The Experts below are selected from a list of 72 Experts worldwide ranked by ideXlab platform
Mikhail Raikh - One of the best experts on this subject based on the ideXlab platform.
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Many-Body Spin Correlations in Nonlinear Optical Spectroscopy
Journal of Superconductivity, 2001Co-Authors: T. V. Shahbazyan, Ilias E. Perakis, Mikhail RaikhAbstract:We study the role of spin correlations in nonlinear absorption due to optical transitions from a Deep Impurity Level to states above a Fermi sea. We demonstrate that the Hubbard repulsion between two electrons occupying the Impurity state leads to a logarithmic divergence of the third-order nonlinear optical susceptibility χ^(3) at the absorption threshold. This divergence is a manifestation of the Kondo physics in the nonlinear optical response of Fermi sea systems. Remarkably, the light-induced Kondo temperature, which governs the shape of the Kondo-absorption spectrum, can be tuned by varying the intensity and frequency of the pump optical field. We also show that, for off-resonant pump excitation, the pump–probe spectrum exhibits a narrow peak below the linear absorption onset.
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Spin correlations in nonlinear optical response: light-induced Kondo effect.
Physical review letters, 2000Co-Authors: T. V. Shahbazyan, Ilias E. Perakis, Mikhail RaikhAbstract:We study the role of spin correlations in nonlinear absorption due to transitions from a Deep Impurity Level to states above a Fermi sea. We demonstrate that the Hubbard repulsion between two electrons at the Impurity leads to a logarithmic divergence in chi(3) at the absorption threshold. This divergence is a manifestation of the Kondo physics in the nonlinear optical response of Fermi sea systems. We also show that, for off-resonant pump excitation, the pump-probe spectrum exhibits a narrow peak below the linear absorption onset. Remarkably, the light-induced Kondo temperature, which governs the shape of the Kondo-absorption spectrum, can be tuned by varying the intensity and frequency of the pump.
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Spin correlations in nonlinear optical spectroscopy of semiconductor quantum wells
Technical Digest. Summaries of papers presented at the Quantum Electronics and Laser Science Conference. Postconference Technical Digest (IEEE Cat. No, 1Co-Authors: T. V. Shahbazyan, Ilias E. Perakis, Mikhail RaikhAbstract:Summary form only given. The role of many-body correlations in the nonlinear optical spectroscopy of semiconductors has been extensively investigated during the last decade. More recently, there has been a growing interest in the coherent charge and spin dynamics of Fermi sea (FS) systems at low temperatures. Here we suggest a novel many-body effect in the nonlinear absorption of a FS system with a Deep Impurity Level which originates from spin correlations between photoexcited carries and the Fermi sea. We note that a number of different intermediate processes contribute to the third order optical susceptibility.
E. P. Skipetrov - One of the best experts on this subject based on the ideXlab platform.
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Vanadium Deep Impurity Level in diluted magnetic semiconductors Pb1-x-ySnxVyTe
Semiconductors, 2012Co-Authors: E. P. Skipetrov, A. N. Golovanov, A. V. Knotko, E.i. Slynko, V. E. SlynkoAbstract:The crystal structure, Sn and V distribution over the length of single-crystal ingots, and galvanomagnetic effects in low magnetic fields (4.2 K ≤ T ≤ 300 K, B ≤ 0.07 T) in Pb1−x−y Sn x V y Te alloys (x = 0.05−0.21, y ≤ 0.015) are studied. It is shown that all the samples are single-phase, while the Sn and V concentrations exponentially increase from the beginning to the end of the ingots. Upon doping with V, a decrease in the concentration of free holes and a metal-insulator transition are found. They are related to the appearance of a Deep Impurity Level of V in the band gap, electron redistribution between the Level and the valence band, and pinning of the Fermi-Level to the Impurity Level. The shift rate of the V Level relative to the conduction band bottom is determined and a diagram of the reconstruction of the electronic structure of the Pb1 − x − y Sn x V y Te alloy upon varying the host composition is suggested.
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Vanadium Deep Impurity Level in diluted magnetic semiconductors Pb_1 − x − y Sn_ x V_ y Te
Semiconductors, 2012Co-Authors: E. P. Skipetrov, A. N. Golovanov, A. V. Knotko, E. I. Slyn’ko, V. E. Slyn’koAbstract:The crystal structure, Sn and V distribution over the length of single-crystal ingots, and galvanomagnetic effects in low magnetic fields (4.2 K ≤ T ≤ 300 K, B ≤ 0.07 T) in Pb_1− x − y Sn_ x V_ y Te alloys ( x = 0.05−0.21, y ≤ 0.015) are studied. It is shown that all the samples are single-phase, while the Sn and V concentrations exponentially increase from the beginning to the end of the ingots. Upon doping with V, a decrease in the concentration of free holes and a metal-insulator transition are found. They are related to the appearance of a Deep Impurity Level of V in the band gap, electron redistribution between the Level and the valence band, and pinning of the Fermi-Level to the Impurity Level. The shift rate of the V Level relative to the conduction band bottom is determined and a diagram of the reconstruction of the electronic structure of the Pb_1 − x − y Sn_ x V_ y Te alloy upon varying the host composition is suggested.
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vanadium induced Deep Impurity Level in pb1 xsnxte
Physica B-condensed Matter, 2009Co-Authors: E. P. Skipetrov, A. N. Golovanov, E.i. Slynko, Elena A. Zvereva, V. E. SlynkoAbstract:The galvanomagnetic properties (T=4.2―300 K, B≤0.08T) of Pb 1―x―y Sn x V y Te alloys (x=0.06-0.26, y=0.002-0.066) have been investigated. Low temperature activation range of the Impurity conductivity on the temperature dependencies of resistivity p and of the Hall coefficient R H in the heavily doped samples has been revealed and attributed to the appearance of vanadium-induced Deep Level in the gap of the alloys. It was found that in insulating phase alloys possess a high photosensitivity to IR excitation at temperatures up to T c ≈ 40 K. In the alloy with x ≈ 0.2 the metal-insulator transition due to the shift of the Fermi Level from the valence band to the gap with the increase of the vanadium and tin content and the pinning of the Fermi Level by vanadium Level were observed. The diagram of electronic structure reconstruction for Pb 1 ―x―y Sn x V y Te alloys was proposed.
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Vanadium-induced Deep Impurity Level in Pb1−xSnxTe
Physica B-condensed Matter, 2009Co-Authors: E. P. Skipetrov, A. N. Golovanov, E.i. Slynko, Elena A. Zvereva, V. E. SlynkoAbstract:The galvanomagnetic properties (T=4.2―300 K, B≤0.08T) of Pb 1―x―y Sn x V y Te alloys (x=0.06-0.26, y=0.002-0.066) have been investigated. Low temperature activation range of the Impurity conductivity on the temperature dependencies of resistivity p and of the Hall coefficient R H in the heavily doped samples has been revealed and attributed to the appearance of vanadium-induced Deep Level in the gap of the alloys. It was found that in insulating phase alloys possess a high photosensitivity to IR excitation at temperatures up to T c ≈ 40 K. In the alloy with x ≈ 0.2 the metal-insulator transition due to the shift of the Fermi Level from the valence band to the gap with the increase of the vanadium and tin content and the pinning of the Fermi Level by vanadium Level were observed. The diagram of electronic structure reconstruction for Pb 1 ―x―y Sn x V y Te alloys was proposed.
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Gallium-induced Deep Level in Pb_1−x Ge_xTe alloys
Semiconductors, 2000Co-Authors: E. P. Skipetrov, V.v. Belousov, L. A. Skipetrova, E. A. Zvereva, E. I. Slyn’koAbstract:Galvanomagnetic properties of gallium-doped Pb_1− x Ge_xTe (0.04≤ x ≤0.08) alloys were studied. It is shown that gallium doping induces a Deep Impurity Level in the alloy band gap; the energy position of this Level depends on the germanium content in the alloy. A model assuming that doping with gallium results in the emergence of two defect Levels in the energy spectrum of the alloys is proposed.
T. V. Shahbazyan - One of the best experts on this subject based on the ideXlab platform.
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Many-Body Spin Correlations in Nonlinear Optical Spectroscopy
Journal of Superconductivity, 2001Co-Authors: T. V. Shahbazyan, Ilias E. Perakis, Mikhail RaikhAbstract:We study the role of spin correlations in nonlinear absorption due to optical transitions from a Deep Impurity Level to states above a Fermi sea. We demonstrate that the Hubbard repulsion between two electrons occupying the Impurity state leads to a logarithmic divergence of the third-order nonlinear optical susceptibility χ^(3) at the absorption threshold. This divergence is a manifestation of the Kondo physics in the nonlinear optical response of Fermi sea systems. Remarkably, the light-induced Kondo temperature, which governs the shape of the Kondo-absorption spectrum, can be tuned by varying the intensity and frequency of the pump optical field. We also show that, for off-resonant pump excitation, the pump–probe spectrum exhibits a narrow peak below the linear absorption onset.
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Spin correlations in nonlinear optical response: light-induced Kondo effect.
Physical review letters, 2000Co-Authors: T. V. Shahbazyan, Ilias E. Perakis, Mikhail RaikhAbstract:We study the role of spin correlations in nonlinear absorption due to transitions from a Deep Impurity Level to states above a Fermi sea. We demonstrate that the Hubbard repulsion between two electrons at the Impurity leads to a logarithmic divergence in chi(3) at the absorption threshold. This divergence is a manifestation of the Kondo physics in the nonlinear optical response of Fermi sea systems. We also show that, for off-resonant pump excitation, the pump-probe spectrum exhibits a narrow peak below the linear absorption onset. Remarkably, the light-induced Kondo temperature, which governs the shape of the Kondo-absorption spectrum, can be tuned by varying the intensity and frequency of the pump.
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Spin correlations in nonlinear optical spectroscopy of semiconductor quantum wells
Technical Digest. Summaries of papers presented at the Quantum Electronics and Laser Science Conference. Postconference Technical Digest (IEEE Cat. No, 1Co-Authors: T. V. Shahbazyan, Ilias E. Perakis, Mikhail RaikhAbstract:Summary form only given. The role of many-body correlations in the nonlinear optical spectroscopy of semiconductors has been extensively investigated during the last decade. More recently, there has been a growing interest in the coherent charge and spin dynamics of Fermi sea (FS) systems at low temperatures. Here we suggest a novel many-body effect in the nonlinear absorption of a FS system with a Deep Impurity Level which originates from spin correlations between photoexcited carries and the Fermi sea. We note that a number of different intermediate processes contribute to the third order optical susceptibility.
E.i. Slynko - One of the best experts on this subject based on the ideXlab platform.
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Vanadium Deep Impurity Level in diluted magnetic semiconductors Pb1-x-ySnxVyTe
Semiconductors, 2012Co-Authors: E. P. Skipetrov, A. N. Golovanov, A. V. Knotko, E.i. Slynko, V. E. SlynkoAbstract:The crystal structure, Sn and V distribution over the length of single-crystal ingots, and galvanomagnetic effects in low magnetic fields (4.2 K ≤ T ≤ 300 K, B ≤ 0.07 T) in Pb1−x−y Sn x V y Te alloys (x = 0.05−0.21, y ≤ 0.015) are studied. It is shown that all the samples are single-phase, while the Sn and V concentrations exponentially increase from the beginning to the end of the ingots. Upon doping with V, a decrease in the concentration of free holes and a metal-insulator transition are found. They are related to the appearance of a Deep Impurity Level of V in the band gap, electron redistribution between the Level and the valence band, and pinning of the Fermi-Level to the Impurity Level. The shift rate of the V Level relative to the conduction band bottom is determined and a diagram of the reconstruction of the electronic structure of the Pb1 − x − y Sn x V y Te alloy upon varying the host composition is suggested.
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vanadium induced Deep Impurity Level in pb1 xsnxte
Physica B-condensed Matter, 2009Co-Authors: E. P. Skipetrov, A. N. Golovanov, E.i. Slynko, Elena A. Zvereva, V. E. SlynkoAbstract:The galvanomagnetic properties (T=4.2―300 K, B≤0.08T) of Pb 1―x―y Sn x V y Te alloys (x=0.06-0.26, y=0.002-0.066) have been investigated. Low temperature activation range of the Impurity conductivity on the temperature dependencies of resistivity p and of the Hall coefficient R H in the heavily doped samples has been revealed and attributed to the appearance of vanadium-induced Deep Level in the gap of the alloys. It was found that in insulating phase alloys possess a high photosensitivity to IR excitation at temperatures up to T c ≈ 40 K. In the alloy with x ≈ 0.2 the metal-insulator transition due to the shift of the Fermi Level from the valence band to the gap with the increase of the vanadium and tin content and the pinning of the Fermi Level by vanadium Level were observed. The diagram of electronic structure reconstruction for Pb 1 ―x―y Sn x V y Te alloys was proposed.
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Vanadium-induced Deep Impurity Level in Pb1−xSnxTe
Physica B-condensed Matter, 2009Co-Authors: E. P. Skipetrov, A. N. Golovanov, E.i. Slynko, Elena A. Zvereva, V. E. SlynkoAbstract:The galvanomagnetic properties (T=4.2―300 K, B≤0.08T) of Pb 1―x―y Sn x V y Te alloys (x=0.06-0.26, y=0.002-0.066) have been investigated. Low temperature activation range of the Impurity conductivity on the temperature dependencies of resistivity p and of the Hall coefficient R H in the heavily doped samples has been revealed and attributed to the appearance of vanadium-induced Deep Level in the gap of the alloys. It was found that in insulating phase alloys possess a high photosensitivity to IR excitation at temperatures up to T c ≈ 40 K. In the alloy with x ≈ 0.2 the metal-insulator transition due to the shift of the Fermi Level from the valence band to the gap with the increase of the vanadium and tin content and the pinning of the Fermi Level by vanadium Level were observed. The diagram of electronic structure reconstruction for Pb 1 ―x―y Sn x V y Te alloys was proposed.
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Ytterbium-induced Jahn-Teller states in Pb1-xGexTe alloys
Journal of Crystal Growth, 2000Co-Authors: E. P. Skipetrov, N.a. Chernova, E.i. SlynkoAbstract:Abstract We investigate galvanomagnetic properties and photoconductivity kinetics of Pb 1− x Ge x Te ( x ⩽0.04) alloys doped with Yb. We have found that the existence of the Deep Impurity Level in the energy spectrum causes high photosensitivity of the alloys at temperatures under 40 K and the effect of persistent photoconductivity at helium temperature. The photoconductivity kinetics shows two types of relaxation processes: a fast one and a long-duration one. The obtained results are explained by the Jahn–Teller nature of the Yb-induced defect states. The parameters of the Jahn–Teller states are estimated.
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Gallium-induced Deep Level in Pb1−xGexTe alloys
Semiconductors, 2000Co-Authors: E. P. Skipetrov, Elena A. Zvereva, V.v. Belousov, L. A. Skipetrova, E.i. SlynkoAbstract:Galvanomagnetic properties of gallium-doped Pb1−xGexTe (0.04≤x≤0.08) alloys were studied. It is shown that gallium doping induces a Deep Impurity Level in the alloy band gap; the energy position of this Level depends on the germanium content in the alloy. A model assuming that doping with gallium results in the emergence of two defect Levels in the energy spectrum of the alloys is proposed.
Ru Huang - One of the best experts on this subject based on the ideXlab platform.
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A Novel Deep-Impurity-Level Assisted Tunneling Technology for Enhanced Interband Tunneling Probability
2016Co-Authors: Run Dong Jia, Qian Qian Huang, Yang Zhao, Jia Xin Wang, Ru HuangAbstract:In this work, a novel Deep-Impurity-Level assisted tunneling technology with enhanced band to band tunneling(BTBT) probability is proposed and experimentally demonstrated. Through implanting Deep Level impurities in the tunnel junction, continuous Deep Level states can be introduced to facilitate the BTBT process for significant BTBT probability boosting.Compared with conventional tunnel diodes, the fabricated Deep-Impurity-Level assisted tunnel diodes exhibit 7.8x and 23 x current enhancement in P~(++)/N~+ and N~(++)/P~+ tunnel diodes respectively, showing its great potential for future current enhancement in tunnel FETs.In this work, a novel Deep-Impurity-Level assisted tunneling technology with enhanced band to band tunneling(BTBT) probability is proposed and experimentally demonstrated. Through implanting Deep Level impurities in the tunnel junction, continuous Deep Level states can be introduced to facilitate the BTBT process for significant BTBT probability boosting.Compared with conventional tunnel diodes, the fabricated Deep-Impurity-Level assisted tunnel diodes exhibit 7.8x and 23 x current enhancement in P~(++)/N~IEEE Beijing Section
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A novel Deep-Impurity-Level assisted tunneling technology for enhanced interband tunneling probability
2016 13th IEEE International Conference on Solid-State and Integrated Circuit Technology (ICSICT), 2016Co-Authors: Run Dong Jia, Qian Qian Huang, Yang Zhao, Jia Xin Wang, Ru HuangAbstract:In this work, a novel Deep-Impurity-Level assisted tunneling technology with enhanced band to band tunneling (BTBT) probability is proposed and experimentally demonstrated. Through implanting Deep Level impurities in the tunnel junction, continuous Deep Level states can be introduced to facilitate the BTBT process for significant BTBT probability boosting. Compared with conventional tunnel diodes, the fabricated Deep-Impurity-Level assisted tunnel diodes exhibit 7.8× and 23× current enhancement in P++/N+ and N++/P+ tunnel diodes respectively, showing its great potential for future current enhancement in tunnel FETs.
