Slow and Fast Light Propagation in Semiconductor Quantum Dots

The transmission and reflection properties of a pulse through a slab doped with quantum dots near a plasmonic nanostructure are investigated theoretically. It is found that by adjusting the distance between plasmonic nanostructure and dual quantum dots which is varied from 8.8 nanometer (nm) to 14.4 nanometer (nm) the transmission and reflection spectra for incident pulse through the slab can be modified. Furthermore, it is found that in the presence of plasmonic nanostructure, the reflected and transmitted pulses are completely phase dependent. Therefore, the group velocity of the reflected and transmitted pulses can be switched from slow to fast light by changing the phase difference of two laser fields.

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Tunable phase control of slow and fast light propagation in a slab doped by four-level quantum dot nanostructure

Modern Physics Letters B ◽

10.1142/s0217984915502310 ◽

2015 ◽

Vol 29 (35n36) ◽

pp. 1550231 ◽

Cited By ~ 2

Author(s):

Hossein Jafarzadeh ◽

Elnaz Ahmadi Sangachin ◽

Seyyed Hossein Asadpour

Keyword(s):

Quantum Dot ◽

Group Velocity ◽

Light Propagation ◽

Phase Variation ◽

Phase Control ◽

Dielectric Slab ◽

Fast Light ◽

Slow And Fast Light ◽

Signal Field

Tunable phase control of the slow and fast light propagation through a defect slab medium doped by four-level InGaN/GaN quantum dot structure is demonstrated. By solving the Schrödinger and Poisson’s equations self-consistently, a spherical InGaN quantum dot with GaN barrier shell which can interact by terahertz (THz) signal field is designed numerically. It is found that the phase variation of THz signal field imparts the tunability in the group velocity of the transmitted and reflected pulses through a dielectric slab.

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Infrared control of slow light in a slab doped by InGaN/GaN quantum dot nanostructure

Modern Physics Letters B ◽

10.1142/s0217984915500128 ◽

2015 ◽

Vol 29 (05) ◽

pp. 1550012

Author(s):

Hossein Jafarzadeh ◽

Elnaz Ahmadi Sangachin ◽

Seyyed Hossein Asadpour

Keyword(s):

Quantum Dot ◽

Communication Systems ◽

Light Propagation ◽

Slow Light ◽

Optical Systems ◽

Proposed Model ◽

Ultrahigh Density ◽

Fast Light ◽

Slow And Fast Light ◽

Signal Field

In this paper, we proposed a model for controlling the group velocity of the transmitted and reflected pulses in a slab medium doped by four-level quantum dot nanostructure. Here, an infrared signal field interacted by quantum dot nanostructure can affect the behavior of reflected and transmitted pulses. We show that in the presence and absence of infrared pulses, the other controllable parameters have essential roles for controlling the slow and fast light propagation through the medium. Moreover, we found that the simultaneous slow and fast light can be obtained for the transmitted and reflected pulses by infrared signal field. Our proposed model may be useful for ultrahigh density optical memories in quantum communication systems or in various fields of all-optical systems.

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