# Magnetoconductivity and Terahertz Response of a HgCdTe Epitaxial Layer

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## Abstract

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## 1. Introduction

## 2. Materials and Methods

#### The Sample and Experimental Procedures

## 3. Results

#### 3.1. Tensor of Magnetoconductivity and Mobility of Carriers in the Epitaxial Layer

#### 3.2. THz Spectroscopy of the Epitaxial Layer

## 4. Discussion

#### 4.1. Magnetoconductivity

#### 4.2. THz Spectroscopy

## 5. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## Appendix A

**Figure A1.**(

**a**) Input data to test the numerical procedure of the mobility spectrum calculations. (

**b**–

**d**) Mobility spectrum calculated for different parameters N, $\delta B$ and ${B}_{max}$, as described in the text.

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**Figure 1.**Evolution of bands in Hg${}_{1-x}$Cd${}_{x}$Te mixed crystals as a function of Cadmium content, x.

**Figure 2.**A content of Cadmium in the epitaxial layer studied as a function of the distance from the sample’s surface (at d = 0).

**Figure 3.**A voltage drop ${U}_{12}$ between two adjacent contacts (1 and 2) registered at the current of 1 $\mathsf{\mu}$A supplied to the other pair of contacts (3 and 4). The horizontal scale shows the current flowing through the superconducting coil expressed as a coil magnetic field with the coil constant of 6.393 A/T.

**Figure 4.**Components of the conductivity tensor at 120 K (

**left**) and 2 K (

**right**). Points: experimental results; smooth solid lines—fits of Equation (1) with N = 1. Note a different range of B in the two panels.

**Figure 5.**Evolution of the mobility spectrum as a function of temperature. Negative mobility corresponds to electrons, positive mobility to holes. The right panel shows an enlarged zero-centered part of the left panel. The spectra are shifted vertically for better presentation. Downward triangles mark results of fit of Equation (1) with N = 1.

**Figure 7.**Transmission of 2.54 THz radiation in an experimental configuration with a circular polarizer.

**Figure 8.**

**Left**: photocurrent (normalized to the value at B = 0) measured at monochromatic excitation with radiation of frequency indicated in the right panel;

**Right**: photoconductivity (normalized to the value at B = 0) at indicated frequencies. The curves in both panels are shifted vertically for better presentation.

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**MDPI and ACS Style**

Yavorskiy, D.; Karpierz, K.; Baj, M.; Bąk, M.M.; Mikhailov, N.N.; Dvoretsky, S.A.; Gavrilenko, V.I.; Knap, W.; Teppe, F.; Łusakowski, J. Magnetoconductivity and Terahertz Response of a HgCdTe Epitaxial Layer. *Sensors* **2018**, *18*, 4341.
https://doi.org/10.3390/s18124341

**AMA Style**

Yavorskiy D, Karpierz K, Baj M, Bąk MM, Mikhailov NN, Dvoretsky SA, Gavrilenko VI, Knap W, Teppe F, Łusakowski J. Magnetoconductivity and Terahertz Response of a HgCdTe Epitaxial Layer. *Sensors*. 2018; 18(12):4341.
https://doi.org/10.3390/s18124341

**Chicago/Turabian Style**

Yavorskiy, Dmitriy, Krzysztof Karpierz, Michał Baj, Małgorzata M. Bąk, Nikolai N. Mikhailov, Sergey A. Dvoretsky, Vladimir I. Gavrilenko, Wojciech Knap, Frederic Teppe, and Jerzy Łusakowski. 2018. "Magnetoconductivity and Terahertz Response of a HgCdTe Epitaxial Layer" *Sensors* 18, no. 12: 4341.
https://doi.org/10.3390/s18124341