Cyclotron resonance in HgTe/CdTe-based heterostructures in high magnetic fields

Area of Science:

• Condensed matter physics
• Semiconductor physics
• Quantum well physics

Background:

• HgTe/CdTe quantum wells exhibit unique electronic properties due to band inversion.
• Understanding these properties is crucial for novel electronic and optoelectronic devices.

Purpose of the Study:

• To investigate the electronic band structure of HgTe/CdTe quantum wells.
• To characterize the behavior of these quantum wells under quantizing magnetic fields.
• To analyze the influence of band structure (inverted vs. normal) on optical properties.

Main Methods:

• Cyclotron resonance spectroscopy was employed.
• Measurements were conducted in quantizing magnetic fields.
• The Kane 8·8 model was used for theoretical interpretation.

Main Results:

• First observation of hole cyclotron resonance in semimetallic HgTe quantum wells with inverted band structure.
• Observation of interband transitions in normal band structure samples, broadened by quantum well width fluctuations.
• Identification of impurity-related magnetoabsorption lines across all sample types.

Conclusions:

• The study provides new insights into the electronic properties of HgTe/CdTe quantum wells.
• Experimental results validate theoretical models like the Kane 8·8 model for these systems.
• The findings contribute to the fundamental understanding and potential applications of topological materials.