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The Laboratory for Fundamental and Applied Nanoscale Physics(LAFANP) uses innovative experimental techniques to examine the physical properties of Excitonic Aharonov Bohm Effect in stacked ZnTe/ ZnSe submonolayer Quantum Dots.
Type-II heterostructures have several substantial advantages over type-I systems in that that they suppress non-radiative Auger recombination (1, 2) and their emission can be controlled by external means such as intensity of excitation, electric and magnetic fields. We particularly focused on properties of epitaxial ZnTe/ZnSe quantum dot multilayers, type-II colloidal core-shell nanoparticles, and II-VI nanowires.
In the ZnTe-ZnSe systems holes are strongly confined within ZnTe-rich quantum dots, whereas electrons locate in ZnSe barriers, and only weakly attracted to holes via the Coulomb interaction, forming the spatially indirect (type-II) excitons. It is important that QDs in this system coexist with Ten isoelectronic centers, and a smooth transition between these two different species is indicated by experimental results.
1. H. Ji, B. Roy, S. Dhomkar, R. Moug, M.C. Tamargo, A. Wang, and Igor L. Kuskovsky, Tuning between Quantum-Dot and Quantum-Well-Like Behaviors in Type-II ZnTe Sb-Monolayer Quantum Dots by Controlling Tellurium Flux during MBE growth, J. Electron. Mater. (under review).
2. S. Dhomkar, U. Manna, M.C. Tamargo, I.C. Noyan, and Igor L. Kuskovsky, Optimization of growth conditions of type-II Zn(Cd)Te/ZnCdSe submonolayer quantum dot superlattices for intermediate band solar cells, J. Vac. Sci. Technol. B 31, 03C119 (2013).
3. B. Roy, H. Ji, S. Dhomkar, F.J. Cadieu, L. Peng, R. Moug, M.C. Tamargo, and Igor L. Kuskovsky, Distinguishability of stacks in ZnTe/ZnSe quantum dots via spectral analysis of Aharonov-Bohm oscillations, Eur. Phys. J. B 86, 31 (2013).
4. B. Roy, H. Ji, S. Dhomkar, F.J. Cadieu, L. Peng, R. Moug, M.C. Tamargo, Y. Kim, D. Smirnov, and Igor L. Kuskovsky, Enhancement and narrowing of the Aharonov-Bohm oscillations due to built-in electric field in stacked type-II ZnTe / ZnSe quantum dots : Spectral analysis, Phys. Rev. B 86, 165310 (2012).
5. B. Roy, H. Ji, S. Dhomkar, F.J. Cadieu, L. Peng, R. Moug, M.C. Tamargo, and Igor L. Kuskovsky, Determination of excitonic size with sub-nanometer precision via excitonic Aharonov-Bohm effect in type-II quantum dots, Appl. Phys. Lett. 100, 213114 (2012).
6. U. Manna, Q. Zhang, S. Dhomkar, I.F. Salakhutdinov, M.C. Tamargo, I.C. Noyan, G.F. Neumark, and Igor L. Kuskovsky, Radiative transitions in stacked type-II ZnMgTe quantum dots embedded in ZnSe, J. Appl. Phys. 112, 063521 (2012).
7. U. Manna, I.C. Noyan, Q. Zhang, I.F. Salakhutdinov, K.A. Dunn, S.W. Novak, R. Moug, M.C. Tamargo, G.F. Neumark, and Igor L. Kuskovsky, Structural properties and spatial ordering in multilayered ZnMgTe/ZnSe type-II quantum dot structures, J. Appl. Phys. 111, 033516 (2012).
8. B. Roy, A. Shen, M.C. Tamargo, and Igor L. Kuskovsky, Effects of Varying MBE Growth Conditions on Layered Zn-Se-Te Structures, J. Electron. Mater. 40, 1775–1780 (2011).
9. Q. Zhang, A. Shen, Igor L. Kuskovsky, and M.C. Tamargo, Role of magnesium in band gap engineering of sub-monolayer type-II ZnTe quantum dots embedded in ZnSe , J. Appl. Phys. 110, 034302 (2011).
10. Igor L. Kuskovsky, Y. Gong, G.F. Neumark, and M.C. Tamargo, Photoluminescence and magneto-optical properties of multilayered type-II ZnTe/ZnSe quantum dots, Superlattices Microstruct. 47, 87–92 (2010).
11. V.A. Shuvayev, Igor L. Kuskovsky, L.I. Deych, Y. Gu, Y. Gong, G.F. Neumark, M.C. Tamargo, and A.A. Lisyansky, Dynamics of the radiative recombination in cylindrical nanostructures with type-II band alignment, Phys. Rev. B 79, 115307 (2009).
12. F. Xu, V. Volkov, Y. Zhu, H. Bai, A. Rea, N. V. Valappil, W. Su, X. Gao, I.L. Kuskovsky, and H. Matsui, Long Electron−Hole Separation of ZnO-CdS Core−Shell Quantum Dots, J. Phys. Chem. C 113, 19419–19423 (2009).
1. I. R. Sellers, V. R. Whiteside, Igor L. Kuskovsky, A. O. Govorov, B. D. McCombe, Aharanov-Bohm excitons at elevated temperatures in type-II ZnTe/ZnSe quantum dots, Phys. Rev. Lett. 100, 136405 (2008).
2. M. C-K. Cheung, A. N. Cartwright, I. R. Sellers, B. D. McCombe, and Igor L. Kuskovsky, Time-resolved photoluminescence of type-II quantum dots and isoelectronic centers in Zn-Se-Te superlattice structures, Appl. Phys. Lett. 92, 032106 (2008).
3. I.R. Sellers, V.R. Whiteside, I.L. Kuskovsky, A.O. Govorov, and B.D. McCombe, Modulation of the Aharonov–Bohm effect in type-II II–V ZnSe:Te quantum dots by a far-infrared laser, Physica E 40, 1819 (2008).
4. M.C.-K. Cheung, I.R. Sellers, I.L. Kuskovsky, A.N. Cartwright, and B.D. McCombe, Ultrafast time-resolved photoluminescence of Zn-Se-Te multilayers with type-II ZnTe/ZnSe quantum dots, Proceedings of SPIE 6892, 68921A (2008).
5. L.G. Mourokh, Igor. L. Kuskovsky, A.Yu. Smirnov, H. Matsui, Förster transfer in coupled colloidal type-II and type-I quantum dots, Proceedings of NSTI-Nanotech 2008, www.nsti.org, ISBN 978-1-4200-8503-7, 1 (2008).
6. Y. Gong, W. MacDonald, G. F. Neumark, M. C. Tamargo, and Igor L. Kuskovsky, Optical Properties and Growth Mechanism of Multiple Type-II ZnTe/ZnSe Quantum Dots Grown by Migration Enhanced Epitaxy, Phys. Rev. B. 77, 155314 (2008).
7. Igor L. Kuskovsky, W. MacDonald, A. O. Govorov, L. Muroukh, X., Wei, M. C. Tamargo, M. Tadic, and F. M. Peeters, Optical Aharonov-Bohm effect in stacked type-II quantum dots, Phys. Rev. B 76, 035342 (2007).
8. Y. Gong, T. Andelman, G. F. Neumark, S. O'Brien, and Igor L. Kuskovsky, Origin of defect-related green emission from ZnO nanoparticles: effect of surface modification, Nanoscale Res. Lett. 2, 297 (2007).
9. Igor L. Kuskovsky, Y. Gu, Y. Gong, H. F. Yan, J. Lau, I. C. Noyan, G. F. Neumark, O. Maksimov, X. Zhou, M. C. Tamargo, V. Volkov, Y. Zhu, and L. Wang, Mechanism for increasing dopant incorporation in semiconductors via doped nanostructures, Phys. Rev. B 73, 195306 (2006).
10. Y. Gong, Hanfei F. Yan, I. L. Kuskovsky, Y. Gu, I. C. Noyan, and G. F. Neumark, and M. C. Tamargo, Structure of Zn–Se–Te system with submonolayer insertion of ZnTe grown by migration enhanced epitaxy, J. Appl. Phys. 99, 064913 (2006).
11. O. Maksimov, Y. Gong, H. Duc, P. Fisher, M. Skowronski, Igor L. Kuskovsky, and V.D. Heydemann, Structural and optical properties of GaN films grown on GaAs substrates by molecular beam epitaxy, Vacuum 80, 1042 (2006).
12. T. Andelman, Y. Gong, M. Polking, M. Yin, Igor L. Kuskovsky, G. Neumark, and S. O'Brien, Morphological Control and Photoluminescence of Zinc Oxide Nanocrystals, J. Phys. Chem. B 109, 14314 (2005).
13. Y. Gu, Igor L. Kuskovsky, M. van der Voort, G.F. Neumark, X. Zhou, and M.C. Tamargo, Zn-Se-Te Multilayers With Sub-monolayer Quantities of Te: Type-II Quantum Structures and Isoelectronic Centers , Phys. Rev. B 70, 045340 (2005).
14. Y. Gu, Igor L. Kuskovsky, R. D. Robinson, I. P. Herman, G. F. Neumark, X. Zhou, S. P. Guo, M. Munoz, and M. C. Tamargo, A comparison between optically active CdZnSe/ZnSe and CdZnSe/ZnBeSe self-assembled quantum dots: effect of beryllium, Solid Sate Commun. 134, 677 (2005).
1. Y. Gu, Igor L. Kuskovsky, Y. Min, S. O'Brien, G. F. Neumark, Quantum Confinement in ZnO Nanorods, Appl. Phys. Lett. 85, 3383 (2004).
2. Ming Yin, Yi Gu, Igor L. Kuskovsky, Tamar Andelman, Yimei Zhu, G.F. Neumark, and Stephen O'Brien , Zinc Oxide Quantum Rods, J. Am. Chem Soc. (Communications) 126, 6206 (2004).
3. Igor L. Kuskovsky, Y. Gu, M. van der Voort, G. F. Neumark, X. Zhou, M. Munoz, and M.C. Tamargo, Quantum structures in Zn-Se-Te system containing submonolayer quantities of Te, Phys. Stat. Sol. (b) 241, 527 (2004).
4. Igor L. Kuskovsky, Y. Gu, G.F. Neumark, S.P. Guo, and M.C. Tamargo, Optical properties of semiconductors with the Coulomb potential fluctuation: case of co-doped ZnSe:(N,Cl), Phys. Stat. Sol. (c) 1, 686 (2004).
5. Y. Gu, Igor L Kuskovsky, J. Fung, G.F. Neumark, X. Zhou, S.P. Guo, and M.C. Tamargo, Optical investigation of CdSe/Zn(Be)Se quantum dot structures: size and Cd composition, Phys. Stat. Sol. (c) 1, 779 (2004).
6. Y. Gu, Igor L. Kuskovsky, M. van der Voort, G. F. Neumark, X. Zhou, M. Munoz, and M. C. Tamargo, Time resolved photoluminescence studies of Zn-Se-Te nano- structures with sub-monolayer quantities of Te grown by molecular beam epitaxy, Phys. Stat. Sol. (b) 241, 550 (2004).
7. V.N. Bondarev, Igor L Kuskovsky, Y. Gu, P.V. Pikhitsa, V. M. Belous, G.F. Neumark, S.P. Guo, and M.C. Tarmargo, "Fluctuation Theory of Donor-Acceptor Pair Luminescence in Heavily-doped Semiconductors", Phys. Stat. Sol. (c) 1, 722 (2004).
8. Y. Gu, Igor L. Kuskovsky, J. Fung, R. Robinson, I.P. Herman, G.F. Neumark, X. Zhou, S.P. Guo and M.C. Tamargo, Determination of Size and Composition of Optically Active CdZnSe/ZnBeSe Quantum Dots, Appl. Phys. Lett. 83, 3779 (2003).
9. X. Zhou, Y. Gu, Igor L. Kuskovsky, L. Zeng, G.F. Neumark, and M.C. Tamargo, Photoluminescence of ZnxCdyMg1-x-ySe alloys as a manifestation of the breakdown of "common-anion rule", J. Appl. Phys. 94, 7136 (2003).
10. Y. Gu, Igor L. Kuskovsky, G.F. Neumark, X. C. Zhou, O. Maksimov, S.P. Guo, and M. C. Tamargo, Observation of Free-to-Acceptor-Type Photoluminescence in Chlorine-doped Zn(Be)Se, J. Lum. 108, 77 (2003).
11. Y. Gu, Igor L. Kuskovsky, G.F. Neumark, W. Lin, S.P. Guo, O. Maksimov, and M.C. Tamargo, Heavily p-type doped ZnSe using Te and N co-doping, J. Elect. Materials 31, 799 (2002).
12. Igor L. Kuskovsky, Y. Gu, M. van der Voort, C. Tian, B. Kim, I.P. Herman, G.F. Neumark, S. P. Guo, O. Maksimov, and M.C. Tamargo, Properties of MBE-Grown ZnBeSe: Study of Be Isoelectronic Traps and of Dopant Behavior, Phis. Stat. Sol. (b) 229, 239 (2002).
13. Igor L. Kuskovsky, M. van der Voort, C. Tian, G.F. Neumark, W.-C. Lin, S. P. Guo, M.C. Tamargo, A.N. Alyoshin, and V.M. Belous, Heavily p-type doped ZnSe and ZnBeSe, Phis. Stat. Sol. (b) 229, 385 (2002).
14. Igor L. Kuskovsky, C. Tian, C. Sudbrack, G.F. Neumark, W.-C. Lin, S. P. Guo, and M.C. Tamargo, Photoluminescence of ä-doped ZnSe:(Te,N) Grown by Molecular Beam Epitaxy, J. Appl. Phys. 90, 2269 (2001).
15. S. P. Guo, X. Zhou, O. Maksimov, M. C. Tamargo, C. Chi, A. Couzis, and C. Maldarelli, Igor L. Kuskovsky, and G. F. Neumark, Effects of Be on the II-VI/GaAs interface and on CdSe Quantum Dot Formation, J. Vac. Sci. Tech. B 19, 1635 (2001).
16. Bosang Kim, Igor L. Kuskovsky, C. Tian, Irving P. Herman, G. F. Neumark, S.P. Guo, and M.C. Tamargo, Evidence of Isoelectronic Traps in MBE Grown Zn1-xBexSe: Temperature and Pressure Dependent Photoluminescence Studies, Appl. Phys. Lett. 78, 4151 (2001).
17. S. P. Guo, W. Lin, X. Zhou, M. C. Tamargo, C. Tian, Igor L. Kuskovsky, and G. F. Neumark, High quality and high p-type doping of ZnBeSe using modified (N+Te) ä-doping techniques, J. Appl. Phys. 90, 1725 (2001).
18. Igor L. Kuskovsky, C. Tian, G.F. Neumark, J.E. Spanier, and I.P. Herman, S.P. Guo, and M.C. Tamargo, Optical Properties of ä-doped ZnSe:Te Grown by Molecular Beam Epitaxy: The Role of Tellurium, Phys. Rev. B 63, 155205 (2001).
19. Igor L. Kuskovsky, G. F. Neumark, J.G. Tischler, and B. A. Weinstein, Resonant donor defect as a cause of compensation in p-type ZnSe: Photoluminescence studies under hydrostatic pressure, Phys. Rev. B 63, 161201 (2001).
1. I. Kuskovsky, C. Tian, C. Sudbrack, G.F. Neumark, S.P. Guo, and M.C. Tamargo, Photoluminescence Characterization of MBE Grown ZnBeSe, J. Crystal Growth 214/215, 1058 (2000).
2. W. Lin, S.P. Guo, M.C. Tamargo, I. Kuskovsky, C. Tian, and G.F. Neumark, Enhancement of p-type Doping of ZnSe Using a Modified (N+Te) ä-doping Technique, Appl. Phys. Lett. 76, 2205 (2000).
3. S.P. Guo, Y. Luo, W. Lin, O. Maksimov, M.C. Tamargo, I. Kuskovsky, C. Tian, and G. F. Neumark, High Crystalline Quality ZnBeSe Grown By Molecular Beam Epitaxy With Be-Zn Co-Irradiation, J. Crystal Growth 208, 205 (2000).
4. I. Kuskovsky, B.S. Lim, and A.S. Nowick, Low-temperature Dielectric Relaxation Peaks Involving Proton Tunneling in Ba1-xNdxCeO3, Phys. Rev. B 60, R3713 (1999).
5. I. Kuskovsky, D. Li, G.F. Neumark, V.N. Bondarev, and P.V. Pikhitsa, The Role of Potential Fluctuations in cw Luminescence of Heavily Doped Materials, Appl. Phys. Lett. 75, 1243 (1999).
6. Bosang Kim, I. Kuskovsky, Irving P. Herman, D. Li, and G.F. Neumark, Reversible Ultraviolet-induced Photoluminescence Degradation and Enhancement in GaN Films, J. Appl. Phys. 86, 2034 (1999).
7. I. Kuskovsky, G.F. Neumark, V.N. Bondarev, and P.V. Pikhitsa, Study of Luminescence in Semiconductors in the Presence of Fluctuations, Proceedings of ICPS 24, Jerusalem, Israel ed. D. Gershon, World Scientific, Singapore, 1999.
8. A.S. Nowick, A.V. Vaysleyb, and I. Kuskovsky, Universal Dielectric Response (UDR) of Variously Doped CeO2 Ionically Conducting Ceramics, Phys. Rev. B 58, 8398 (1998).
9. I. Kuskovsky, G.F. Neumark, V.N. Bondarev, and P.V. Pikhitsa, Decay Dynamics In Disordered Systems: Application To Heavily Doped Semiconductors, Phys. Rev. Lett. 80, 2413 (1998).
10. I. Kuskovsky, D. Li, G.F. Neumark, M. Moldovan, N. Giles, V.N. Bondarev, and P.V. Pikhitsa, Time-Resolved Photoluminescence of Nitrogen Doped ZnSe: Role of Fluctuations, J. Crystal Growth 184/185, 525 (1998).
11. C. Kothandaraman, I. Kuskovsky, G.F. Neumark, and R.M. Park, Time-Resolved Luminescence Studies Of Heavily Nitrogen Doped ZnSe, Appl. Phys. Lett. 69, 1523 (1996).
12. I. Kuskovsky and G.F. Neumark, Doping And Non-Equilibrium During Low-Temperature Growth (Application To MBE), Inst. Phys. Conf. Ser. 155, 227 (1996).
13. I. Kuskovsky and G. F. Neumark, Characterization of ZnSe:N using screening effects, Proc. MRS 406, 443 (1996).
14. V. N. Bondarev and I. Kuskovsky, Dynamics of Fluctuations and 'Universal' Electrical Response in Conducting Systems, Sov. Electrochem. 28, 1254, (1992).
15. V. N. Bondarev and I. Kuskovski, On the Theory of Roton-Limited Mobility of Charges in HeII, Sov. Journal of Low Temp. Phys. 18, 217 (1992).
65-30 Kissena Blvd.
Flushing, NY 11367
Phone: (718) 997-3350
Fax: (718) 997-3349
| Dr. Igor L. Kuskovsky |
SB B206 (718) 997-3367 |
| Siddharth Dhomkar |
SB B209 (718) 997-3370 |
| Haojie Ji |
SB B209 (718) 997-3370 |
| Bidisha Roy |
SB B207 (718) 997-3368 |