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Spherical and cylindrical nanolayers: electronic states, quantum transitions Hayk Sarkisyan Russian-Armenian (Slavonic) University Yerevan State University
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The idea of size-quantisation
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Some geometries of quantum dots
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Fulerens and nanotubes
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Simple models of layered systems
Z O R1 R2 X Y Z O Spherical layer QD Cylindrical layer QD
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GaInAs quantum rings Lorke et al (Phys. Rev. Lett. 84, 2223 (2000)).
Fig. 1. GaInAs quantum rings Lorke et al (Phys. Rev. Lett. 84, 2223 (2000)). 250250 нм2.
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Bound structures of quantum layer
Fig. 2. Bound structures of quantum layer
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Chakraborty-Pietilainen model (Phys. Rev. Lett. 84, 2223 (2000))
Fig. 3. Chakraborty-Pietilainen model (Phys. Rev. Lett. 84, 2223 (2000)) Fig. 4. Smorodinsky-Winternitz model (Yadernaya fizika 4, 625 (1966)).
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Difference between potentials profiles:
2 1 Fig. 5. Difference between potentials profiles: 1. Chakraborty-Pietilainen model, 2. Smorodinsky-Winternitz model
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1. Parameters of quantum ring
Experimental data (Lorke et al - Phys. Rev. Lett. 84, 2223 (2000)) quantum ring – InAs coating – GaAs inner radius – 10 nm outer radius – from 30 to 70 nm thickness – 2 nm L R1 R2 z o Cylindrical layer quantum dot
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2. Models of confining potentials
1. – Chakraborty-Pietilainen model (Phys. Rev. B 50, 8460 (1994)). 2. – Model of the impenetrable cylindrical layer quantum dot (Physica E 36, 114 (2007) ) 3. – Smorodinsky-Winternitz model (Yadernaya fizika 4, 625 (1966)). 4. – Radial analog of the Smorodinsky-Winternitz potential
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3. Quantum ring in the magnetic field
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F(a,b,x) – confluent hypergeometrical function.
– effective mass of the electron ( – hole ) F(a,b,x) – confluent hypergeometrical function.
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4. Absorption coefficient
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5. Influence of electric field
z o
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6. Rotator model L R1 R2 z o x
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Rotational levels Radial level
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7. Electronic states in the spherical nanolayer 1. E.M. Kazaryan, A.A. Kostanyan, H.A. Sarkisyan, J. Cont. Phys. (2007). 2. M.A. Zuhair, A.Kh. Manaselyan, H.A. Sarkisyan, J. Phys.: Conf. Ser. (2008).
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Parabolic quantum well with hydrogen-like impurity
1A. A. Gusev, et al, Phys. At. Nucl., 2010, Vol. 73, (accepted).
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THANK YOU!
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