TY  - JOUR
AU  - Atić, Aleksandar
AU  - Wang, Xizhe
AU  - Vuković, Nikola
AU  - Stanojević, Novak
AU  - Demić, Aleksandar
AU  - Indjin, Dragan
AU  - Radovanović, Jelena
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12868
AB  - ZnO-based heterostructures are up-and-coming candidates for terahertz (THz) optoelectronic devices, largely owing to their innate material attributes. The significant ZnO LO-phonon energy plays a pivotal role in mitigating thermally induced LO-phonon scattering, potentially significantly elevating the temperature performance of quantum cascade lasers (QCLs). In this work, we calculate the electronic structure and absorption of ZnO/ZnMgO multiple semiconductor quantum wells (MQWs) and the current density–voltage characteristics of nonpolar m-plane ZnO/ZnMgO double-barrier resonant tunnelling diodes (RTDs). Both MQWs and RTDs are considered here as two building blocks of a QCL. We show how the doping, Mg percentage and layer thickness affect the absorption of MQWs at room temperature. We confirm that in the high doping concentrations regime, a full quantum treatment that includes the depolarisation shift effect must be considered, as it shifts mid-infrared absorption peak energy for several tens of meV. Furthermore, we also focus on the performance of RTDs for various parameter changes and conclude that, to maximise the peak-to-valley ratio (PVR), the optimal doping density of the analysed ZnO/Zn88Mg12O double-barrier RTD should be approximately 1018 cm−3, whilst the optimal barrier thickness should be 1.3 nm, with a Mg mole fraction of ~9%.
T2  - Materials
T1  - Resonant Tunnelling and Intersubband Optical Properties of ZnO/ZnMgO Semiconductor Heterostructures: Impact of Doping and Layer Structure Variation
VL  - 17
IS  - 4
SP  - 927
DO  - 10.3390/ma17040927
ER  - 

@article{
author = "Atić, Aleksandar and Wang, Xizhe and Vuković, Nikola and Stanojević, Novak and Demić, Aleksandar and Indjin, Dragan and Radovanović, Jelena",
year = "2024",
abstract = "ZnO-based heterostructures are up-and-coming candidates for terahertz (THz) optoelectronic devices, largely owing to their innate material attributes. The significant ZnO LO-phonon energy plays a pivotal role in mitigating thermally induced LO-phonon scattering, potentially significantly elevating the temperature performance of quantum cascade lasers (QCLs). In this work, we calculate the electronic structure and absorption of ZnO/ZnMgO multiple semiconductor quantum wells (MQWs) and the current density–voltage characteristics of nonpolar m-plane ZnO/ZnMgO double-barrier resonant tunnelling diodes (RTDs). Both MQWs and RTDs are considered here as two building blocks of a QCL. We show how the doping, Mg percentage and layer thickness affect the absorption of MQWs at room temperature. We confirm that in the high doping concentrations regime, a full quantum treatment that includes the depolarisation shift effect must be considered, as it shifts mid-infrared absorption peak energy for several tens of meV. Furthermore, we also focus on the performance of RTDs for various parameter changes and conclude that, to maximise the peak-to-valley ratio (PVR), the optimal doping density of the analysed ZnO/Zn88Mg12O double-barrier RTD should be approximately 1018 cm−3, whilst the optimal barrier thickness should be 1.3 nm, with a Mg mole fraction of ~9%.",
journal = "Materials",
title = "Resonant Tunnelling and Intersubband Optical Properties of ZnO/ZnMgO Semiconductor Heterostructures: Impact of Doping and Layer Structure Variation",
volume = "17",
number = "4",
pages = "927",
doi = "10.3390/ma17040927"
}

Atić, A., Wang, X., Vuković, N., Stanojević, N., Demić, A., Indjin, D.,& Radovanović, J.. (2024). Resonant Tunnelling and Intersubband Optical Properties of ZnO/ZnMgO Semiconductor Heterostructures: Impact of Doping and Layer Structure Variation. in Materials, 17(4), 927.
https://doi.org/10.3390/ma17040927

Atić A, Wang X, Vuković N, Stanojević N, Demić A, Indjin D, Radovanović J. Resonant Tunnelling and Intersubband Optical Properties of ZnO/ZnMgO Semiconductor Heterostructures: Impact of Doping and Layer Structure Variation. in Materials. 2024;17(4):927.
doi:10.3390/ma17040927 .

Atić, Aleksandar, Wang, Xizhe, Vuković, Nikola, Stanojević, Novak, Demić, Aleksandar, Indjin, Dragan, Radovanović, Jelena, "Resonant Tunnelling and Intersubband Optical Properties of ZnO/ZnMgO Semiconductor Heterostructures: Impact of Doping and Layer Structure Variation" in Materials, 17, no. 4 (2024):927,
https://doi.org/10.3390/ma17040927 . .

TY  - JOUR
AU  - Radovanović, Jelena V.
AU  - Pereira, Mauro F.
AU  - Indjin, Dragan
AU  - Sumetsky, Mikhail
AU  - Stepić, Milutin
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1203
T2  - Optical and Quantum Electronics
T1  - Advances in the science of light
VL  - 48
IS  - 8
DO  - 10.1007/s11082-016-0651-6
ER  - 

@article{
author = "Radovanović, Jelena V. and Pereira, Mauro F. and Indjin, Dragan and Sumetsky, Mikhail and Stepić, Milutin",
year = "2016",
journal = "Optical and Quantum Electronics",
title = "Advances in the science of light",
volume = "48",
number = "8",
doi = "10.1007/s11082-016-0651-6"
}

Radovanović, J. V., Pereira, M. F., Indjin, D., Sumetsky, M.,& Stepić, M.. (2016). Advances in the science of light. in Optical and Quantum Electronics, 48(8).
https://doi.org/10.1007/s11082-016-0651-6

Radovanović JV, Pereira MF, Indjin D, Sumetsky M, Stepić M. Advances in the science of light. in Optical and Quantum Electronics. 2016;48(8).
doi:10.1007/s11082-016-0651-6 .

Radovanović, Jelena V., Pereira, Mauro F., Indjin, Dragan, Sumetsky, Mikhail, Stepić, Milutin, "Advances in the science of light" in Optical and Quantum Electronics, 48, no. 8 (2016),
https://doi.org/10.1007/s11082-016-0651-6 . .

TY  - JOUR
AU  - Vuković, Nikola
AU  - Daničić, Aleksandar
AU  - Radovanović, Jelena V.
AU  - Milanović, Vitomir B.
AU  - Indjin, Dragan
PY  - 2015
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/471
AB  - One of the challenges in the design of metamaterials unit cells is the reduction of losses caused by the metallic inclusions. In order to overcome this obstacle, it has been proposed to use the active medium as the unit cell. Quantum cascade lasers are great candidates for the active medium materials since they are able to provide high values of optical gain. In this paper we investigate and compare two quantum cascade structures optimized for emission frequencies lower than 2 THz and simulate the effect of a strong magnetic field applied perpendicularly to the layers. Comprehensive description of conduction-band nonparabolicity is used to calculate the electronic structure, and subsequently evaluate the longitudinal optical phonon and interface roughness scattering rates and solve the system of rate equations which govern the distribution of carriers among the Landau levels. Once we assess the degree of population inversion, we have all the necessary information about the permittivity component along the growth direction of the structure and may determine the conditions under which the structure displays negative refraction.
T2  - Optical and Quantum Electronics
T1  - Possibilities of achieving negative refraction in QCL-based semiconductor metamaterials in the THz spectral range
VL  - 47
IS  - 4
SP  - 883
EP  - 891
DO  - 10.1007/s11082-014-0020-2
ER  - 

@article{
author = "Vuković, Nikola and Daničić, Aleksandar and Radovanović, Jelena V. and Milanović, Vitomir B. and Indjin, Dragan",
year = "2015",
abstract = "One of the challenges in the design of metamaterials unit cells is the reduction of losses caused by the metallic inclusions. In order to overcome this obstacle, it has been proposed to use the active medium as the unit cell. Quantum cascade lasers are great candidates for the active medium materials since they are able to provide high values of optical gain. In this paper we investigate and compare two quantum cascade structures optimized for emission frequencies lower than 2 THz and simulate the effect of a strong magnetic field applied perpendicularly to the layers. Comprehensive description of conduction-band nonparabolicity is used to calculate the electronic structure, and subsequently evaluate the longitudinal optical phonon and interface roughness scattering rates and solve the system of rate equations which govern the distribution of carriers among the Landau levels. Once we assess the degree of population inversion, we have all the necessary information about the permittivity component along the growth direction of the structure and may determine the conditions under which the structure displays negative refraction.",
journal = "Optical and Quantum Electronics",
title = "Possibilities of achieving negative refraction in QCL-based semiconductor metamaterials in the THz spectral range",
volume = "47",
number = "4",
pages = "883-891",
doi = "10.1007/s11082-014-0020-2"
}

Vuković, N., Daničić, A., Radovanović, J. V., Milanović, V. B.,& Indjin, D.. (2015). Possibilities of achieving negative refraction in QCL-based semiconductor metamaterials in the THz spectral range. in Optical and Quantum Electronics, 47(4), 883-891.
https://doi.org/10.1007/s11082-014-0020-2

Vuković N, Daničić A, Radovanović JV, Milanović VB, Indjin D. Possibilities of achieving negative refraction in QCL-based semiconductor metamaterials in the THz spectral range. in Optical and Quantum Electronics. 2015;47(4):883-891.
doi:10.1007/s11082-014-0020-2 .

Vuković, Nikola, Daničić, Aleksandar, Radovanović, Jelena V., Milanović, Vitomir B., Indjin, Dragan, "Possibilities of achieving negative refraction in QCL-based semiconductor metamaterials in the THz spectral range" in Optical and Quantum Electronics, 47, no. 4 (2015):883-891,
https://doi.org/10.1007/s11082-014-0020-2 . .

TY  - JOUR
AU  - Erich, Marko
AU  - Radovanović, Jelena V.
AU  - Milanović, Vitomir B.
AU  - Ikonić, Zoran
AU  - Indjin, Dragan
PY  - 2008
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/3437
AB  - We have analyzed the influence of Dresselhaus and Rashba spin-orbit couplings (caused by the bulk inversion asymmetry and the structural asymmetry, respectively) on electron tunneling through a double- and triple-barrier structures, with and without an externally applied electric field. The results indicate that the degree of structural asymmetry and external electric field can greatly affect the dwell times of electrons with opposite spin orientation. This opens up the possibilities of obtaining efficient spin separation in the time domain. The material system of choice is AlxGa1-xSb, and the presented model takes into account the position dependence of material parameters, as well as the effects of band nonparabolicity. (C) 2008 American Institute of Physics.
T2  - Journal of Applied Physics
T1  - Spin-dependent dwell times of electron tunneling through double- and triple-barrier structures
VL  - 103
IS  - 8
DO  - 10.1063/1.2904869
ER  - 

@article{
author = "Erich, Marko and Radovanović, Jelena V. and Milanović, Vitomir B. and Ikonić, Zoran and Indjin, Dragan",
year = "2008",
abstract = "We have analyzed the influence of Dresselhaus and Rashba spin-orbit couplings (caused by the bulk inversion asymmetry and the structural asymmetry, respectively) on electron tunneling through a double- and triple-barrier structures, with and without an externally applied electric field. The results indicate that the degree of structural asymmetry and external electric field can greatly affect the dwell times of electrons with opposite spin orientation. This opens up the possibilities of obtaining efficient spin separation in the time domain. The material system of choice is AlxGa1-xSb, and the presented model takes into account the position dependence of material parameters, as well as the effects of band nonparabolicity. (C) 2008 American Institute of Physics.",
journal = "Journal of Applied Physics",
title = "Spin-dependent dwell times of electron tunneling through double- and triple-barrier structures",
volume = "103",
number = "8",
doi = "10.1063/1.2904869"
}

Erich, M., Radovanović, J. V., Milanović, V. B., Ikonić, Z.,& Indjin, D.. (2008). Spin-dependent dwell times of electron tunneling through double- and triple-barrier structures. in Journal of Applied Physics, 103(8).
https://doi.org/10.1063/1.2904869

Erich M, Radovanović JV, Milanović VB, Ikonić Z, Indjin D. Spin-dependent dwell times of electron tunneling through double- and triple-barrier structures. in Journal of Applied Physics. 2008;103(8).
doi:10.1063/1.2904869 .

Erich, Marko, Radovanović, Jelena V., Milanović, Vitomir B., Ikonić, Zoran, Indjin, Dragan, "Spin-dependent dwell times of electron tunneling through double- and triple-barrier structures" in Journal of Applied Physics, 103, no. 8 (2008),
https://doi.org/10.1063/1.2904869 . .