1. |
- Felici, M, et al.
(författare)
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High Energy Optical Transitions in Ga(PN) : Contribution from Perturbed Valence Band
- 2005
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Ingår i: AIP Conference Proceedings / Volume 772. - : American Institute of Physics (AIP). - 0735402574 ; , s. 265-
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Konferensbidrag (refereegranskat)abstract
- The GaP1–xNx conduction band is investigated experimentally (by excitation photoluminescence) andtheoretically (by pseudopotential supercells) for N concentrations up to x=3.5%and photon energies ranging from the optical absorption edge to3.2 eV. With increasing x: (i) a direct-like absorption edgedevelops smoothly and red-shifts rapidly overtaking energy-pinned cluster states; (ii)a broad absorption plateau appears between the X1c and the1c critical points of GaP; (iii) the 1c absorption edgebroadens and gradually disappears. Empirical pseudopotential calculations for GaP1-xNx randomalloy supercells account well for all the PLE results byconsidering N induced changes in the valence band overlooked sofar. ©2005 American Institute of Physics
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2. |
- Gvozdic, Dejan, et al.
(författare)
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Strong enhancement of Rashba effect in strained p-type quantum wells
- 2005
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Ingår i: Physics of Semiconductors, Pts A and B. - MELVILLE : AMER INST PHYSICS. - 0735402574 ; , s. 1423-1424
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Konferensbidrag (refereegranskat)abstract
- One of the most studied spintronic devices is the spin transistor proposed by Datta and Das. The mechanism behind this transistor is the Rashba effect: The inversion asymmetry caused by the gate voltage gives rise to a spin splitting. We show that the relevant spin splitting in k-space is typically two orders of magnitude larger in unstrained p-type quantum wells compared to n-type quantum wells. We also show that further order-of-magnitude improvement can be obtained by utilizing the frequently ignored lattice-mismatch between GaAs and AlGaAs.
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3. |
- Kyrychenko, F.V., et al.
(författare)
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Investigation of a GaMnN/GaN/InGaN structure for spinLED
- 2005
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Ingår i: 27th Int. Conf. on the Physics of Semicond,2004. - : American Institute of Physics (AIP). - 0735402574 ; , s. 1319-1320
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Theoreticaland experimental studies of GaMnN/GaN/InGaN structure for a spin LEDdevice were performed. Strong electron spin relaxation was experimentally observedin a InGaN/GaN quantum well. It is shown that thestrong spin relaxation might result from the built-in piezoelectric fieldin strained wurzite heterostructures. A five level k · pmodel was used for microscopic calculations of the structure inversionasymmetry induced spin-orbit interaction. The magnitude of this interaction isshown to be comparable with that in InGaAs/GaAs quantum structures.©2005 American Institute of Physics
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