistics exam scores of 20 students are: 50; 53; 59; 59; 63; 63; 72; 72; 72; 72; 72; 76; 78; 81; 83; 84; 84; 84; 90; 93. Here, the mode is 72, as it occurs most frequently, five times.
A data set with two modes is called bimodal. For example,...
26.0K
01:21Bulk Modulus
763
The bulk modulus is a scientific term used to describe a material's resistance to uniform compression. It is the proportionality constant that links a change in pressure to the resulting relative volume change.
763
01:11Work Done Over an Inclined Plane
4.0K
The center-of-mass framework helps to easily describe the work done on rigid bodies. Since the internal forces in a rigid body do no work, they can be ignored, and the external forces can be considered in the work-energy theorem.
The work done by gravity to move a rigid body, or the work done by an opposing force to move a rigid body against gravity, can be calculated using the center-of-mass framework. It is the line integral of the force of gravity over the path, considered positive if...
The work done by gravity to move a rigid body, or the work done by an opposing force to move a rigid body against gravity, can be calculated using the center-of-mass framework. It is the line integral of the force of gravity over the path, considered positive if...
4.0K
01:14Ventilatory Modes
1.5K
Mechanical ventilators are life-saving devices that support or replace spontaneous breathing. They deliver breaths to patients through varying methods known as ventilator modes. Understanding these modes is critical for healthcare providers managing patients with respiratory failure.
There are three ventilatory modes: full support, partial support, and spontaneous. These are described below.
Full Support Modes
Full support modes include controlled mechanical ventilation, continuous mandatory...
There are three ventilatory modes: full support, partial support, and spontaneous. These are described below.
Full Support Modes
Full support modes include controlled mechanical ventilation, continuous mandatory...
1.5K
01:06Body Planes
31.8K
Body planes in anatomy are imaginary flat surfaces used as reference points to divide the body into sections for anatomical study. These planes are essential for understanding the orientation, relationships, and spatial organization of anatomical structures.
The sagittal plane is the plane that divides the body or an organ vertically into right and left sides. If this vertical plane runs directly down the middle of the body resulting in equal division, it is called the midsagittal or median...
The sagittal plane is the plane that divides the body or an organ vertically into right and left sides. If this vertical plane runs directly down the middle of the body resulting in equal division, it is called the midsagittal or median...
31.8K
01:21Coordinate Plane
347
The Cartesian coordinate plane is a fundamental structure in mathematics that enables the visualization of relationships between numerical values in two dimensions. It is formed by two intersecting number lines: a horizontal x-axis and a vertical y-axis. These axes meet at the origin, the point where both values are zero. Their intersection divides the plane into four quadrants labeled in a counterclockwise direction starting from the upper right.An ordered pair of numbers represents every...
347