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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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Presentation on theme: "Spherical and cylindrical nanolayers: electronic states, quantum transitions Hayk Sarkisyan Russian-Armenian (Slavonic) University Yerevan State University."— Presentation transcript:

1 Spherical and cylindrical nanolayers: electronic states, quantum transitions Hayk Sarkisyan Russian-Armenian (Slavonic) University Yerevan State University

2 The idea of size-quantisation

3 Some geometries of quantum dots

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5 Fulerens and nanotubes

6 Simple models of layered systems
Z O R1 R2 X Y Z O Spherical layer QD Cylindrical layer QD

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8 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)). 250250 нм2.

9 Bound structures of quantum layer
Fig. 2. Bound structures of quantum layer

10 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)).

11 Difference between potentials profiles:
2 1 Fig. 5. Difference between potentials profiles: 1. Chakraborty-Pietilainen model, 2. Smorodinsky-Winternitz model

12 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

13 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

14 3. Quantum ring in the magnetic field

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16 F(a,b,x) – confluent hypergeometrical function.
– effective mass of the electron ( – hole ) F(a,b,x) – confluent hypergeometrical function.

17 4. Absorption coefficient

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19 5. Influence of electric field
z o

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21 6. Rotator model L R1 R2 z o x

22 Rotational levels Radial level

23 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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25 Parabolic quantum well with hydrogen-like impurity
1A. A. Gusev, et al, Phys. At. Nucl., 2010, Vol. 73, (accepted).

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28 THANK YOU!


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