Finite parabolic quantum wells under crossed electric and magnetic fields: a double-quantum-well problem

1998 ◽  
Vol 10 (43) ◽  
pp. 9755-9762 ◽  
Author(s):  
L G Guimarães ◽  
Rosana B Santiago
1994 ◽  
Vol 358 ◽  
Author(s):  
Tiesheng Li ◽  
H. J. Lozykowski

ABSTRACTExperimental and theoretical investigations of electronic states in a strained-layer CdTe/CdZnTe coupled double quantum well structure are presented. The optical properties of this lattice mismatched heterostructure were characterized by photoluminescence (PL), PL excitation and polarization spectroscopies. The influence of electrical field on exciton states in the strained layer CdTe/CdZnTe coupled double quantum well structure is experimentally studied. The confined electronic states were calculated in the framework of the envelope function approach, taking into account the strain effect induced by the lattice-mismatch. Experimental results are compared with the calculated transition energies.


1994 ◽  
Vol 08 (18) ◽  
pp. 1075-1096 ◽  
Author(s):  
W. E. MCMAHON ◽  
T. MILLER ◽  
T.-C. CHIANG

Noble-metal multilayer systems have been grown and examined with angle-resolved photoemission. Surface states, and single and double quantum wells have been studied experimentally; the results can be explained with a simple theoretical model based upon Bloch electrons. In this paper, we will present our model and then give a description of some experimental studies which utilize the model. In particular, we will consider double-quantum-well systems which can be used to examine basic aspects of electronic confinement, layer–layer coupling, and translayer interaction through a barrier.


NANO ◽  
2009 ◽  
Vol 04 (05) ◽  
pp. 289-297
Author(s):  
MONICA GAMBHIR ◽  
SIDDHARTHA LAHON ◽  
PRADEEP KUMAR JHA ◽  
MAN MOHAN

The basic technique of stimulated Raman adiabatic passage for laser-induced adiabatic population transfer between discrete quantum states of an asymmetric double quantum well has been used in our study. The results show that the proper time-delay, overlap, and detuning of two pulses allows the coherent transfer between the states of a double quantum well system, leading to the possibility of implementation of semiconductor–based quantum logic gates and high efficiency optical switches. The impact of phase relaxation on the population transfer efficiency is also studied.


1987 ◽  
Vol 102 ◽  
Author(s):  
Y. J. Chen ◽  
Emil S. Koteles ◽  
B. Elman ◽  
C. A. Armiento

ABSTRACTWe present a detailed experimental study of the influence of electric fields on exciton states in a GaAs/AlGaAs coupled double quantum well structure and discuss the advantages of using this novel structure. The coupling of electronic states in the two quantum wells, due to the narrowness of the barrier between them, leads to an enhancement of the quantum-confined Stark effect (by as much as five times that of the single quantum well case). From the measured energies of the exciton transitions, splittings of the levels in a coupled double quantum well structure were derived without recourse to a theoretical model.


2020 ◽  
Vol 54 (7) ◽  
pp. 676
Author(s):  
S.R. Panda ◽  
A. Sahu ◽  
S. Das ◽  
A.K. Panda ◽  
T. Sahu

We analyze the asymmetric delta-doping dependence of nonlinear electron mobility μ of GaAs|InxGa1-xAs double quantum-well pseudo-morphic modulation doped field-effect transistor structure. We solve the Schrodinger and Poisson's equations self-consistently to obtain the sub-band energy levels and wave functions. We consider scatterings due to the ionized impurities (IMP), alloy disorder (AL), and interface roughness (IR) to calculate μ for a system having double sub-band occupancy, in which the inter-sub-band effects play an important role. Considering the doping concentrations in the barriers towards the substrate and surface sides as Nd1 and Nd2, respectively, we show that variation of Nd1 leads to a dip in μ near Nd1=Nd2, at which the resonance of the sub-band states occurs. A similar dip in μ as a function of Nd1 is also obtained at Nd1=Nd2 by keeping (Nd1+Nd2) unchanged. By increasing the central barrier width and well width, the dip in μ becomes sharp. We note that even though the overall μ is governed by the IMP- and AL-scatterings, the dip in μ is mostly affected through substantial variation of the sub-band mobilities due to IR-scattering near the resonance. Our results of nonlinear electron mobility near the resonance of sub-band states can be utilized for the performance analysis of GaAs|InGaAs pseudo-morphic quantum-well field-effect transistors. Keywords: asymmetric double quantum wells, GaAs|InxGa1-xAs structures, nonlinear electron mobility, pseudo-morphic HEMT structures, resonance of sub-band states.


2006 ◽  
Vol 34 (1-2) ◽  
pp. 284-287 ◽  
Author(s):  
M. Orlita ◽  
M. Byszewski ◽  
G.H. Döhler ◽  
M. Grill ◽  
P. Hlídek ◽  
...  

1997 ◽  
Vol 484 ◽  
Author(s):  
Jie Dong ◽  
Akinoi Ubukata ◽  
Koh Matsumoto

AbstractIn this study, we demonstrate the growth of highly compressively strained InGaAs/JnGaAsP quantum well structures with large well thiclmess by low pressure metalorganic chemical vapor deposition for extending the emission wavelength of lasers. By comparing the photolumineswnce characteristics of quantum wells grown at different temperatures, it is clarified that a relatively high quality quantum well layer emittig at 2.0 μ, can be obtained at a growth temperature of 650°C. 1.95-μm-wavelength InGaAs/InGaAsP highly compressively strained quantum well DFB laser for laser spectroscopy monitors was also fabricated. Double quantum-well DFB laser operating at 1.95 μm exhibits threshold currents as low as 6 mA and 6.2 mW maximum output powers. 2.04-μm-wavelength DFB laser is also described.


Sign in / Sign up

Export Citation Format

Share Document